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Comparison of Wind-Driven Rain Test Methods for Residential Fenestration

Permanent Link: http://ufdc.ufl.edu/UFE0025078/00001

Material Information

Title: Comparison of Wind-Driven Rain Test Methods for Residential Fenestration
Physical Description: 1 online resource (124 p.)
Language: english
Creator: Lopez, Carlos
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2009

Subjects

Subjects / Keywords: fenestration, hurricane, rain, residential, wind
Civil and Coastal Engineering -- Dissertations, Academic -- UF
Genre: Civil Engineering thesis, M.E.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: While recent changes in building codes have resulted in better structural performance during tropical cyclones, water intrusion through the building envelope continues to be a recurring issue. As a result, industry and code officials have voiced a need to reevaluate the standardized test methods in place for product approval. Under the oversight of a task force that includes representatives from product manufacturing, homebuilding, architecture, engineering, insurance, code development and test laboratories, these methods have been investigated through a series of tests that examines full scale wall/window specimens subjected to simulated wind driven rain scenarios. These WDR events were simulated using a pressure chamber, in which full-scale residential wall systems were subjected to uniform, linearly varying, and cyclic pressure loads while the fac cedillaade was wetted. The specimens were also subjected to dynamic loads using a new turbulent wind load simulation apparatus developed at the University of Florida (UF). It was discovered that the static and cyclic pressure testing procedures used in the experiment described herein replicated the results observed in the dynamic pressure test reasonably well. Holistic testing of the specimens also yielded results that demonstrate the importance of testing products as an assembly rather than in isolation.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Carlos Lopez.
Thesis: Thesis (M.E.)--University of Florida, 2009.
Local: Adviser: Masters, Forrest.
Local: Co-adviser: Gurley, Kurtis R.

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2009
System ID: UFE0025078:00001

Permanent Link: http://ufdc.ufl.edu/UFE0025078/00001

Material Information

Title: Comparison of Wind-Driven Rain Test Methods for Residential Fenestration
Physical Description: 1 online resource (124 p.)
Language: english
Creator: Lopez, Carlos
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2009

Subjects

Subjects / Keywords: fenestration, hurricane, rain, residential, wind
Civil and Coastal Engineering -- Dissertations, Academic -- UF
Genre: Civil Engineering thesis, M.E.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: While recent changes in building codes have resulted in better structural performance during tropical cyclones, water intrusion through the building envelope continues to be a recurring issue. As a result, industry and code officials have voiced a need to reevaluate the standardized test methods in place for product approval. Under the oversight of a task force that includes representatives from product manufacturing, homebuilding, architecture, engineering, insurance, code development and test laboratories, these methods have been investigated through a series of tests that examines full scale wall/window specimens subjected to simulated wind driven rain scenarios. These WDR events were simulated using a pressure chamber, in which full-scale residential wall systems were subjected to uniform, linearly varying, and cyclic pressure loads while the fac cedillaade was wetted. The specimens were also subjected to dynamic loads using a new turbulent wind load simulation apparatus developed at the University of Florida (UF). It was discovered that the static and cyclic pressure testing procedures used in the experiment described herein replicated the results observed in the dynamic pressure test reasonably well. Holistic testing of the specimens also yielded results that demonstrate the importance of testing products as an assembly rather than in isolation.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Carlos Lopez.
Thesis: Thesis (M.E.)--University of Florida, 2009.
Local: Adviser: Masters, Forrest.
Local: Co-adviser: Gurley, Kurtis R.

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2009
System ID: UFE0025078:00001


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1 COMPARISON OF WIND-DRIVEN RAIN TEST METHODS FOR RESIDENTIAL FENESTRATION By CARLOS R. LOPEZ A THESIS PRESENTED TO THE GRADUATE SCHOOL OF CIVIL ENGINEERING AT THE UNI VERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIR EMENTS FOR THE DEGREE OF MASTER OF ENGINEERING UNIVERSITY OF FLORIDA 2009

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2 2009 Carlos R. Lopez

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3 To my parents, Amanda Duarte and Alfonso Lopez

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4 ACKNOWLEDGMENTS Without the help of the oversight committee th is research project would not have been possible. I would like to tha nk: Alside, American Architectur al Manufacturers Association (AAMA), American Forest & Paper Associ ation (AFPA), APAThe Engineered Wood Association, Architectural Test ing Inc., Atrium Companies Inc ., Cast-Crete Corporation, C.B. Goldsmith and Associates Inc., CEMEX, Certif ied Test Labs, Do Kim & Associates, DuPont, Fenestration Manufacturers Asso ciation (FMA), Florida Build ing Commission, Florida Home Builders Association (FHBA), General Aluminum Henkel, Institute for Business and Home Safety (IBHS), James Hardie, JBD Code Se rvices, JELD-WEN Windows and Doors, Lawson Industries Inc., Marvin Windows and Doors, Masonry Information Technologists Inc., MI Windows and Doors, NuAir Windows and Doors, Painter Masonry Inc., PGT Industries, PPG Industries, Protecto Wrap Company, Silver Line Windows and Doors, Simonton Windows, TRACO, and WCI Group Inc. I would also like to thank my faculty adviso r, Forrest J. Masters, Ph.D., and committee members Kurtis R. Gurley, Ph.D. and David O. Prevatt, Ph.D., P.E. for their advice and guidance. This research was supported by the Nati onal Science Foundation (CMMI0729739) and the State of Florida Departme nt of Community Affairs.

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5 TABLE OF CONTENTS Page ACKNOWLEDGMENTS ............................................................................................................... 4LIST OF FIGURES ............................................................................................................... ..........8ABSTRACT ...................................................................................................................... .............11 CHAPTER 1 INTRODUCTION ................................................................................................................ ..13Recent Hurricane Impacts ...................................................................................................... .14Water Penetration Resistance Requireme nts for Residential Fenestration .............................16Scope of Research ............................................................................................................. ......172 WIND-DRIVEN RAIN INGRESS TH ROUGH THE BUILDING ENVELOPE .................23Rainfall Intensity ............................................................................................................ ........23Raindrop Size Distribution .................................................................................................... .24Rainfall Trajectory ........................................................................................................... .......25Wetting of the Building Faade ..............................................................................................26Water Ingress through the Building Faade ...........................................................................28Summary ....................................................................................................................... ..........303 WATER PENETRATION RESI STANCE TEST METHODS .............................................32Uniform Static Air Pressure Difference .................................................................................32Cyclic Static and Cyclic Air Pressure Difference ...................................................................33Pseudo-Dynamic Pressure ......................................................................................................3 5Summary ....................................................................................................................... ..........364 EXPERIMENTAL PROCEDURE .........................................................................................42Testing Apparatuses ........................................................................................................... .....42Negative (Suction) Air Pressure Chamber ......................................................................42Positive (Stagnation) Air Pressure Chamber ...................................................................43Hurricane Simulator ........................................................................................................44Full Scale House Mockup ...............................................................................................45Air Caster Cart ............................................................................................................... ..46Testing Protocols and Sequencing ..........................................................................................46Static Air Pressure Difference .........................................................................................47Cyclic Static Air Pressure Difference ..............................................................................48Dynamic Pressure ............................................................................................................48Water Infiltration Rates ...................................................................................................49Summary ....................................................................................................................... ..........51

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6 5 SPECIMEN DESIGN AND CONSTRUCTION ...................................................................68Wood Frame Wall Specimens ................................................................................................68Masonry Wall Specimens .......................................................................................................6 9Testing Matrix ................................................................................................................ ........70Summary ....................................................................................................................... ..........706 RESULTS ..................................................................................................................... ..........79Assessment of Repeatability during the Test Series ...............................................................79Comparison of Results from Static, Cyclic and Dynamic Test Methods ...............................81Intercomparison of Window Operator Water Penetration Resistance ....................................82Operable Window Infiltration Rate Testing ....................................................................83Summary ....................................................................................................................... ..........857 KEY FINDINGS ..................................................................................................................100Comparison of Test Methods ...............................................................................................100Performance of Window Assemblies ...................................................................................101APPENDIX A: SPECIMEN RECORDS.....................................................................................103LIST OF REFERENCES ............................................................................................................ .119BIOGRAPHICAL SKETCH .......................................................................................................123

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7 LIST OF TABLES Table page 1-1 Ten Costliest Mainland United St ates Tropical Cyclones, 1900-2006 ...................................19 1-2 Saffir Simpson Scale ..................................................................................................... .........19 3-1 Draft AAMA 520 Performance Levels ...................................................................................37 3-2 Summary of Existing Testing Protocols ..................................................................................37 4-1 Pressure Series for Cyclic Pressure Test Method ....................................................................52 5-1 Test Specimen Matrix ...................................................................................................... ........71 5-2 Test Specimen Matrix ...................................................................................................... ........72 6-1 Time to Leakage and Corresponding Pressu re in Uniform Static Pressure Tests ...................87 6-2 Number of Leakage Paths Observed in Uniform Static Pressure Tests ..................................88 6-3 Leakage Paths Observed in Static, Cyclic and Dynamic Tests ...............................................89 6-4 Leakage Path Detection Comparison ......................................................................................90 6-5 Evaluation of Operable Windows With Resp ect to Pressure of First Leakage Path ...............91 6-6 Average Percentage of Design Pr essure for Which Leakage Occurred ..................................91

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8 LIST OF FIGURES Figure page 1-1 Percent of Natural Disa sters over 1.0 Billion Dollars ............................................................201-2 Allocation of In sured Losses since 1984 ................................................................................201-3 Normalized Losses since 1980 ............................................................................................. ..211-4 Paths of 10 Costliest United States Tropical Cyclones ..........................................................211-5 Florida Impacting Hurricanes of 2004 ....................................................................................2 21-6 Hurricane Activity of 2004 and 2005 Seasons .......................................................................222-1 Components of the Rain Intensity Vector ...............................................................................312-2 Typical Drop Size Shapes ................................................................................................. ......313-1 ASTM E331-00 Pressure Loading History ............................................................................393-2 TAS 202-94 Pressure Loading History ..................................................................................393-3 ASTM E2268-04 Pressure Loading History ..........................................................................403-4 ASTM 1105-00 Procedure B Pressure Loading History ........................................................403-5 ASTM E547-00 Pressure Loading History ............................................................................413-6 Draft AAMA 520 Pressure Loading History ..........................................................................414-1 Negative Pressure Chamber.................................................................................................. ...544-2 Electro-Pneumatic Valves .................................................................................................. .....554-3 Calibration Catch Box ..................................................................................................... ........554-4 Posivie Pressure Chamber. ................................................................................................. .....574-5 Direct Drive Hydraulic Motor .............................................................................................. ...584-6 Van-Axial Fan ............................................................................................................. ............584-7 Nozzle .................................................................................................................... ..................594-8 Hurricane Simulator. ...................................................................................................... .........604-9 Hydraulic Lift ............................................................................................................ ..............61

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9 4-10 Roof to Wall Connection .................................................................................................. .....624-11 Air Caster Cart .......................................................................................................... .............624-12 Static Pressure Load Sequence ............................................................................................ ..634-13 Cyclic Pressure Load Sequence ............................................................................................ .634-14 Pressure Time History for Dynamic Test ..............................................................................644-15 Loading Functions for Specimen 017C .................................................................................654-16 Flow Data for Increasing Load Curve ...................................................................................664-17 Last 25% of Data for All Pressure Steps ...............................................................................664-18 Filtered Weight Data (1149 Pa/ 24 psf) Step of Specimen ....................................................675-1 Bolted Channels to Wood Frame Walls. .................................................................................735-2 Designs for Wood Frame Walls. ............................................................................................. 745-3 CMU Wall Specimen Stabilization Channel ...........................................................................755-4 Designs for CMU Wall ...................................................................................................... ......765-5 Awning Window.............................................................................................................. ........775-6 Casement Window ........................................................................................................... ........775-7 Single Hung Window ........................................................................................................ ......785-8 Horizontal Sliding Window ................................................................................................. ....786-1 Load and Unload Curves for Operable Windows Under Negative Load ................................936-2 Load and Unload Curves for Operable Windows Under Positive Load. ...............................956-3 Water Infiltrated at the End of Static Pressure Test ...............................................................966-4 Comparison of Performance of Operable Window Assemblies ..............................................976-5 Typical Infiltration for Casement Windows ............................................................................986-6 Typical Infiltration for Single Hung Windows ........................................................................986-7 Typical Infiltration for Single Hung Windows ........................................................................996-8 Typical Infiltration for Horizontal Sliding Windows ..............................................................99

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10 7-1 Infiltration Paths Through the Right Side of the Operable Sill of Specimen #032. ..............102A1-1 Specimen 001 Records ..................................................................................................... ..103A1-2 Specimen 006 Records ..................................................................................................... ..104A1-3 Specimen 011 Records ..................................................................................................... ..105A1-4 Specimen 019D Records .................................................................................................... .106A1-5 Specimen 020B Records .................................................................................................... .107A1-6 Specimen 022 Records ..................................................................................................... ..108A1-7 Specimen 025 Records ..................................................................................................... ..109A1-8 Specimen 032 Records ..................................................................................................... ..110A1-9 Specimen 043 Records ..................................................................................................... ..111A1-10 Specimen 048 Records .................................................................................................... .112A1-11 Specimen 049 Records .................................................................................................... .113A1-12 Specimen 054 Records .................................................................................................... .114A1-13 Specimen 064 Records .................................................................................................... .115A1-14 Specimen 067 Records .................................................................................................... .116A1-15 Specimen 070 Records .................................................................................................... .117A1-16 Specimen 073 Records .................................................................................................... .118

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11 Abstract of Thesis Presen ted to the Graduate School of Civil Engineering at the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Engineering COMPARISON OF WIND-DRIVEN RAIN TEST METHODS FOR RESIDENTIAL FENESTRATION By Carlos R. Lopez December 2009 Chair: Forrest J. Masters Cochair: Kurtis R. Gurley Major: Civil Engineering While recent changes in building codes have resulted in better structural performance during tropical cyclones, water intrusion through the building envelope continues to be a recurring issue. As a result, i ndustry and code officials have vo iced a need to reevaluate the standardized test methods in place for product approval. Under the oversight of a task force that includes representatives from product manufacturing, homebuilding, architecture, engin eering, insurance, code development and test laboratories, these methods have been investigat ed through a series of tests that examines full scale wall/window specimens subjected to simulate d wind driven rain (WDR) scenarios. These WDR events were simulated using a pressure chamber, in which full-scale residential wall systems were subjected to uniform, linearly vary ing, and cyclic pressure loads while the faade was wetted. The specimens were also subjecte d to dynamic loads using a new turbulent wind load simulation apparatus developed at the Univers ity of Florida (UF). It was discovered that the static and cyclic pressure testi ng procedures used in the experime nt described herein replicated the results observed in the dynamic pressure te st reasonably well. Ho listic testing of the

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12 specimens also yielded results that demonstr ate the importance of testing products as an assembly rather than in isolation.

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13 CHAPTER 1 INTRODUCTION Since 1980, ninety natural hazard events have cost the U.S. mo re than one billion dollars individually [1]. The most cost ly of these events are tropical cyclones (see figure 1.1, data from [1]). One-third of these hurricanes have caused an excess of one billion dollars in damages They are more destructive than tornadoes, s now storms, and terrorism combined, accounting for 47.5% of insured losses since 1984 (figure 1-2, data from [6] and [7]) and amounting to approximately $1.09 trillion dollars of damage since 1900 [3]. Florida, which is the most hurri cane prone state in the U.S., is affected by 40% of all U.S. landfalling hurricanes. Two of the three Sa ffir Simpson Hurricane Scale (SSHS) Category 5 storms on record have made landfall in Florida, a nd 39% of major storms have affected this state [4]. Of the 10 most costly hurricanes impacti ng the U.S., eight made landfall in Florida (see table 1.1) [4]. Between 1987 and 2006, $138 billion in insurance claims were paid to policy holders [6, 7]. Floridas susceptibility to hu rricanes is also a function of its population density, which has grown 85% (approximately $9.7 to 18.3 million) from 1980 to 2008, and expected to further grow from 18.3 million current re sidents to 28.7 million residents in 2030 [5a]. The implications of such a rapid increase in popul ation is represented by the possi bility of the next Category 5 storm yielding damages exceeding $80 billion do llars [6, 7] if it st rikes a major population center. Preventative measures must be taken in order to lessen the effect of tropical cyclones on residential structures. Thus, indus try and code officials have voi ced a need to reevaluate the standardized test methods in place for the product approval of fene stration products. The research herein addresses the mitigation of wa ter ingress through wall systems with integrated

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14 fenestration. It focuses on th e water penetration resistance test methods used in the product approval process for building code s in hurricane-prone areas. Th is chapter presents a brief historical perspective on recent hurricane impact s, discusses water ingress through fenestration, and provides an overview of the sc ope of work for this research. Recent Hurricane Impacts On August 24, 1992, Hurricane Andrew struck southeast Florida with sustained wind speeds of 64.72 m/s (145 mph) and set the record as the most costly catastrophe of the 20th century. It caused $26.5 billion in damage and is second only to hurricane Katrina, which was responsible for $81.0 billion in damage [4]. Th e damage of Hurricane A ndrew was quantified in a report commissioned by then Florida Gover nor Lawton Chiles as (Executive order 92-291, 1992): 135,446 homes damaged or destroyed 82,000 businesses damaged or destroyed 7,800 businesses closed 86,00 people unemployed The devastation brought on by Hurricane Andr ew raised many questions about building performance. Many government agencies subsequen tly began to investigat e the effectiveness of the building codes and code compliance. The Federal Emergency Management Agency (FEMA) assembled a team to survey the failures and found problems with inadequate designs, poor workmanship, misapplication of building materi als, improper review of construction permit documents, shortages of inspection staff, as well as deficient training of inspecting staff [9]. These findings led to changes that intended to im prove the wind resistance of new buildings in Florida, including a tripling of the number of r oofing inspectors in Dade County [6, 7]. New standards were also implemented in the building code, such as the incorporation of window and

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15 door standards that mandate the us e of hurricane shutters or impact resistant glass, as well as a mandatory review of plans by cer tified engineers [6, 7]. With the exception of Hurricane Opal (1995) Florida went without a notable landfall during the next 10 years. In 2004 a record 27 disa ster proclamations were issued for hurricanes [10]. Florida was affected most severely, expe riencing Hurricanes Charlie, Frances, Ivan, and Jeanne [10]. The damage in parts of Florida was magnified by the concurrence of both time and location of Charley, Frances and Jeanne (see figu re 1-4). Jeanne and Frances followed almost identical paths and overlapped regions of Florid a already affected by Hurricane Charley. The three storms were separated by 28 days (Landf alls: Charley August 13th, Frances September 5th, and Jeanne September 25th [11]). The most active season in recorded hist ory occurred the following year. The 2005 hurricane season was one that exceeded many previ ous records [4]. Tropical storms formed beyond the end of the Atlantic hurricane season as far as January 2006 (Zeta: Dec 30th to Jan 6th [11]). Seven major hurricanes and a record f our hurricanes reached Category 5 strength on the Saffir-Simpson scale (Emily, Katrina, Rita, and Wi lma [11]). Hurricane Katrina holds the record for costliest disaster at $81.0 b illion dollars [4]. Together the 2004 and 2005 produced 7 of the 9 costliest hurricanes to occur in the U.S. Thes e seasons had a combined 43 named storms, 15 of which made landfall on the United States costing an estimated $142 billion dollars in damage. FEMA Mitigation Assessment Teams were task ed to investigate bui lding performance and found that main wind force resisting systems designed to post-Andrew building codes were effective in withstanding extreme wind loads [1 0]. However, extensive damage occurred to component and cladding systems, particularly through water ingress. In report FEMA 490, the majority of building damage was attributed to insufficient wind resistance of building envelope

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16 systems which allowed wind-driven water infiltr ation into buildings, resulting in contents damage and loss of function. Furthermore, the au thors stated that the performance of building envelope systems in high wind events requires attention. Design guidance and code changes are needed. This research specifi cally addresses this concern with regard to performance of the window-wall systems, i.e., the window, wall, and interface (defined by the installation technique). Water Penetration Resistance Requiremen ts for Residential Fenestration There are many field and laboratory test met hods that evaluate th e water penetration resistance of fenestration. These include st atic pressure tests (e .g., TAS 202-94 [47], ASTM E331-00 [41], Procedure A of ASTM E1105-05 [43] and ASTM E547-00 [42]), cyclic static pressure tests (e.g., TAS 203-94 [48], JIS A 1517 [46],and Procedure B of ASTM E1105-05 [43]), cyclic pressure tests (e.g. ASTM E2268-04 [44]), and dynamic tests (e.g., AAMA 501.105 [39]). These tests stipul ate a performance criterion, su ch as a maximum allowable accumulation of water that overflows the innerm ost plane of the product. Most standards stipulate that the corresp onding load condition be equal to 15% of the structural design pressure (AAMA/WDMA/CSA 101/I.S.2/A 440 [38], TAS 202-94 [47]). The principal question in this research is wh ether these conditions and the experimental design are representative of hu rricane conditions. Moreover, sin ce windows are currently tested in isolation, how do they perform when they are in tegrated into a finished wall system that might propagate leaks into the cavity between the wi ndow and the rough opening of the wall? The literature is scarce on the subject of holistic testing (i.e. testing of construction assemblies rather than products in isolation) which is highly probl ematic considering the wide variety of window options, installation methods, and finished wall systems availa ble today. A thorough understanding of the interaction of these products is essential due to the increasing number

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17 products available. Consider that the numbers of new windows produced each year has increased from 2 per 100 people in 1900 to 11.1 in 2000 [13]. Scope of Research The objectives of this st udy are as follows: Develop a testing procedure that holistically evaluates the performance of the building system, i.e. a finished wall with an integrated window Evaluate existing fenestration testing protocols by analyzi ng these results with those attained from the full scale Hurricane Simulato r at the University of Florida (See Masters et al. [49] and Testing Apparatuses in Chapter 4). Examine the differences in water penetra tion behavior given va rious operable window assemblies. To carry out this research, modified water penetration test met hods were conducted on sixteen full size wall specimens that varied in window size, wi ndow material, operator type, wall construction, exterior finish, and sill type we re constructed for eval uation. Each specimen underwent four individual rounds of testing using static, cycl ic, dynamic, and static load sequences. The static and cyclic pressure te sts were based on existi ng test methods. Water penetration was quantified and comp ared with results from testing using the Hurricane Simulator (detailed in Chapter 6). Tes ting using the Hurricane Simulato r is used as the basis for comparison, given that the wind loading is calibrate d to data collected in the field by the Florida Coastal Monitoring Program (FCMP) since 1999. The specimens were then subjected to a second static pressure test (using the exact pressure loading and wetting as the first static test), to determine if damage occurred during the first th ree tests. Specimens were loaded with both positive and negative pressure to compare their rela tive results. Finally, results from these tests were used to quantify the difference in water pe netration resistance betw een different operator types.

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18 Chapter 2 reviews the literature on the topic of wind-driven ra in ingress through residential windows. An overview of existing water penetration resistance test methods is given in Chapter 3. Chapter 4 summarizes the experimental pro cedure. Specimen design and construction is explained in Chapter 5. Results of the research project are disc ussed in Chapter 6. Chapter 7 contains conclusions and suggestions for new test methods and future research.

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19 Table 1-1. Ten Costliest Mainland Unite d States Tropical Cyclones, 1900-2006 Rank Hurricane Impact Year Internal Pressure Category Damage mbar USD 2006 USD 1 Katrina FL, LA 2005 920 3 81.0B 85.1B 2 Andrew FL, LA 1992 922 5 26.5B 58.6B 3 Wilma FL 2005 950 3 20.6B 21.6B 4 Charley FL 2004 941 4 15.0B 17.1B 5 Ivan FL,AL 2004 946 3 14.2B 16.2B 6 Hugo SC 1989 934 4 7.0B 16.0B 7 Agnes Fl 1972 980 1 2.1B 18.1B 8 Betsy Fl, LA 1965 948 3 1.4B 18.7B 9 Rita LA,TX 2005 937 3 11.3B 11.9B 10 Frances FL 2004 960 2 8.9B 10.2B Table 3a and table 3b from NWS TPC-5 [4] Table 1-2. Saffir Simpson Scale Category Winds Central Pressure Surge Damage m/s mph mbar in Hg m ft 1 33.1-42.5 74-95 >979 >28.9 1.2-1.8 4-6 Minimal 2 42.9-49.2 96-110 965-979 28.5-28.9 1.8-2.4 6-8 Moderate 3 49.6-58.1 111-130 945-964 27.9-28.5 2.4-3.7 9-12 Extensive 4 58.6-69.3 131-155 920-944 27.2-27.9 3.7-5.5 13-18 Extreme 5 69.3 >155 <920 <27.2 >5.5 >18 Catastrophic Table 3a from NWS TPC-5 [4]

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20 Figure 1-1. Percent of Natural Disasters Over 1.0 Billion Dollars Figure 1-2. Allocation of Insured Losses Since 1984

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21 Figure 1-3. Normalized Losses Since 1980 Figure 1-4. Paths of 10 Costliest United States Tropical Cyclones

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22 Figure 1-5. Florida Imp acting Hurricanes of 2004 Figure 1-6. Hurricane Activ ity of 2004 and 2005 Seasons

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23 CHAPTER 2 WIND-DRIVEN RAIN INGRESS TH ROUGH THE BUILDING ENVELOPE Wind driven rain has been an active research t opic for over a century [ 19]. In the area of building science, research of the effects of wind driven rain on building components has remained a difficult task for scientists. This is mainly due to the rapid progress of new and innovative construction materials an d practices. This imbalance has directly led to the inability of building assemblies to withstand WDR loadin g, yielding water ingress. To explain this phenomenon, this chapter will discuss the majo r factors of WDR leading to water ingress through the building faade. Rainfall Intensity Extreme wind-driven rain events begin with the occurrence of rain fall accompanying wind events. Rainfall rates as well as drop size dist ributions can vary throughout the duration of a storm as well as from storm to storm [37]. Rainfall intensity (referred to in different literature as unobstructed rainfall intensity) is defined as the depth of rainfall accumulated per unit of time. Extreme short duration rainfall rates can reac h 1872.0 mm/hr (73.7 in/hr, for one minute in Maryland, 1956) and 432.0 mm/hr (17.0 in/hr for 42 min in Miss ouri, 1947) [37]; however, statistical design rainfall rates are better repres entations. Technical Paper 40 from the National Weather Service prescribes a maximum of 127.0 mm/ hr (5.0 in/hr) for a 100 year return 60 min rain event while most common test standards refer to a prescribed wetting of 203.0 mm/hr (8.0 in/hr, e.g. ASTM E331-00 [41], ASTM E 1105-00, ASTM E2268-04 [44], and ASTM E547-00 [42]). This is the applicati on required to cause water to shee t over a curtain wall, and is the rainfall intensity used in this experiment. There also exists a higher specified rainfall intensity of 274.0 mm/hr (10.8 in/hr, 100 year return 5 min rain event [35]). These design scenarios seem to well encompass rainfall in the no rthern hemisphere which rare ly exceeds 144.0 mm/h (5.7 in/hr)

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24 (0.01% of the time during the rainie st month) [37] and rainfall in tensities gathered from tropical cyclones during the 2004-2006 Atlant ic hurricane seasons that we re a mean of 57.0 mm/h (2.4 in/hr) and a mean hydrometeor diameter of 1.7 0.3 mm (.07 in .01 in) [36]. Raindrop Size Distribution Raindrop size is an important factor in the wetting of the faade. As the next section explains raindrop size affects the tr ajectory of rain. However, befo re analyzing rainfall trajectory it is necessary to understand the effect different micrometeorological factors have on raindrop size distribution. Raindrop size and raindrop size distribution is dependent on wind speed and rainfall intensity. Given a fixed liquid water content, the average hydrometeor size (figure 2-2) is expected to increase proportionally with wind spee d. Raindrop size also varies with number of drops (i.e. the number of raindr ops increases as the drop size decreases [27]. Other less significant factors that affect the drop size dist ribution include the type of rain, and position relative to the center of the storm. Traditionally rainfall distributi on has been presented as a func tion of only rainfall rate and drop size. Work performed by Best explains th is relationship in the distribution expressed in equation 2-1. 25 2) / 2 (1a re F (2-1) Where: 846 0 32 067 30 1 I G I a In this equation F is the fraction of liquid wate r in the air consisting of raindrops of radii < r (mm), I (mm/hr) is the ra infall intensity, and G (mm3/ m3) is the volume of liquid water per unit of volume of air. In this assumption, number of drops increase as dr ops size decreases.

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25 Another rainfall intensity dependant distribution is the modified -distribution (Equation 2-2) where N(D) is the concentrat ion of drops having diameter D, NG is the concentration parameter, is the slope parameter, is the curvature parameter, and D0 is the median volume diameter [37]. D Ge D N D N ) ( (2-2) Where: 160 2 0 4 0 6 0 1681 0 0) 1 ( 10 85 512 160 2 / 5880 5 1571 0 D D M N D M DG Willis and Tattelman [37] sought to validate this distribution by comparing it to approximately 14,000 ten sec samples collected fr om hurricanes and tropical storms from 19751982 at 3000.0 m (9843.0 ft) and 450.0 m (1476.0 ft). What they found is that the model very reasonably characterized the obser ved distributions collected in rainfall rates of upwards of 225.0 mm/hr (8.9 in/hr). However, they also found une xplained differences in the distributions taken at 3000.0 m (9843.0 ft) and 450.0 m (1476.0 ft). Rainfall Trajectory Rainfall trajectory varies primarily due to tw o factors: raindrop size and wind speed. For a particular drop size the forces that act to change its flight pattern are grav ity and drag. The drag forces are Reynolds (Re) number dependent, which ar e determined from the size of the droplet. As droplets form, they are small nearly spheri cal, due to surface tension dominating over the pressure forces. As their velocity increases in higher wind velocities they collide forming larger drops, and the unequal pressure dist ribution distorts the droplet as shown in figure 2-2. Through

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26 out the fall of the droplet these collisions and droplet separations occur multiple times yielding different sized drops. Smaller si zed drops are also susceptible to evaporation throughout [37]. Figure 2-1 depicts the rain vector, which ha s components of horizontal and driving rain intensity [18]. In the freestream case, as the droplets fall downwards through the boundary layer, the rain droplets are assumed to be moving at the grad ient wind speed horizontally and falling at terminal velocity which effectively is a functi on of the drag coefficient. The trajectory, once reaching the obstructed wind flow area, becomes mo re complicated as does the wind flow. As droplets approach the building, the trajectory of the smaller partic les changes more sharply. In contrast the higher inertia, larg er droplets have a less oblique trajectory as well as a more rectilinear trajectory nearing the windward wa ll of the building [18]. In regards to the experiment described herein, the trajectory of rain droplets impinging on the specimens was assumed to be horizontal as it is assumed to be the worst case scenario for water intruding through vertically mounted fenestration. Wetting of the Building Faade The distribution of wetting on the building faad e is highly non-uniform due to the flow characteristics around the building and the traject ory of the rain, which is sensitive to the raindrop size distribution [ 23, 26]. The flow around a building is dependent on upstream conditions, including surface roughness, orientati on of the building in the flow field, and geometric shape. As different buildings are built to different aspect ra tios, the varying local flows affect the deposition of droplets on the buil ding faade. Hence the flow around a structure has to be calculated using a computational flui d dynamics model in which the three dimensional wind velocities are derived and then used to obtain the raindrop trajectories [26]. Quantifying the effect of WDR on a particular structure is accomplishe d by calculating the Local Effect Factors (LEFs) and Local Intensity Factors (LIFs) used by Choi. Other literature

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27 may refer to LEFs and LIFs as specific catch ratio d and catch ratio respectively. The LEF is the ratio of the wetting of a particular locati on on the structure to the unobstructed rainfall intensity in the free stream for a single hydrometeo r diameter, d, and is illu strated in equation 2-3 [24,25]. ) ( ) ( ) ( t d R t d R t LEFh dr (2-3) The equivalent parameter for all raindrop size s on the structure is the LIF. The LIF is obtained by integrating the LEFs over all hydrom eteor diameters in equation 2-4 [24,25]. ) ( ) ( ) ( t R t R t LIFh dr (2-4) With the velocity data obtained from the flow model, the trajectories are computed at every point for each raindrop size by iteratively solv ing their equations of motion (Equation 2-5 through 2-7) in which m is mass of the droplet, r is radius, a is the air density, w is the water density, and is the air viscos ity [26] and x is the along wind direction, y is the cross wind direction and, z is the vert ical direction [24, 25]. 24 ) ( 62 2R C dt dx U dt x d mD (2-5) 24 ) ( 62 2R C dt dy W dt y d mD (2-6) ) 1 ( 24 ) ( 62 2 w a Dmg R C dt dz V dt z d m (2-7) These equations of motion coupled with the drag coefficients of droplet sizes demonstrate that smaller diameter drops are greatly influenced by the flow closer to the structure. Choi demonstrated this with the use of drop size dist ributions by Best and Mualem [20, 21] to analyze a 4:1:1 ratio building. Choi dem onstrated that for LEF values al ong the vertical ou ter thirds, the

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28 top quarter decreases steadily upon increasing droplet size beyond 1.0 mm (0.04 in). In addition, the bottom three quarter LEF values increased steadily upon increasing droplet size beyond 1.0 mm (0.04in). Given raindrop sizes below 1.0 mm (0.04 in), the lower three quarters reach a minimum LEF value at 0.5mm (0.02 in), while th e top quarter continues to decrease steadily. Furthermore in all cases, buildings demonstrated greater LIF values al ong the vertical outer thirds and substantially larger LIF values at the top quarter [24, 25]. Among the factors that affect WDR intensity, the most dominant are the location on the structure (as explained above), building geometry, and wind speed. The effect of varying building geometry, in particular width to height ratios, changes the blockage effect to the wind flow. For higher ratios the number of drops divert ed away from the structure increases. This was also demonstrated by Choi s investigation in which a narrow (H:W:D=4:1:1) building exhibited higher LIF values than a wider (H:W:D= 4:8:2) building (assuming similar drop sizes). Wind speed, as in the free stream case, also a ffects droplet trajectory by forcing droplets to acquire a larger horizontal velocity. The highe r the wind speed the greater the driving rain intensity, therefore more droplets are susceptibl e to striking the buildi ng surface. Choi found that changing wind velocity from 5.0 m/s to 30. 0 m/s (11.2 mph to 67.1 mph) can substantially increase LIF values 10 times for the top quarter of a 4:1:1 ratio buildi ng. That is to say, increasing wind velocity will increase the effect of all raindrop sizes on the building faade particularly in the top quarters. Water Ingress through the Building Faade Once rain droplets strike a building faade, they begin to collect and move across the building face. If unobstructed, the accumulation of water will simply runoff. However, if a penetration through the building enve lope exists (e.g., microcracks in stucco [31]), water will

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29 infiltrate due to the pressure differential, kinetic energy of rain droplets, and gravity and capillary forces [29]. This is a problem that persists although ne wer building codes and st andards have yielded considerable declines in stru ctural damage. In Florida th is was evident during the 2004 hurricane season, which yielded over 1,000 compla ints from new homeowners of water intrusion [30]. The causes for water intrus ion in many of these cases were particularly perplexing due to the lack of obvious infiltration paths (e.g., dama ged roofing materials, fenestration products, or evidence of flooding [30]). Under commission from the Home Builders Asso ciation of Metro Orla ndo and the Florida Home Builders Association, Lstiburek conducted a study to identify the factors contributing to the failure of water penetration resistance in structures. In th is study he identified the primary faults to be those of the performance of stucco claddings, water resistant barriers, windows and doors, service penetrations, soff it vent assemblies, and paint and coating techniques [31]. Blackall and Baker [29] stated that for the case of fenestration there will almost always be paths for water to penetrate unless much effort is put forth in the de sign and construction. Additionally once fenestration produc ts have been installed they are susceptible to building movement causing wracking forces on the casin gs which will likely open paths for water infiltration. Gurley et al. [17] found that the percentage s of homes experiencing water damage due to water intruding through the exterior windows during the 2004 hurricane season were approximately 23% for homes built between 1994-1998, 24% for homes built between 19992001, and 12% for homes built between 2002-2004 [17].

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30 Water penetration resistance performance has prompted several studies to identify the primary contributors of moisture problems. RD H Building and Engineeri ng Ltd. [32, 33] sought to identify the contribution of building codes, standards, testing protocols and certification processes in a study that analy zed the performance of 113 labor atory and 127 field specimens. Their study identified five key issues: The need to address in-s ervice exposure conditions Adequately address water penetration c ontrol at the window to wall interface Better address leakage direct ly associated with the manufactured window assembly Durability of water pe netration performance Provide rational maintenance and renewals guidance for the installed window assembly The research herein builds on the RDH study by (1) evaluating water penetration resistance in hurricane conditions and (2) taking a systems approach to evaluate the performance of a finished wall with integrated fenestration. Summary Wind-driven rain has three major factors that affect the wetting of structures: rainfall intensity, drop size distribution, and trajectory. E ach factor has been reviewed to better represent the phenomenon of WDR and analyze current test standards as we ll as the performance of the specimens. The following chapter will provide an overview and commentary of existing water penetration test methods .

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31 R R a i n I n t e n s i t y V e c t o rRdrDriving Rain IntensityRhHoriz. Rainfall Intensity Wind Velocity Figure 2-1. Components of th e Rain Intensity Vector Figure 2-2. Typical Drop Size Shapes

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32 CHAPTER 3 WATER PENETRATION RESIST ANCE TEST METHODS During tropical cyclones, fenestration products are subjected to extreme wind loads and WDR. Hence, governing bodies of many hurricane prone regions mandate th at these products be evaluated by an accredited laboratory for structur al and water penetration resistance. To assess product performance these laboratories employ repeatable, simplified test methods. The following chapter will provide an overview of these tests. Uniform Static Air Pressure Difference Uniform static air pressure tests are widely used in the product a pproval process (e.g., ASTM E331-00 [41]) and in diagnostic assessm ent of leakage paths in existing structures (Procedure A of ASTM E1105-05 [43]). Pro cedure A in ASTM E1105-05 [43], applies a specified static air pressure over 15 s and maintain s that pressure for 900 s while the test subject receives a specified rate of water spray. ASTM E331-00 [41] preserves the same load time history however it states that test-pressure di fference or differences at which water penetration is to be determined, unless otherwise specified, shall be 137.0 Pa (2.86 psf). (see figure 3-1). For the case of all ASTM tests water penetration is defined as penetration of water beyond a plane parallel to the glazing (the vertical plane) intersecting the innermost projection of the test specimen, not including interior trim and hardware under the specified conditions of air pressure difference across the specimen. In Florida, Testing Application Standard (T AS) 202-94 [47] evaluate s the structural and water penetration performance of fenestration products. It closely resembles ASTM E331-00 [41]. TAS 202-94 structurally tests a window to 150% of the ra ted design pressure, observing maximum and permanent deflections during test ing (see figure 3-2). In regards to water infiltration the fenestration must not exhibit any intrusion when 15% of the design pressure is

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33 applied with a constant water spray applied to the window specimen (see Section 5.2.6 of TAS 202-94 [47]). Cyclic Static and Cyclic Air Pressure Difference Cyclic static pressure tests are also used in the laboratory and the fi eld to evaluate water penetration resistance (e.g. Pr ocedure B of ASTM E1105-05 [ 43], ASTM E547-00 [42], ASTM E2268-04 [44], JIS A 1517 [46], a nd AS/NZS 4284:1995 [45]). Th e two major static cyclic pressure tests are ASTM E1105-05 [43] Proce dure B, and ASTM E547-00 [42]. Both are a determination of water penetration of installed exterior windows, skyli ghts, doors, and curtain walls, however; the major difference is ASTM E1105-05 [43] is strict ly a field test. ASTM E1105-05 [43] procedure B is also very similar to its count erpart, ASTM E1105-05 [43] procedure A, in that it doesnt specify a pres sure median. The difference lies in the loading regime where the duration of the pressure cycle shall be 5 min followed by a decrease to ambient pressure in a period of not less than 1 min (s ee figure 3-4). The number of cycles is also unspecified and left to the govern ing body requesting the test. Howe ver, it stipulates that In no case shall the total time of pressure application be less than 15 min resulting in a minimum of 3 cycles. ASTM E547-00 [42] is a variation of ASTM E331-00s [41] loading function. The difference is the time of load has to be specified as well as the number of cycles (see figure 3-5). ASTM E2268-04 [44] is a cyclic pressure test defined by a rapi d pulsed air pressure difference. ASTM E2268-04 [44] is similar to the Japanese Industrial Standard JIS A 1517 [46] which uses the same loading func tion, however; it states that the median test-pressure difference or differences at which water pene tration is to be determined, unless otherwise specified, shall be 137.0 Pa (2.86 psf) (see figure 3-3). The lo ading function JIS A 1517 [46] is a modulation limited to 50% of the median pressure with pulse lengths of 2 seconds.

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34 Salient points of these te sts are now discussed. Fenestration products come in a wide variety of design pressures and all have the potential to perform differently. A default minimum of 137.0 Pa (2.86 psf), in existing static pressure tests, rather than a percentage of the design pressure may not suit the requirements necessary in all areas. This issue becomes appa rent in a location such as Florida where the lowest pressure rating for any window sold is approximately 1440.0 Pa (30.0 psf) and 15% of which is 216.0 Pa (4.5 psf). Therefore a ll windows intended for use in Florida would pass ASTM E331-00 [41] without meeting thei r lower bound infiltration criteria. While this issue is accounted for in TAS 202-94 [47] by specifically st ating that the pressure shall not be less than 15% of the design pressure, it is a standard that is only used in Florida. TAS 203-94 [48] excludes the use of 137.0 Pa (2 .86 psf) as a passing criteria for water intrusion. It is done intr insically by mandating the successf ul completion of TAS 202-94 [47] prior to performing TAS 203-04 [48]. It should be noted that this is only for Florida. Additionally there is no stipul ation on how to test for, quantify or record any water infiltration. Infiltration rates or observing mi nimum pressures at which the products exhibit water infiltration are not observed. ASTM E2268-04 [44] section 5. 3 states: As the specified or median test pressure is increased, the maximum test pressure in this procedure is also increased to 1.5 times the specification median test pressure. This higher maximum test pressure may not be representative of actual bu ilding service conditions. For this reason the maximum recommended median test pressure is 480. 0 Pa (10.0 psf), which corresponds to a maximum test pressure of 720.0 Pa (15.0 psf). Testing of products to 720.0 Pa (15.0 psf) to view water penetration behavior may not be sufficient and requires further research and discussion. No distinction in performance is made from pr oduct to product. Factors such as infiltration rates or minimum pressures at which the pr oducts do exhibit water infiltration are not observed. Such factors may play a major role in the insurable dama ge incurred and merit further study which cannot be obtained from minimum performance standards. The test pressure load varies considerably from in situ dynamic pressure s. This is an issue which has been commented studies such as chapter 4 of Summary Report on Building Performance: 2004 Hurricane Season [10]. There are no strategies or s tipulations provided for differe nt wind-driven rain exposure conditions (i.e. climate zones). This raises the question if water penetration resistance should be related directly to wind expos ure zones and merits further research. Age effects are not considered. UV, ozone and environmental exposures, over time, adversely affect the water penetration resi stance of fenestration components such as weather-stripping and sealants [ 13]. Aging of the finished wa ll system may also yield new infiltration paths. The benefits of testing artificially aged assemblies merits further study [13, 50, 51, 52]

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35 These standards test specimens in isolation. Testing of the fenestration product as well as the interface is necessary to assess the performance of the assembly. These standards do not account for the loads fe nestration products are exposed to when installed in structure. Fene stration products are inherently susceptible to the movement structures experience [29] (due to different physical loads, expansion due to heat, etc.). This redistribution of loading may open new migration paths for water and merits further research. The American Architectural Manufacturers A ssociation made similar notes of existing standards and has recently draf ted a Voluntary Specification for Rating the Severe Wind Driven Rain Resistance of Windows, Doors and Unit Sky lights (AAMA 520 [40]). The concept is to apply a spectrum of pulsating pressure and rain loads to determine how well a product performs in wind driven rain over a range of severities. The product receives a scor e on a scale of 1 to 10 based on its ability to prev ent a volume of water greater than 15mL from entering the structure (see table 3-2 and figure 3-6). This is a significant depa rture from the usual practice of test standards, which are based on pass/fail criteria (minimum perf ormance standards). Pseudo-Dynamic Pressure In 2005, AAMA drafted a voluntar y specification that tests pr oducts for water penetration using dynamic pressure (AAMA 501.1-05 [39]). It utilizes a spray system in compliance with ASTM E331-00 [41] and a wind generating device, su ch as an aircraft propeller, (that) shall be capable of producing a wind stream equivalent to the required wi nd velocity pressure. The wind generating device is calibrated to produce minimum of 3 test pressures (from 300 Pa, 380Pa, 480 Pa, 580 Pa, and 720 Pa) at four radi ally equidistant locations. The wind speed tolerance shall be within .1 m/s (.5 mph) of the desired calcul ated wind speed. The test consists of applying the specified wind stream and spray for a period of 15 minutes. Water infiltration is then documented, quantified, and defined as as any uncontrolled water that appears on any normally

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36 exposed interior surfaces, that is not contained or drained back to the exterior, or that can cause damage to adjacent materials or finishes. While this test attempts to more accurately reproduce field conditions, it raises a concern by allowing wind generators such as a propeller. Intrinsically by using a propeller without a method for flow straightening, the flow field is radially nonuniform and possesses significant vorticity. The velocity field produced by the prop eller increases radially outward from the center of the propeller, resulting in pressures at the pe rimeter being much greate r than those nearing the center. In extreme cases there may even be a fl ow reversal near the center of propeller. Given this phenomenon the calibration procedure is no t effective since pressu re measurements are taken at locations are that are radially equidistant from the cen ter and by definition should yield similar pressures. In addition there is an indu ced spiral component of motion to rain droplets which would wet the face of the specimen unnatura lly and may cause or inhibit water intrusions that are representative of service conditions. Summary In most hurricane-prone regions, fenestration mu st be tested by an accredited laboratory to determine its capacity to resist uniform static pressure loads and water ingress. Products must meet or surpass the requirements in these existing standards (a summary is given in table 3-3). The intention is that these pr oducts shall provide sufficient re sistance to wind forces as to maintain the integrity of the building enve lope. The next chapter will comment on the experimental procedure a dopted and its development.

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37 Table 3-1. Draft AAMA 520 Performance Levels Performance Level Lower Limit Median Upper Limit 1 239.4 Pa (5.0 psf) 478.8 Pa (10.0 psf) 718.2 Pa (15.0 psf) 2 284.3 Pa (6.0 psf) 574.6 Pa (12.0 psf) 852.8 Pa (18.0 psf) 3 335.2 Pa (7.0 psf) 670.3 Pa (14.0 psf) 1005.5 Pa (21.0 psf) 4 383.0 Pa (8.0 psf) 766.1 Pa (16.0 psf) 1149.1 Pa (24.0 psf) 5 340.9 Pa (9.0 psf) 861.9 Pa (18.0 psf) 1022.8 Pa (27.0 psf) 6 378.8 Pa (10.0 psf) 957.6 Pa (20.0 psf) 1136.4 Pa (30.0 psf) 7 526.7 Pa (11.0 psf) 1053.4 Pa (22.0 psf) 1580.0 Pa (33.0 psf) 8 574.6 Pa (12.0 psf) 1149.1 Pa (24.0 psf) 1723.7 Pa (36.0 psf) 9 622.4 Pa (13.0 psf) 1244.9 Pa (26.0 psf) 1867.3 Pa (39.0psf) 10 670.3 Pa (14.0 psf) 1340.7 Pa ( 28.0 psf) 2011.0 Pa (42.0 psf) Table 3-2. Summary of Existing Testing Protocols Test Name Type of Load Specified Load Specified Number of Cycles Objective Product Applicability ASTM E331 Static 137 Pa (2.86 psf) N/A Water penetration Exterior windows, skylights, doors, and curtain walls ASTM E1105-05 Procedure A Static Unspecified N/A Field determination of water penetration Exterior windows, skylights, doors, and curtain walls TAS 202-94 Static 75%, 150%, and 15% of DP N/A Structural, water penetration, air infiltration, forced entry Any external component which helps maintain the integrity of the building envelope ASTM E1105-05 Procedure B Cyclic Static Unspecified Minimum of 3 Field determination of water penetration Exterior windows, skylights, doors, and curtain walls ASTM E547-00 Cyclic Static 137 Pa (2.86 psf) Unspecified Water penetration Exterior windows, skylights, doors, and curtain walls ASTM Cyclic 206.0 Pa (2.5 300 Water Exterior

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38 E2268-04 psf), 137.0 Pa (2.86 psf), 69.0 Pa 1.4 psf penetration windows, skylights, and doors AAMA 520 Cyclic See table 3-2 300 per level see table 3-2 Water penetration Windows, doors and unit skylights AAMA 501.1-05 PseudoDynamic 300.0 Pa (6.2 psf), 380.0 Pa (8.0 psf), 480.0 Pa (10.0 psf), 580.0 Pa (12.0 psf), and 720.0 Pa (15.0 psf) One 15 min cycle at a time Water penetration Windows, curtain walls and doors

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39 137 Pa (2.86 psf) 15 sec15:15 min 0 Pa (0 psf) ASTM E331 00 Water spray Figure 3-1. ASTM E331-00 [ 41] Pressure Loading History 0 Pa (0 psf) TAS 202 94 Water spray 150% of Design Load 75% of Design Load 75% of Design Load 150% of Design Load 30 secs 30 secs 30 secs 30 secs 1 5 mins 1 5 mins 15% of Design Load For 15 mins Figure 3-2. TAS 202-94 [47] Pressure Loading History

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40 0 Pa (0 PSF) 1 min 1 min 10 min Water spray 2 sec 68.5 Pa (1.43 PSF) 137 Pa (2.86 PSF) 205.5 Pa (4.29 PSF) ASTM E2268 04 Figure 3-3. ASTM E2268-04 [ 44] Pressure Loading History Specified Pressure 0 Pa (0 psf) ASTM 1105 00 Procedure B Water spray 1 min Specified Number of Cycles 1 min 1 min 5 min Figure 3-4. ASTM 1105-00 [43] Pro cedure B Pressure Loading History

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41 137 Pa (2.86 psf) 15 sec Specified Time 0 Pa (0 psf) ASTM E547 00 Water spray 1 min max Figure 3-5. ASTM E547-00 [ 42] Pressure Loading History 10 min 300 cycles Water spray 2 sec Draft AAMA 520 Level 1 Level 2 Etc. 0 Pa (0 psf) Figure 3-6. Draft AAMA 520 [40] Pressure Loading History

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42 CHAPTER 4 EXPERIMENTAL PROCEDURE Testing Apparatuses This chapter presents information about the custom-built experimental apparatuses constructed to perform the static, cyclic and dynamic load tests. Two static air pressure chambers were constructed to simulate positive and negative (suction) loads, and both configurations allow for uniform and cyclic pressu res. These apparatuses were constructed with the oversight of two product appr oval laboratories: Ce rtified Testing Laboratories, Orlando, FL, and Architectural Testing Inc., York, Pennsylvania. Their input was sought to achieve one of the objectives of this research, which was to adapt the research grade tes ting for simplified product approval testing. Finally, dynamic testing wa s performed on a full sc ale residential house mockup, which was designed to accommodate re movable wall sections. UFs Hurricane Simulator was then used to subject the specimens to a designed load history. Descriptions of each testing apparatus are as follows. Negative (Suction) Air Pressure Chamber UF constructed a negative air pr essure chamber, which consists of a 26.4 mm (1 in) thick acrylic sheet mounted on a steel frame measuring 2.4 m x 2.4 m x 0.3 m (8.0 ft x 8.0 ft x 1.0 ft). It was designed to have a large unobstructed viewing area with minima l steel reinforcement while maintaining a maximum deflection of 1.6 mm (1/16 in) during the peak design pressures of 2873.0 Pa (60.0 psf) (see figure 4-1). HP-33 series Cadillac ce ntrifugal blowers operating in parallel provide the required pr essure and airflow (function of leakage). The blowers are capable of producing a pressure differential of ab out 2394.0 Pa (50.0 psf) at approximately 4.35.6 m3/min (150.0 196.0 CFM), which exceeds 50% of the highest pressure rating of any specimens in this study. Pressure was modul ated by two 106.0 mm (4.0 in) Bray Series 20

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43 electro-pneumatic valves operated by a custom active cont rol system under the control of National Instruments Labview 8.5 software (sho wn in figure 4-2). One valve controls the suction line from the chamber to the blowers, and the other va lve vents the chamber to the atmosphere. These valves work in unison in order to perform the test cycles. Pressure feedback is provided by an Ashcroft XLdp transducer accurate to 6.2 Pa (0.1 psf). Two Baluff bod63mlb02-f115 laser distance measurem ent devices monitor specimen defl ection. One of the lasers measures total deflection of the glazing and the other measures the total deflection of the rough opening (R.O.). Subtracting the R.O. displacem ent from the glazing displacement yields the deflection of the window relative to the frame. Simulated rain was transmitted from a spra y rack composed of nozzles spaced on a uniform grid to wet the entire sp ecimen evenly. The rack was sp aced a fixed distance from the specimens and calibrated (with aid of a pre ssure gauge) to deliver 3.4L/m2*min (5.0 U.S.gal/ft2*hr) in accordance with ASTM E1105-05 [43]. Calibration of the rack was achieved by placing a 610.0 mm (24.0 in) catch box, divided in to four even sections, at the at both upper corners and at the quarter point of the horizontal centerline of th e spray system and 50.8 mm (2.0 in) from the specimen (see figure 4-3). When th e calibration was completed the water pressure to the inlet of the spray rack was recorded to in sure the calibration for every test. A sump pump in the catch basin of the rain ch amber collected the water and reci rculated through a filter back to a 757 L (200 gal) tank. A fluorescent yellow, ultraviolet tracer dye was a dded to the reservoir to improve the detection of leaks (see figure 4-1C). Positive (Stagnation) Air Pressure Chamber Several window manufacturers on the oversight committee raised the issue that water intrusion rates may be dependant of load directio n (i.e., application of positive pressure to the exterior produces different ingress rates than su ction being applied to th e interior). Thus, a

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44 positive pressure chamber capable of achieving 3830.0+ Pa (80.0+ psf) was constructed. To minimize flexing of the frame, 14 gauge galvaniz ed sheet steel lined the inside of a frame consisting of 51.0 mm x 51.0 mm x 3.0 mm (2.0 in x 2 in x 1/8 in) HSS steel tubing spaced at a maximum of 711.0 mm (28.0 in). The spray rack used in the suction ch amber was relocated to this chamber. A Spencer single stage centrifugal bl ower capable of a pressure of 3984.0 Pa (83.2 psf) and an airflow rate of 11.3 m3/min (400 CFM) created the loads. The pressure was modulated through the same electromechanical valves used in the suction chamber. The chamber in its entirety was then transporte d (with the aid of casters) to the specimen. The specimens were fixed to a sta tionary truss prior to attachment with the pressure chamber. In addition the mobility of the chamber allowed for the tightest seal around the specimen (See figure 4-4). Hurricane Simulator UF constructed a 2.09 MW (2800 hp) hurricane simulator capable of replicating turbulent wind and rain loads on a full-size, low-rise struct ure [49]. It is powered by four 522 kW (700 hp) Detroit Diesel marine engine s, which were rebuilt and maintain ed by UF staff and students. Each engine is attached to two tandem Linde 135 cc hydraulic pumps that spin at 2300 rpm. Pressure is then delivered through 165.47 Pa (24,000 PSI) burst pressure hoses to hydraulic motors producing approximately 201.3 kW (270 bhp). The direct drive hydraulic motors (see figure 4-5) in turn spin a 4x2 arra y of vaneaxial fans arranged in a 25.6 m (84.0 ft) circular radius (3.5 angle between fans see figure 4-6). Each Aerovent manufactured fan measures 1.37m (54 in), and equipped with nine adjustable pitch blades delivers 1,700 m^3/min (160,000 CFM). The fans collect air through specially de signed venture inlets that force the air to travel perpendicular to the fan disc for maximum efficiency. The flow is then accelerated through a contraction section reducing the crosssectional area from 6.1 m x 3.1 m (20.0 ft x 10.0 ft), at the fans, to the

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45 test segment of 2.9 m x 2.9 m (9.5 ft x 9.5 ft). Six, custom designed, steel reinforced, neutral shape NACA airfoils are mounted at the trailing edge of the contraction and introduce lateral turbulence as well as rain. The airfoils are co mputer controlled with the use of a 100Hz, 138.3 N-m (1000.0 ft-lb) hydraulic rotary actuator an d a custom active control system built with National Instruments Labview 8.5 software. Wate r is conveyed through an internal network of pipes and injected into the wi nd field along the trailing edge th rough spray nozzles (see figure 47). The pressure regulated nozzles can be calibrated to produce 203.21117.6 mm/hr (8.0-44.0 in/hr) and are arranged in a grid to provide even wetting. The enti re fan array rests on a trailer, making it the largest mobile hurricane simulator in th e world. It is hauled by a tanker truck that also doubles as a 1,8930.0 L (5000.0 gal) radiator The result of all the components is an actively controlled hurricane simu lation capable of wind-driven ra in and 1675.8 Pa (35.0+ psf) stagnation pressures (approxima tely 58.17 m/s, 130mph wind velocities, see figure 4-8). Full Scale House Mockup To test each of the specimens with the Hurricane Simulator, a 4.6 m x 9.8 m x 4.9 m (15.0 ft x 32.0 ft x 16.0 ft) model residential struct ure was constructed. The house mockup was designed in accordance to the Wood Frame C onstruction Manual (WFCM-2001) to withstand wind loads prescribed in ASCE 7 for 67+m/s (150+mph), ensuring its durability. The roof system was to be a standing seam metal roof system to avoid repair after every test, and the roof trusses were designed and manufact ured by a truss company to withstand the same loads. To place the specimens in the correct location of the impinging air flow, the mockup had to be elevated 1.7 m (5.5 ft) on a steel structure built up of 50.8 mm x 50.8 mm x 3.18 mm (2.0 in x 2.0 in x 1/8 in) square tubing. Raising the specimens into place wa s accomplished by employing a 27.0 KN (6,000lb) rated hydraulic lift installed under the mockup (figure 4-9). Once raised the specimens were connected to the roof assembly with a removable pin co nnection (figure 4-10).

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46 Finally, the model was also placed on casters which roll along a track to permit centering of the specimens in the flow field, as well as to clear the area for other testing. Air Caster Cart Transportation of the specimens was also of concern because 25 of the specimens received an application of stucco or decorative cementitio us coating. Cracking of the specimens during transportation would negate the validity of test results. Consequently a custom designed air caster cart was fabricated to tran sport specimens from testing stati on to testing station as well as into the storage facility. The air caster cart is a steel frame that can be assembled and disassembled around specimens (see figure 4-11). It rests on four air cas ters rated for 17.8 KN (4,000 lbs) each, the heaviest of the specimens being approximately 17.8 kN (4,000 lbs). Once loaded, the air casters are pressurized and the sp ecimens are floated on a cushion of air 3.2 mm (1/8 in) thick. In case of accidental depre ssurization, the cart along with the specimen would slowly drop as the casters deflate. Th ese measures insured the utmost care. Testing Protocols and Sequencing Specimens were subjected to four rounds of pr essure loading and water testing. Static, cyclic as well as amplitudeand frequency-modu lated sinusoidal pressure load sequences were applied, followed by a repeat of the static test to ensure that the specimens were not permanently damaged during testing (e.g. cracks forming in the joinery). Such failures would have compromised the investigation teams ability to compare results between the test methods. Therefore as a preventative measure, all of th e following tests were limited to 50% of the windows design pressure. The foll owing static and cyclic pressure tests were composed of their existing counterpart to view their effectiveness as compared to dynamic pressure tests, as well as an amended version to investigat e if newer modified test methods can more closely replicate those obtained from dynamic pressure testing.

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47 Static Air Pressure Difference The static pressure test method borrows fr om Procedure A of ASTM E1105-05 [43] and ASTM E331-00 [41]. ASTM E1105-05 [43] sp ecifies three consecutiv e 300 s cycles while ASTM E331-00 [41] specifies a default of 137.0 Pa (2.86 psf) for uniform static pressure loading. Combination of both yiel ded the initial five minute cycle. A linear increase to 50% of the windows design pressure for the subsequent 15 minutes concluded th e test (as shown in figure 4-12). The rationale for linearly increasing the pres sure over an extended time to 50% of the design pressure is to incorporate the ability to isolate the pressure at which individual infiltrations are first initiated. This pressure along with the location where the infiltration occurred, can be used in comparison with the same data from any other ex periment to view the efficacy of the test (i.e. observe when simila r paths are observed and compare the recorded pressures). This data also provides a level of performance for each specimen by later comparing it to data recorded from other specimens and obse rving the differences in pressure for the initial water intrusions. Specimen definition also changed from the orig inal test methods. In ASTM E1105-05 [43] and ASTM E331-00 [41], the specimen consists of a fenestration product only. In the test methods employed, the specimen consists of the fenestration product integr ated into a finished wall assembly. By testing fenestration in isola tion, products are not subjected to loads that they would be otherwise. In the field fene stration products are subjected to different loads, by means of building movement and temperature changes. These loads contribute to the overall water penetration resistance and merit acknowledgement.

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48 Results from this test were considered the datum for damage incurred to the specimen since it was the first test perfor med. After cyclic and dynamic pr essure tests, this test was reemployed to compare results and detect if dama ge to the specimen had occurred. That is to say, if an infiltration that occurred in the prim ary static test occurred ear lier in the second, or a new infiltration occurred in the second that was unobserved in the first, damage had transpired. Cyclic Static Air Pressure Difference The cyclic pressure test was based on a modi fied version of ASTM E2268-04 [44] and the draft AAMA 520 [40] specification. The specimen was preloaded to 50% of the design pressure for one minute, followed by no load for one mi nute as is the case in ASTM E2268-04 [44]. Cyclic loading immediately followed. The seri es of cycles included those in AAMA 520 [40], although they are preceded by four custom series (see table 4-1). During testi ng the last series of cycles took place when the upper limit of the cycl e approached 50% of the design pressure (see figure 4-13 for illustration). This test method more realistically simulate s the dynamic nature of extreme wind and rain events by recreating sinusoidal patterns based on the energy cascade. In this test method, performance can be quantified by th e level at which the specimen exhibited water infiltration. However, pressure can only be defined over a ra nge, in contrast to the static pressure test method. Therefore, specimen performance can only be compared through fourteen different levels. This still is a great improvement fr om current methods which are minimum performance standards and only test to 205.5 Pa (4.3 psf) or in some cases 720.0 Pa (15.0 psf) (see figure 3-3) which may not be sufficient. Dynamic Pressure The UF Hurricane Simulator was used to pe rform the dynamic testing of the specimens. The loads were designed using 10 minute wind speed observations collected by the Florida

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49 Coastal Monitoring Program that were converted to velocity pressures. It was conservatively assumed that there was perfect aerodynamic admittance between the free stream velocity pressure and the stagnation pressu re on the windward wall. Records with a mean velocity > 20 m/s (44.74 mph) were extracted and detrended. The longitudinal velocity component was calculated and passed through nine bandpass filters in 0.1 Hz passband increments. The peak amplitude for each passband was recorded and di vided by the records 10 minute mean velocity to get a peak amplitude / mean ratio. Data was stratified into three turbulence intensity regimes, of which the middle turbulence ra nge (0.15 0.20) was used. The 50th percentile peak values were employed to construct a sinusoidal loading patte rn at three different ve locity thresholds that correspond to 239.0, 479.0, and 718.0 Pa (5.0, 10. 0 and 15.0 psf). Figure 4-14 illustrates the sequence. Water Infiltration Rates Four wall specimens were subjected to a staircase negative and positive pressure load time histories while a spra y rack applied 3.4L/m2min (5.0 gal/ft2hr) wetting to the exterior face (in accordance with ASTM E1105-05 [43]). Water th at penetrated the window assembly was collected over a specified duration and weighed to quant ify the rate of ingress. It was hypothesized the rate of water ingr ess might behave differently given the progression of loading, particular ly in the lowest pressure regime. Thus the load sequence (shown in figure 4-15) was a pplied forward (incrementing load steps) and backward (decrementing load steps). Specimens were allo wed to dry between the series. The lower and upper bounds of the pressures were confined to the lowest pressure at which the specimen exhibited water ingress and 50% of the windows design pressure in all cases. Step size was determined by dividing the range from the lo wer to upper bound into equal increments. However if the specimen exhibited any peculiar behavior the step size was decreased further.

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50 Once the data acquisition system registered th e desired pressure leve l, research personnel monitored the instantaneous flow rate to determ ine when the infiltration flow had stabilized. This process normally took several minutes. Figu re 4-16 shows the flow for each of the target pressures on the descending load curve of specimen 017C. As is shown in figure 4-17 each of the flows is nearly constant throughout the last 25% of the collection tim e, assuring an accurate measurement of flow. During the test adequate tim e was allotted between pressure steps to allow the water to drain from the collection system a nd specimens before continuing to the subsequent pressure. A collection chamber was designed to collect water that penetrated through the operable portion of each window assembly. This is not to say that water could not migrate from the cavity between the window and the rough opening; how ever, water penetration through the windowwall interface was excluded because of the difficu lty of collecting such minute volumes, what is in some cases, droplets of water or minimal continuous infiltrations through cracks. The collection chamber was also designe d to allow the water to continuous ly transfer (outside of the pressure chamber when performing negative pressures) at the same rate at which it infiltrated the interior side of the specimen. This allowe d continuous recording and monitoring (at 10Hz) by means of an Omega WSB-8150 weight scale co nnected to the same custom active control system (built with National Instruments Labvi ew 8.5 software) that modulated the suction pressure. After the conclusion of the test, pressu re and weight data were post processed using a routine that removes the outliers ( noise) in the data. The first 75% of the data collected is also discarded to remove any variati on in flow do to the initializati on of mass collection. Figure 4-18 illustrates the flow rate using the filtered weight data.

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51 Summary The research team at the University of Florida designed and constructed testing apparatuses to apply modified ve rsions of current test methods. Results from the modified test methods were then analyzed to view particular strengths and limitations and to assess their effectiveness at replicating the dynamic nature of wind and wind-driven rain The results of this analysis are discussed in chapter 6.

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52 Table 4-1. Pressure Series for Cyclic Pressure Test Method Performance Level Lower Limit Median Upper Limit Pa psf Pa psf Pa psf 1* 67.0 1.4 136.5 2.85 205.9 4.3 2* 95.8 2.0 191.5 4.0 287.3 6.0 3* 143.6 3.0 287.3 6.0 430.9 9.0 4* 191.5 4.0 383.0 8.0 574.6 12.0 1 239.4 5.0 478.8 10.0 718.2 15.0 2 284.3 6.0 574.6 12.0 852.8 18.0 3 335.2 7.0 670.3 14.0 1005.5 21.0 4 383.0 8.0 766.1 16.0 1149.1 24.0 5 340.9 9.0 861.9 18.0 1022.8 27.0 6 378.8 10.0 957.6 20.0 1136.4 30.0 7 526.7 11.0 1053.4 22.0 1580.0 33.0 8 574.6 12.0 1149.1 24.0 1723.7 36.0 9 622.4 13.0 1244.9 26.0 1867.3 39.0 10 670.3 14.0 1340.7 28.0 2011.0 42.0

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53 A B

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54 C D Figure 4-1. Negative Pressure Cham ber: A) Wall attached to the pressure chamber. Suction is applied to the interior. B) Interior view of the wa ll specimen looking through 25.4 mm (1.0 in) acrylic. C) Rain Chamber contai ning the spray rack. D) Spray Rack is mounted to the wall exterior a nd sealed to collect water.

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55 Figure 4-2. Electro-Pneumatic Valves Figure 4-3. Calibration Catch Box

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56 A B

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57 C D Figure 4-4. Posivie Pressure Chamber: A.) Wall on permanent stands attached to the fixed truss. B.) Rain Chamber containing the spray rack calibrated to produce prescribed (8.0 17.6 in/hr) wetting. C.) Side view of mounted wall D.) Attached chamber.

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58 Figure 4-5. Direct Dr ive Hydraulic Motor Figure 4-6. Van-Axial Fan

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59 Figure 4-7. Nozzle A

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60 B C Figure 4-8. Hurricane Simulator: A) Tuned inlets that connect to industrial vaneaxial fans. B) Side view of simulator. The inlets and contraction can be removed for travel. C) Hurricane Simulator, residential mode l and specimen being prewetted.

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61 Figure 4-9. Hydraulic Lift

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62 Figure 4-10. Roof to Wall Connection Figure 4-11. Air Caster Cart

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63 Figure 4-12. Static Pr essure Load Sequence Figure 4-13. Cyclic Pressure Load Sequence

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64 Figure 4-14. Pressure Time History for Dynamic Test

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65 A B Figure 4-15. Loading Functions for Specimen 017C

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66 1103 0.01 0.1 1 10 0 0.5 1 1.5 Flow rate variation with timeTime (min)Flow (L/min) Figure 4-16. Flow Data for Increasing Load Cu rve (1149.0 Pa/ 24.0 psf step of specimen 017C) 0 1 2 3 4 0 0.1 0.2 0.3 478.8 Pa (10 psf) 574.6 Pa (12 psf) 670.3 Pa (14 psf) 766.1 Pa (16 psf) 861.8 Pa (18 psf) 909.7 Pa (19 psf) 957.6 Pa (20 psf) 1005 Pa (21 psf) 1053 Pa (22 psf) 1101 Pa (23 psf) 1149 Pa (24 psf) 1197 Pa (25 psf) 1245 Pa (26 psf) 1317 Pa (27.5 psf)Flow vs TimeTime (min)Flow (L/min) Figure 4-17. Last 25% of Data for All Pressure Steps (decreasing pressure curve of specimen 017C)

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67 0 2 4 6 0 5 10 15 Weight of water collected at time tTime (min)Weight (N) Figure 4-18. Filtered Weight Data (1149. 0 Pa/ 24.0 psf Step of Specimen 017C)

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68 CHAPTER 5 SPECIMEN DESIGN AND CONSTRUCTION The 16 wall specimens in table 5-1 were specifi cally constructed for this research, and are discussed in this chapter. Eighteen additional wall specimens were constructed for a companion project, which is detailed in [53]. The specimen matrix from that project is reprinted in table 5-2. Each specimen has a unique combination of win dow operator type (see figures 5-5 through 5-8), window dimensions, window mate rial, window interface (i.e. diffe rent installation methods), wall construction (wood frame and concrete ma sonry) and finish (decorative cementitious coating, stucco, or fiber cement board). Among different variants chosen for the specimens, considerations were also made to safely tr ansport and store the specimens. Specimens were designed to be tested post-cure, therefore they were stored in a warehouse where moisture and sunlight were kept to a minimum in order to avoid unintended aging. Under advisement from the task force it was decided that wall c onstruction should be limited to those typical in residential constructio n. Hence, wood framed walls were designed to 209 kmph (130mph) wind loading and concrete masonry walls were designed to 225 kmph (140mph) wind loading. Wood Frame Wall Specimens Wood frame wall specimens were constructed offsite by a residentia l contractor using design specifications provided by the Ameri can Forest & Paper Association (AF&PA) for minimum code conforming wood frame walls. This was done with the inte ntion of allowing the walls to flex as much as permitted while still meeting deflection requirements set forth for stucco finishes. Once framed, these specimens were sheathed w ith 11.1 mm (7/16 in) oriented strand board and the exterior was wrapped in commercial wrap They were then finished in either fiber

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69 cement board or a three coat (scratch, brown, and finish coats) stucco a pplication, 13.0 mm (1/2 in) thick, over lath. To simulate a wall to slab connection and to keep the walls from deflecting unintentionally, each wall had a st eel channel bolted to the bottom plate (see figure 5-1). Each specimen was braced to the appara tus of every test, as well as the air caster cart, through the channels. This precaution allowed handling and transportation of the sp ecimen without damaging the finish or any other com ponent. Specimens were also kept elevated from the ground approximately 101.6 mm (4.0 in) to access them for transport. Masonry Wall Specimens CMU wall specimens were built onsite, upon a ri gid steel channel, by a licensed masonry contractor. The CMU channel had #5 rebar welded at one fourth and thre e fourths of its length to reinforce the masonry (see figur e 5-3). Two 15.9 mm x 254.0 mm (5/8 in x 10.0 in) bolts were also welded to the channel in order to resi st any moment that wa s developed between the masonry and the channel. Both the rebar and bolt s are intended to help transfer load to the channel, which in turn will transfer the load safely out of the specimen. Each CMU wall was also equipped with grouted cells at the ends and at either side of the window rough opening (see figure 5-4). Rough opening tolerance was in compliance with ACI 530. Upon completion by the mason, the walls were finished with either a decorative cementitious coating (varied from a paint thickness to 6.4 mm, 1/4 in), or a three coat (scratch, brown, and finish coats) stucco application (13.0 mm, 1/2 in) over lath. The stucco application of these specimens was selected with the assistance of Construction Code Specialists (CCS) and the National Concrete Masonr y Association (NCMA).

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70 Testing Matrix In residential construction it is common th at a single home may contain a number of different window sizes and operator types. With a wide range of window options available, the selection of a window is often ba sed on the architectural appearan ce as well as th e functionality it may serve in the desired application. Thes e functions include egress requirements where designers deem necessary, in case of an emergenc y, as well as giving occupants control of the interior environment by natural ventilation. It would be unr easonable to test all possible permutations of window size and type; theref ore, under guidance of leading manufacturers, careful consideration was made to limit the window variants to those most representative of coastal construction pr actice in the south-eas tern U.S. For opera tor types, single hung, horizontal sliding, out-swing casem ent, and awning windows were selected for evaluation. Each of which were limited to one representative window size based on mini mum gateway sizes from residential performance classes provided in AAMA/WDMA/CSA 101/I.S.2/A440 [38]. Within similar operator types and dimensions there are also varying drainage types from window to window (e.g., windows with built-in weep holes). Window material (alu minum and vinyl) was also varied to observe their respective water in filtration resistance. In addition, all of the windows were installed to manuf acturers guidelines. Two in stallation methods for windows were also employed (performances of which were analyzed in [53]). Summary Sixteen specimens were evaluated to observe th eir respective water infiltration resistance. Each specimen was unique its combination of window ; operator type, material, size, installation, and wall; material, and finish. These individu al permutations were subjected to the aforementioned test methods and results were then analyzed.

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71 Table 5-1. Test Specimen Matrix Specimen Wall Window Construction Finish Operat or Dimension Material DP 001 Wood Stucco Fixed 110.49 cm X 158. 75 cm 43.5 X 62.5) Aluminum40 006 Wood FCB Casement 90.17 cm X 151.13 cm (35.5 X 59.5 ) Aluminum40 011 CMU DCC Hor. Sliding 158.75 cm X 110.49 cm (62.5 X 43.5) Aluminum45 020B CMU Stucco Fixed 110.49 cm X 158.75 cm (43.5 X 62.5) Aluminum40 022 Wood FCB Single Hung 110.49 cm X 158.75 cm (43.5 X 62.5) Vinyl 40 025 Wood Stucco Casement 90.17 cm X 151.13 cm (35.5 X 59.5 ) Vinyl 40 032 CMU Stucco Hor. Sliding 158.75 cm X 110.49 cm (62.5 X 43.5) Vinyl 40 019D CMU DCC Fixed 110.49 cm X 158.75 cm (43.5 X 62.5) Aluminum40 043 CMU DCC Single Hung 110.49 cm X 158.75 cm (43.5 X 62.5) Aluminum60 048 CMU Stucco Casement 90.17 cm X 151.13 cm (35.5 X 59.5 ) Aluminum60 049 Wood Stucco Hor. Sliding 158.75 cm X 110.49 cm (62.5 X 43.5) Aluminum60 054 Wood FCB Awning 120.65 cm X 74.93 cm (47.5 X 29.5 ) Aluminum60 064 CMU Stucco Single Hung 110.49 cm X 158.75 cm 43.5 X 62.5) Vinyl 50 067 CMU DCC Casement 90.17 cm X 151. 13 cm (35.5 X 59.5 ) Vinyl 55 070 Wood FCB Hor. Sliding 158.75 cm X 110.49 cm (62.5 X 43.5) Vinyl 60 073 Wood Stucco Awning 120.65 cm X 74. 93 cm (47.5 X 29.5 ) Vinyl 60

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72 Table 5-2. Test Specimen Matrix Specimen Wall Window Construction Finish Operat or Dimension Material DP 017 Wood Stucco Fixed 110.5 cm X 158. 8 cm (43.5 X 62.5) Aluminum40 017B Wood Stucco Fixed 110.5 cm X 158.8 cm (43.5 X 62.5) Aluminum40 017C Wood Stucco Single Hung 110.5 cm X 158.8 cm (43.5 X 62.5) Aluminum55 017D Wood Stucco Fixed 110.5 cm X 158.8 cm (43.5 X 62.5) Aluminum40 017E Wood Stucco Fixed 110.5 cm X 158.8 cm (43.5 X 62.5) Aluminum40 018 Wood FCB Fixed 110.5 cm X 158.8 cm (43.5 X 62.5) Aluminum40 018B Wood FCB Fixed 110.5 cm X 158. 8 cm (43.5 X 62.5) Aluminum40 018C Wood FCB Fixed 110.5 cm X 158. 8 cm (43.5 X 62.5) Aluminum40 018D Wood FCB Fixed 110.5 cm X 158. 8 cm (43.5 X 62.5) Aluminum40 018E Wood FCB Fixed 110.5 cm X 158. 8 cm (43.5 X 62.5) Aluminum40 019 CMU DCC Fixed 110.5 cm X 158.8 cm (43.5 X 62.5) Aluminum40 019B CMU DCC Fixed 110.5 cm X 158.8 cm (43.5 X 62.5) Aluminum40 019C CMU DCC Fixed 110.5 cm X 158.8 cm (43.5 X 62.5) Aluminum40 035 CMU DCC Fixed 120.7 cm X 74.9 cm (47.5 X 29.5 ) Vinyl 52.7 020 CMU Stucco Fixed 110.5 cm X 158. 8 cm (43.5 X 62.5) Aluminum40 016 CMU Stucco Fixed 120.7 cm X 74.9 cm (47.5 X 29.5 ) Aluminum52.7 020C CMU Stucco Fixed 110.5 cm X 158. 8 cm (43.5 X 62.5) Aluminum40 020D CMU Stucco Fixed 110.5 cm X 158. 8 cm (43.5 X 62.5) Aluminum40

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73 A Figure 5-1. Bolted Channels to Wood Frame Walls

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74 Figure 5-2. Designs for Wood Frame Walls.

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75 A B Figure 5-3. CMU Wall Specime n Stabilization Channel

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76 Figure 5-4. Designs for CMU Wall

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77 Figure 5-5. Awning Window Figure 5-6. Casement Window

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78 Figure 5-7. Single Hung Window Figure 5-8. Horizont al Sliding Window

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79 CHAPTER 6 RESULTS The specimens were subjected to four indepe ndent rounds of testing to investigate the effects of differing loading condi tions. The specimens were m onitored for instances of water intrusion, which is defined as any liquid water observed from the interior side of the wall assembly to have bypassed the moisture barr ier of the window/wall system. This chapter discusses the repeatability of test results, its relationship to damage accumulation, and compares the diagnostic abilities of the various tests to de tect leakage. The water penetration resistance of each operator type is evaluated, with particul ar focus on the performance of compression and sliding seals. Finally, the results of positive and negative pressure testing are compared to investigate whether or not anecdotal claims that the direction of pressure loading affects leakage and can be repeated experimentally. Assessment of Repeatability during the Test Series Test specimens were subjected to three water penetration resistance test methods with different pressure loading scenarios, and had to be transported to each of the testing apparatuses and their storage locations. Thus it was necessa ry to determine if successive testing and/or transport caused any permanent damage before results could be compared. Two measures were taken to obviate this issue. First, the maximum pressure applied was intentionally set at half of the windows rated design pressure (DP) to avoid permanent damage to the wall assembly, seals, and window co mponents, which would in turn change water penetration resistance. Second, a custom built air caster cart was developed to literally float the walls from one location to the next. This system worked well; the investigators have no cause to believe that any of the specimens were damaged during transport.

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80 To address the potential outcomes from successive testing, the first test was repeated after the static, cyclic, and dynamic tests (performed in this order). All other factors being equal (e.g., identical mechanical response of the valves, temperature, relative humidity, etc.), the two static pressure tests should produce the same results if the specimens were not permanently damaged in previous tests. The results of the first and last uniform static pressure tests are now discussed. The test data for this project may be found in tables 6-1 and 6-2 (The reader should refer to [53] for the test data from the companion project specimens f ound in table 5-2). Table 6-1 contains initial infiltration paths that occurred at recorded pressures duri ng the separate rounds of static testing. Each row in the tables corresponds to an isolated location where infiltration was observed. Table 6-2 contains the number of l eakage paths observed in each test. Each specimen that exhibited e ither a large change in the pressure threshold associated with the first sign of leakage and/or number of leak s from the first static pr essure test to the last were reanalyzed using other recording methods used during testing (e.g. photographic and video), to determine if indeed damage accumula tion had occurred. The salient points from the re-inspection are listed below. Specimens 019, 020B and 070 exhibited new infiltration paths th rough the window/wall interface during the second static pressure test, demonstrating damage. These test results will be disregarded. Specimen 011 exhibited new infiltration pa ths through the window assembly during the second static pressure test. Its test results will be disregarded. Specimen 067 exhibited new infiltration paths through the precast sill at a lower pressure in the second static test, demonstrating dama ge. Its test results will be disregarded. Specimen 064 should be identified as the onl y specimen that was subjected to 1675.8 Pa (35.0 psf) during the dynamic pressure test. These pressures were s ubstantially beyond the test protocol of 50% of the design pressure (1197.0 Pa /25.0 psf), hence the specimen was deemed to have sustained damage and its results will be disregarded.

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81 During the initial static pressu re testing, research personnel prematurely terminated 2 of the 9 specimen tests (032 and 049) because of concern that th e rate of water infiltration might damage the specimen or overload the dr ainage capacity of the testing apparatus. These were the first tests performed in this proj ect. Further investigation showed that rates of infiltration observed were typical and no dama ge had occurred. In subsequent tests, the testing was carried out through the full duration. Regarding specimens 020D and 025, it is the opinion of the research team that the infiltration paths documented in the second sta tic pressure test were minute and possibly overlooked in the first static pr essure test. They are judg ed to not be indicative of permanent damage. Summarizing, six out of the 34 wall specime ns exhibited a change in performance sufficiently large to warrant their removal from subsequent analysis. For practical purposes it may be assumed that the remaining specimens e xhibited repeatable performance characteristics and that the results are intercomparable. Comparison of Results from Static Cyclic and Dynamic Test Methods Comparing the diagnostic ability of static, cyclic and dynamic tes ting was the principal objective of this project. The ultimate goal is to determine if full-scale dynamic testing should replace the simplified test methods used today or if the simplified tests ar e sufficient to evaluate water penetration resistance in their current form (or with minor modifications). It is important to note that these questions are be ing asked in the context of sys tems testing. Today, products are tested in isolation, which many profe ssionals feel is a major shortcoming. This new understanding is the key to improvi ng simplified, but highly repeatable, test protocols to bridge th e gap between what can be physica lly accomplished and duplicated in commercial testing labs, and what actually occurs in a windstorm (or perhaps, a research-grade windstorm simulation facility). Dynamic pressure testing using the hurricane simulator was assumed to be the better representation of loads exhibited by a windstorm, although it is noted that there stil l remain many deficiencies with the ability of full-scale simulators to recr eate hurricane force winds and wind-

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82 driven rain. The field is stil l in its infancy, and projects su ch as this one are required for experimentalists to hone these techniques. Th at being said, the system was calibrated to a simplified representation of actual field data collected in hurrican es and true wind-driven rain was applied (in contrast to the pressure chamber tests where water is sprayed on the specimen while a pressure gradient is created across the specimen). Table 6-3 contains information about the specimens that exhib ited leakage in the first three rounds of testing. Specimens that did not l eak or experienced permanent damage during the testing are omitted. The number of common leakage paths identified through both dynamic and static testing is listed in the first data column. The second data column contains the number of leakage paths observed in the cyclic and dynamic tests. The dynamic test results compare more favorably to the cyclic test than the static pressure test. Table 6-4 contains the number of leakage paths observed in static and cyclic tests that were not observed in the dynam ic testing. It also contains the number of leakag e paths observed excl usively in the dynamic test, but did not manifest in the static or cyclic tests. The counts are nearly id entical (7,7,8) for the three test methods, which indicates ther e is no clear advantage to the dynamic testing. Summarizing, adapting conventional testing t echniques to holistically test wall systems appears to work well based on the results of thes e experiments. It shoul d be noted that this observation is only strictly valid for the type of construction evaluated in this research, namely single-family residential finished wall systems with integrated fenestration. Intercomparison of Window Operato r Water Penetration Resistance The water penetration resistance of the specimens with operabl e windows is listed in table 6-5. They are grouped by operator type: aw ning (016, 035, 054, 073), casement (006, 025, 048), single hung (017C, 022, and 043) an d horizontal sliding (032, 049) Summary statistics are provided in table 6-6.

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83 All of the operable wi ndows met the requirement that the water penetration resistance must be greater than or equal to th e 15% of the design pressure (sti pulated in Section 5.3.3.2 of AAMA/WDMA/CSA 101/I.S.2/A440 [38] and Sec tion 5.2.6 of TAS 202-94 [47] in Florida) using the leakage definition set forth in ASTM E 331. ASTM E 331 states that leakage is the penetration of water beyond a plan e parallel to the glazing (the vertical plane) intersecting the innermost projection of the test specimen, not including interior trim and hardware, under the specified conditions of air pressure difference across the specimen. Water was observed to collect in the bottom slid er track earlier in the test, thus for completeness, a second pressure threshold is included in table 6-5. This water would have to reach a sufficient elevation head to overtop the back dam to qualify as leak age using the ASTM E 331 definition. The results summarized in table 6-5 de monstrate that those windows that use a compression seals exhibit better watertightness th an the sliding seal windows. None of the awning windows leaked, which based on the limited re sults of this research indicates that the awning style is the preferable option for area pron e to severe wind driven rain. Two of the three casement windows leaked, but a larg er pressure than the sliding seal windows. The single hung windows leaked at the lowest pr essures, but the flow rate th rough the horizontal sliders was much greater. Operable Window Infiltration Rate Testing The testing application standards typically al low for two load configurations. A suction load can be applied to the interior of the specim en, or a positive pressure can be applied to the exterior of the specimen. In either case, the opposite side of the spec imen is open to the free atmosphere. Thus, all other factors being the sa me, the pressure gradie nt should be the same across the specimen.

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84 It has been speculated that the direction of loading can affect the water penetration resistance (vis--vis test results on identical pr oducts using both load scenarios that do not agree). This issue was specifically addressed in one of the stakehol der oversight meetings, which prompted further testing using a positive pressure chamber (all of the tests results discussed so far were obtained using a negative pressure chamber). Four test specimens were tested again using the two pressure chambers. The loads were incremented in a stepwise pattern while the in filtration rate, through th e window assembly alone, was monitored. Results from the testing, which a ppear in figure 6-1 and figure 6-2, are virtually identical. It should be noted th at because the infiltration rate was measured through the window, specimen 070 (deemed to have sustained da mage through the window wall interface) was reintroduced. It should also be noted that compression seal operator type windows were intentionally left out of this experiment because of the difficulty of collecting and measuring the minute volumes of infiltrated water (e.g. figure 6-3) These data suggest that there is no basis to the claim that the direction of loading affects the infiltration rate given that flow rates were nearly identical for a large range of pressures. Moreover, the lowest pressure threshold for which infiltration occurred for both tests compared very favorably. A summary of infiltration flow rates is given in figure 6-4 and typical infiltration paths are provided in figures 6-5 through 6-8. Least squares curve fitting was performed on the data. The infiltration rate through the hung windows appears to be directly proportional to the pressure load, while the relationship between the pressure and infiltra tion rate through the horizontal slid ers is non-linear. Equations for flow and their respec tive coefficients of determination ar e as shown in equations 6-1 through 6-4 for specimens 017C, 022, 049, and 070 respectivel y. P-Pressure(Pa), QFlow rate (L/min).

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85 76 10 28 35 P Q (6-1) 964 02 R 76 0 10 90 13 P Q (6-2) 982 02 R P Pe e Q01 0 4 10 8 610 8 3 67 04 (6-3) 979 02 R P Pe e Q3 410 2 8 10 7 311 24 61 0 (6-4) 995 02 R An investigation as to whether water penetrati on behavior is dependant on prior load rate (i.e. target pressures are achieve d from greater or lower pressu res) was also conducted. In figures 6-1 and 6-2 the infiltration rates are compared as loads are applied in a step wise fashion. It was theorized that once a specimen was brought up to a certain pressure, infiltration rates at any subsequent lower pressure would be greater; however, the data in these figures suggests that infiltration rates are independent of prior pressure levels. Summary Specimens were subjected to static, cyclic as well as amplitudeand frequency-modulated sinusoidal pressure load sequences, followed by a re peat of the static test to ensure that the specimens were not permanently damaged during te sting. Six of the 34 test specimens exhibit different leakage characteristics between the first and last tests. These results were omitted from further analysis (with the exception of specime n 022, which was reintroduced for isolated window testing). It was found that adapting conven tional testing techniques to holistically test wall systems appears to work well based on the results of these e xperiments. Compression seal windows are more watertight than sliding seal windows, with awning windows being the superior option. Finally, positive and negative pressure loading were performed on test

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86 specimens. It was shown that the direction of loading has no effect on the infiltration rates and pressure threshold associated with the first sign of leakage.

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87 Table 6-1. Time to Leakage and Correspond ing Pressure in Uniform Static Pressure Tests Specimen First Static Test Second Static Test Difference Time Pa psf Time Pa psf Pa psf 001 10:54 450 9 DNL DNLDNL N/A N/A 016 DNL DNL DNL DNL DNLDNL N/A N/A 017 DNL DNL DNL DNL DNLDNL N/A N/A 018 18:17 867 18 DNL DNLDNL N/A N/A 018B DNL DNL DNL DNL DNLDNL N/A N/A 018C DNL DNL DNL DNL DNLDNL N/A N/A 018D DNL DNL DNL DNL DNLDNL N/A N/A 018E DNL DNL DNL DNL DNLDNL N/A N/A 019B DNL DNL DNL DNL DNLDNL N/A N/A 019D DNL DNL DNL DNL DNLDNL N/A N/A 020 DNL DNL DNL DNL DNLDNL N/A N/A 035 DNL DNL DNL DNL DNLDNL N/A N/A 048 16:22 1489 31 DNL DNLDNL N/A N/A 054 03:13 1226 26 DNL DNLDNL N/A N/A 073 04:51 139 3 DNL DNLDNL N/A N/A 020D 10:45 503 11 11:09 522 11 19 0 017C 15:00 948 20 15:40 977 20 29 1 064 08:40 402 8 11:22 431 9 29 1 043 09:12 474 10 09:56 527 11 53 1 049 11:25 847 18 10:57 795 17 -53 -1 025 12:40 565 12 11:36 503 11 -62 -1 017B 17:45 843 18 20:00 958 20 115 2 019C 07:20 273 6 06:00 192 4 -81 -2 017E 06:20 215 5 03:18 139 3 -77 -2 020C 06:38 239 5 04:15 139 3 -101 -2 006 15:15 699 15 10:40 828 17 129 3 032 09:30 527 11 11:11 675 14 148 3 017D 19:30 943 20 17:27 819 17 -124 -3 011 10:30 493 10 09:11 369 8 -124 -3 022 07:21 345 7 10:25 603 13 259 5 070 10:12 450 9 11:49 728 15 278 6 019 15:00 958 20 08:55 354 7 -603 -13 067 15:34 977 20 03:57 139 3 -838 -18 020B DNL DNL DNL 11:10 474 10 N/A N/A

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88 Table 6-2. Number of Leakage Paths Obse rved in Uniform Static Pressure Tests Specimen First Static Test Second Static Test New Path in Second Location of New Path 001 1 0 0 Through sealant 016 0 0 0 017 0 0 0 018 1 0 0 Joinery bottom right corner 018B 0 0 0 018C 0 0 0 018D 0 0 0 018E 0 0 0 019B 0 0 0 019D 0 0 0 020 0 0 0 035 0 0 0 048 1 0 0 Through weather stripping 054 1 0 0 Small drop through window wall interface 073 1 0 0 Window wall interface 020D 2 3 1 Screw in right jamb 017C 3 3 0 064 5 5 2 Head jamb, left jamb sash interface 043 3 3 0 049 5 6 2 Lock assembly, head jamb 025 4 4 1 Through compressible seal top left 017B 1 1 0 019C 2 1 0 Through sealant 017E 2 2 0 020C 1 1 0 006 3 2 0 Joinery of operable pane 032 1 3 2 Above operable pane, meeting rail 017D 1 1 0 011 5 6 3 Joinery bottom left corner, joinery top right, Meeting rail 022 4 4 0 070 3 7 3 Sealant, lock assembly, meeting rail 019 1 2 1 Jamb bucking 067 1 1 0 Precast sill 020B 0 1 1 Jamb bucking Note: Damaged specimens are highlighted

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89 Table 6-3. Leakage Paths Observed in Static, Cyclic and Dynamic Tests Specimen Similar Paths in Primary Static and Dynamic Tests Similar Paths in Cyclic and Dynamic Tests 001 2 2 006 2 2 017B 0 0 017C 2 3 017D 0 0 017E 1 1 018 0 1 019C 2 2 020C 0 1 020D 2 4 022 3 4 025 3 4 032 1 3 043 3 3 048 1 0 049 5 4 054 0 0 073 1 1 Total 28 35

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90 Table 6-4. Leakage Pa th Detection Comparison Specimen Paths in Static Not Detected in Dynamic Paths in Cyclic Not Detected in Dynamic Paths Detected Exclusively in Dynamic Description of Paths Not Detected in Dynamic Description of Paths Detected Exclusively in Dynamic 001 1 0 1 Through sealant at window fin Through sealant at window fin 006 0 1 0 Through joinery 017 0 0 3 Sill joinery, Jamb wall interface, Joinery of head jamb 017B 1 2 0 Window/flashing interface 017C 0 0 0 017D 1 1 0 Sealant/flashing interface 017E 0 0 0 018 1 0 0 Sealant/flashing interface 019C 0 0 0 020C 1 1 0 Skip in sealant 020D 0 0 0 022 0 0 1 Meeting rail 025 1 1 1 Crank assembly Through joinery 032 0 0 1 Top of meeting rail 043 0 0 0 048 0 0 0 049 0 0 1 Through joinery of operable pane at top right corner 054 1 1 0 Window/flashing interface 073 0 0 0 Total 7 7 8

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91 Table 6-5. Evaluation of Operab le Windows With Respect to Pressure of First Leakage Path Operator type Pressures (Pa/psf) % of DP Static 2nd Static Lowest DP(Pa/psf) Awning 054 DNL DNL DNL 2872.8/60 N/A 016 DNL DNL DNL 2523.3/52.7 N/A 073 DNL DNL DNL 2872.8/60 N/A 035 DNL DNL DNL 2523.3/52.7 N/A Casement (067 removed) 048 DNL DNL DNL 2872.8/60 N/A 006 699.0/14.6 828.3/17.3 699.0/14.6 1915.2/40 36.5% 025 565.0/11.8 502.7/10.5 502.7/10.5 1915.2/40 26.3% Single Hung (064 removed) 043 474.0/9.9 526.7/11.0 474.0/9.9 2872.8/60 16.5% 017C 670.32/14.0 1149.1/24.0 670.32/14.0 2633.4/55 25.5% 022 890.6/18.6 785.2/16.4 785.2/16.4 1915.2/40 41.0% Hor. Sliding (leak per definition in Chapter 6* 011 and 070 removed) 049 138.9/2.9 138.9/2.9 138.9/2.9 2872.8/60 4.8% 032 138.9/2.9 138.9/2.9 138.9/2.9 1915.2/40 7.3% Hor. Sliding (leak defined per ASTM E 331**, 011 and 070 removed) 049 847.5/17.7 794.8/16.6 794.8/16.6 2872.8/60 27.7% 032 N/A 675.1/14.1 675.1/14.1 1915.2/40 35.3% Note: Two sets of data for Horizontal Sliding ope rator type to differentia te the definitions of leakage. Any liquid water observed from the interior si de of the wall assembly to have bypassed the moisture barrier of th e window/wall system ** Penetration of water beyond a plane parallel to the glazing (the vertic al plane) intersecting the innermost projection of the test specimen, not including interior trim and hardware, under the specified conditions of air pre ssure difference across the specimen \ Table 6-6 Average Percentage of Desi gn Pressure for Which Leakage Occurred Operator type Average percentage of DP when infiltration occurred Awning Did not leak Casement 37.6% (Note: One did not leak and one was damaged) SH/DH 27.7% Horizontal Sliding 6.1% (first sign of leakage) Horizontal Sliding 31.5% (per ASTM E 331)

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92 A 0 0.1 0.2 200 400 600 800 1000 1200 Increasing Load Decreasing Load 15% of DP Curve FitFlow rate (Specimen 017C Single Hung DP 55)Flow (L/min)Pressure (Pa) B 0 0.5 1 1.5 2 0 500 1103 1.5103 Increasing Load Decreasing Load 15% of DP Curve FitFlow rate (Specimen 022 Single Hung DP 60)Flow (L/min)Pressure (Pa)

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93 C 0 1 2 0 500 1000 1500 Increasing Load Decreasing Load 15% of DP Curve FitFlow rate (Specimen 049 Horizontal Slider DP 75)Flow (L/min)Pressure (Pa) D 0 0.5 1 0 500 1000 1500 Increasing Load Decreasing Load 15% of DP Curve FitFlow rate (Specimen 070 Horizontal Slider DP 60)Flow (L/min)Pressure (Pa) Figure 6-1. Load and Unload Curves for Operable Windows Under Negative Load

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94 A 0 0.1 0.2 200 400 600 800 1103 1.2103 1.4103 Increasing Load Decreasing Load 15% of DP Curve FitFlow rate (Specimen 017C Single Hung DP 55)Flow (L/min)Pressure (Pa) B 0 1 2 3 4 0 500 1103 1.5103 2103 2.5103 Increasing Load Decreasing Load 15% of DP Curve FitFlow rate (Specimen 022 Single Hung DP 60)Flow (L/min)Pressure (Pa)

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95 C 0 1 2 0 500 1103 1.5103 Increasing Load Decreasing Load 15% of DP Curve FitFlow rate (Specimen 049 Horizontal Slider DP 75)Flow (L/min)Pressure (Pa) D 0 0.5 1 0 500 1103 1.5103 Increasing Load Decreasing Load 15% of DP Curve FitFlow rate (Specimen 070 Horizontal Slider DP 60)Flow (L/min)Pressure (Pa) Figure 6-2. Load and Unload Curves for Oper able Windows Under Positi ve Load (Curve-fit is from negative pressure testing)

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96 Figure 6-3. Water Infiltrated at the End of Static Pressure Test (bottom left corner of specimen 006/ Casement window)

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97 Figure 6-4. Comparison of Performa nce of Operable Window Assemblies

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98 Figure 6-5. Typical Infiltra tion for Casement Windows (Botto m left corner above sill) Figure 6-6. Typical Infiltra tion for Single Hung Windows (Bo ttom right corner above sill)

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99 Figure 6-7. Typical Infiltra tion for Single Hung Windows (L eft side of meeting rail) Figure 6-8. Typical Infiltration for Horizo ntal Sliding Windows

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100 CHAPTER 7 KEY FINDINGS Comparison of Test Methods Specimens were subjected to static, cyclic as well as amplitudeand frequency-modulated sinusoidal pressure load sequences to observe water infiltration be havior. Analysis of the data compiled from the 34 specimens generated the following key observations regarding the testing methods: The current water penetration test methods for fenestration evalua te residential window performance in isolation. The results of this testing unequivocally demonstrate that additional leakage paths can occur in the wa ll and at the window-wall interface, which clearly indicates that the mode rn product approval process is deficient in addressing realworld leakage in the context of building systems performance. Based on the limited testing discussed herein, no clear advantage in diagnostic capability was found using dynamic simulation to evaluate the water penetrati on resistance of wall systems with integrated windows. This conclu sion is only strictly valid for single family residential systems. It is presently unknown if these results are exte nsible to cladding and curtain wall systems, and these results likely ha ve absolutely no bearing on roof systems, which are subjected to entirel y different turbulent load conditions. Moreover, it is expected that in order to simultaneously compare wall and roof system performance in a laboratory setting, it will be necessary to im plement full-scale dynamic testing at sufficient scale to envelope an entire building. The cyclic pressure test yielded more infiltration paths than the static pressure test, but the static pressure is a better choice to identify smaller leaks once they form (see figure 7-1 for an example). The pulsating pressure load cau ses an oscillating move ment in the window assembly not recreated in the static test. T hus inertial effects are captured, which more closely resembles the expected response of a flexible system being acting upon by a buffeting load. Thus it may be useful to combine tests, with the static component following the cyclic testing The direction of loading (posit ive vs. negative pressure appli cation) was found not to affect steady leakage rate nor the pressu re threshold associated with the first sign of leakage. Tests were conducted in a highl y controlled environment using research grade equipment, thus it is recognized that other logistical issues associated wi th experimental testing might create conditions that produce different results for each direction of loading. The current cyclic pressure tes ting methods prescribe a square wave load function. It is strongly suggested that a sinusoi dal function should be substituted. The rationale is as follows. First, reproducing a square wave is physically unrea lizable. Mechanical systems cannot simulate discontinuous pressure loading functions. Second, a ramp up or down is

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101 required to shift from one pressure state to a nother. As the duration of this ramp becomes shorter, the possibility of ove rshooting the target pressure value becomes larger, which is highly problematic. Third, the most comm on practice in atmospheric science and wind engineering is to decompose wind and pressure into sinusoidal functions using a Fourier transform. Deviating from this practice is unnecessary and puts unnecessary experimental burden on the testing laboratories. Performance of Window Assemblies As expected, operable window assemblies exhib it larger rates of wa ter infiltration than fixed windows. The test methods performed ai med to observe the effects that different components had on the water penetration resi stance of the window assembly. Among the variables were wall material, window material, window design pressure, and window operator type. Analysis of the data compiled from the 16 specimens that had operable windows installed, generated the following key observations rega rding the water penetration resistance: Specimens utilizing windows with compression seals performed better than those with sliding seals (table 6-6). Awnings performed the best of all specimens. In windows utilizing sliding seals, it was observed that the operable pane separated from the seal. This allowed a gap for air and water to intrude along the interface (e.g. through jamb/sash interface for single hung window) Compression seal operator type windows exhibi ted a substantial improvement in relative water penetration resistance (i.e. infiltration occurring at percentages of design pressure) with increased design pressure: Of the eight different compression seal operator type windows only the lowest rated (1915.0 Pa/ 40. 0 psf design pressure) exhibited water infiltration (table 6-5). However it is unclear whether sliding seal operator type windows demonstrate depreciation or improvement in relative water penetration resistance (i.e. infiltration occurring at percen tages of design pressure) with increased design pressure. Design pressure should not be considered an indication of performance in regards to infiltration flow rate, particularly given highe r pressures: It is more of a dependence on operator type. During these tests it was observe d in some cases, that the highest design pressure rated specimen exhibited the highest fl ow rates. Figure 6-1 shows that horizontal sliding operator type windows follow a non linear pressure to flow re lationship, and single hung operator type windows follow a first order, linear pressure to flow relationship.

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102 A B Figure 7-1. Infiltration Paths Thr ough the Right Side of the Operab le Sill of Specimen #032. A) End of the cyclic test B) End of the static test.

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103 APPENDIX A: SPECIMEN RECORDS Figure A1-1. Specimen 001 Records

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104 Figure A1-2. Specimen 006 Records

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105 Figure A1-3. Specimen 011 Records

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106 Figure A1-4. Specimen 019D Records

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107 Figure A1-5. Specimen 020B Records

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108 Figure A1-6. Specimen 022 Records

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109 Figure A1-7. Specimen 025 Records

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110 Figure A1-8. Specimen 032 Records

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111 Figure A1-9. Specimen 043 Records

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112 Specimen 048 Figure A1-10. Specimen 048 Records

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113 Figure A1-11. Specimen 049 Records

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114 Figure A1-12. Specimen 054 Records

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115 Figure A1-13. Specimen 064 Records

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116 Figure A1-14. Specimen 067 Records

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117 Figure A1-15. Specimen 070 Records

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118 Figure A1-16. Specimen 073 Records

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119 LIST OF REFERENCES [1] NCDC. Billion Dollar Climate and Weather Disasters, 19802008. National Climatic Data Center (NCDC) 2008 [2] Insurance Services Office (ISO), 545 Wa shington Boulevard, Jersey City, NJ 07310 [3] Pielke RA, Landsea CW. Normalized Hurric ane Damage in the United States: 1900-2005. Natural Hazards Review 2007. 9 (1); 621-631. [4] Blake ES, Rappaport EN, Landsea CW. NWS TPC-5 The Deadliest, Costliest, and Most Intense United States Tropical Cyclones from 1851 to 2006 (and other frequently requested hurricane facts). National Weather Service; 2007. [5a] US Census Bureau. Interim Projections of the Total Population for the United States and States: April 1, 2000 to July 1, 2030. US Census Bureau; 2008. [5b] US Census Bureau. Cumulative Estimates of Resident Population Change for the United States, Regions, States, and Puerto Rico and Region and State Ranki ngs: April 1, 2000 to July 1, 2008. US Census Bureau; 2008. [6] Hartwig RP. Florida Property Insurance Facts. III Institute fo r Insurance Information; 2008. [7] Hartwig RP. Florida Case St udy: Economic Impacts of Business Closures in Hurricane Prone Areas. III Institute for Insurance Information; 2002. [8] Executive Order 92-291. Governors Comm ission on Hurricane Andrew, Executive order 92291. Governors Disaster Planning an d Response Review Committee; 1992. [9] FEMA. Building Performance: Hurricane Andrew in Florida. Federal Emergency Management Agency; 1992. [10] FEMA. Summary Report on Building Perf ormance: 2004 Hurricanes. Federal Emergency Management Agency; 2005 [11] NCDC. Climate of 2004 Atlantic Hurricane Season. National Climatic Data Center (NCDC); 2004. [12] NCDC. Climate of 2005 Atlantic Hurricane Season. National Climatic Data Center (NCDC); 2005. [13] Katsaros JD, Hardman BG. Failed Fenestra tion: New Materials Require New Techniques. In: Thermal Performance of the Exterior E nvelopes of Whole Buildings X International Conference Proceedings, ASHRAE; 2007. [14] Simpson RH. The Hurricane Disaster Pote ntial Scale. Weatherw ise, 1974; 27: 169-186. [15] NOAA. Data for hurricane charts gathered from:

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120 http://csc-s-maps-q.csc.no aa.gov/hurricanes/viewer.html National Oceanographic and Atmospheric Associatio n; Accessed 7-12-2008. [16] Sparks PR, Schiff SD, Rei nhold TA. Wind Damage to Envel opes of houses and Consequent Insurance Losses. Journal Wind Engineering an d Industrial Aerodynamics, 1994; 53 (1-2): 145155. [17] Gurley K, Burton J, Abdullah M, Masters F, Reinhold T. Post 2004 Hurricane Field Surveyan Evaluation of the Relative Performance of the Standard Building Code and the Florida Building Code. Department of Civil and Coas tal Engineering, College of Engineering, University of Florida, Structures Research Communication No. 53102-2, 2006. [18] Blocken B, Carmeliet J. Spatial and Tempor al Distribution of Driving Rain On A Low-Rise Building. Wind and Struct ures, 2002; 5(5): 441-462. [19] Blocken B, Carmeliet J. A Review of Wind-Driven Rain Research in Building Science. Journal of Wind Engineer ing and Industrial Aerodynamics, 2004; 92: 1079. [20] Best AC. The Size Distributi on of Raindrops. Quart. J. R oy. Meteorological Society, 1950; 76 (327): 16-36. [21] Mualem Y, Assouline S. Mathematical Model for Rain Drop Distribution and Rainfall Kinetic Energy. Trans. Amer. Soc. Agric. Eng, 1986; 29 (2): 494-500. [22] Karagiozis A, Hadjisophocleous G, Cao S. Wind Driven Rain Distributions on Two Buildings. Journal of Wind Engineering and I ndustrial Aerodynamics 1997; 67(8): 559-572. [23] Choi ECC. Simulation of Wind Driven Rain Around the Building. Journal of Wind Engineering and Industrial Ae rodynamics, 1993; 46-47: 721-729. [24] Choi ECC. Parameters Aff ecting the Intensity of Wind Driven Rain on the Front Face of a Building. Journal of Wind Engineering and Industrial Aerodynami cs, 1994; 53(1-2): 1-17. [25] Choi ECC. Determination of Wind Driven Rain Intensity on Building Faces. Journal of Wind Engineering and Industrial Aerodynamics, 1994; 51(1): 55-69. [26] Choi ECC. Wind Driven Ra in on Building Faces and the Driving Rain Index. Journal of Wind Engineering and Industrial Aerodynamics, 1999; 79(1-2): 105-122. [27] Rodgers GG, Poots G, Page JK, Pickeri ng WM. Theoretical Predictions of Rain Drop Impactions on a Slab Type Building. Building Science, 1974; 9: 181-190. [28] Mualem Y, Assouline S. Mathematical Model for rain Drop Distrubution an Rainfall Kinetic Energy. Transactions of the Ameri can Society of Agricultural Engineering ASAE TAAEAJ, 1986; 29(2): 494-500. [29] Blackall TN, Baker MC. Ra in Leakage of Residential Wi ndows in the Lower Mainland of British Columbia. Division of Building Research National Research Council of Canada; 1984.

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121 [30] Mullens M, Hoekstra B, Nahmens I, Martin ez F. Water Intrusion in Central Florida Homes during Hurricane Jeanne in September 2004. Report to U.S. DOE, University of Central Florida Housing Constructability Lab; 2006. [31] J.W. Lstiburek. Rainwater Management Pe rformance of Newly C onstructed Residential Building Enclosures During August and Septem ber 2004. Prepared for the Home Builders Association of Metro Orlando and the Fl orida Home Builders Association; 2004. [32] RDH. Water Penetration Re sistance of WindowsStudy of Codes, Standards, Testing, and Certification. RDH Building Engineering Limited; 2002. [33] RDH. Water Penetrati on Resistance of Windows Study of Manufacturing, Building Design, Installation and Maintenance Factors. RDH Building Engineering Limited; 2002. [34] Hershfield DM. Technical Paper No.40Rainfall Frequenc y Atlas of the United States. National Weather Service; 1961. [35] NOAA. NOAA Technical Memorandum NWS Hydro-35. National Oceanic and Atmospheric Admini stration (NOAA); 1977 [36] Tokay A, Bashor PG, Habib E, Kasparis T. Raindrop Size Distribu tion Measurements in Tropical Cyclones. American Meteorological So cietyMonthly Weather Review, 2008; 136(5): 1669-1684. [37] Willis PT, Tattelman P. Drop-Size Distribution Associated With Intense Rainfall. Journal of Applied Meteorology, 1989; 28: 3-15. [38] AAMA/WDMA/CSA 101/I.S.2/ A440-05. Standard specifi cation for windows, doors and unit skylights. American Architectural Ma nufacturers Association/ Window and Door Manufacturers Association/ Canadi an Standards Association; 2005. [39] AAMA 501.1-05. Standard test method for exterior windows, curtain walls, and doors for water penetration using dynamic pressure. Illino is, USA: American Arch itectural Manufacturers Association; 2005. [40] AAMA 520 (Draft). Voluntary sp ecification for rating the severe wind driven rain resistance of windows doors and unit skylights. Illinois, USA: American Architectural Manufacturers Association; 2005. [41] ASTM E331-00. Standard Test Method for Water Penetr ation of Exterior Windows, Skylights, Doors, and Curtain Walls by Uniform Static Air Pressure Difference. Pennsylvania, USA: American Society for Testing and Materials; 2000. [42] ASTM E547-00. Standard Test Method for Water Penetr ation of Exterior Windows, Skylights, Doors, and Curtain Walls by Cyclic Static Air Pressure Difference. Pennsylvania, USA: American Society for Testing and Materials; 2000.

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122 [43] ASTM E1105-05. Standard Test Method for Field Determination of Water Penetration of Installed Exterior Windows, Skylights, Doors an d Curtain Walls Uniform or Cyclic Static Air Pressure. Pennsylvania, USA: American Society for Testing and Materials; 2005. [44] ASTM E2268-04. Standard Test Method fo r Water Penetration of Exterior Windows, Skylights and Doors by Rapid Pulsed Air Pressu re Difference. Pennsylvania, USA: American Society for Testing a nd Materials; 2004. [45] AS/NZS 4284:1995. Testing of Building Faades. Homebush, Australia: Australia Standards; 1995. [46] JIS A 1517. Test Method of Water Tightness for Windows and Doors. Tokyo, Japan: Japan Standards Association; 1984. [47] TAS 202-94. Criteria for Testing Imp act & Nonimpact Resistant Building Envelope Components Using Uniform Static Air Pressure. Florida, USA: Department of Community Affairs, Florida Building Code Codes and Standards; 1994. [48] TAS 203-94. Criteria for Testing Products Subject to Cyclic Wind Pressure Loading. Florida, USA: Department of Community Affairs, Florida Build ing Code, Codes and Standards; 1994. [49] Masters FJ, Gurley KR, and Prevatt DO. Fullscale simulation of turbulent wind-driven rain effects on fenestration and wall systems. 3rd International Sympos ium on Wind Effects on Buildings and Urban Environment, Tokyo, Japan, March 4-5, 2008. [50] Lindgren O. Climate Data OS Parameters fo r The Design of an Equipment for Accelerated Ageing of Windows and Other Wood-Based Produc ts. Swedish Council for Building Research, 1984; 1: 195-199. [51] Gjelsvik T. Apparatus fo r Accelerated Weathering of Build ing Materials and Components. Materials and Structur es, 1983; 16(3): 209-211. [52] Fazio P, Athienitis A, Marsh C, Rao J. Environmental Chamber for Investigation of Building Envelope Performance. Journal of Ar chitectural Engineering, 1997; 3(2): 97-102. [53] Salzano CT. Residential Window Installation Options for Hurricane-Prone Regions. Masters thesis presented to The University of Florida, 2009.

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123 BIOGRAPHICAL SKETCH Carlos Rodolfo Lopez was born in Bogota, Colo mbia. At the age of 5 he moved the state of Florida where he grew up. As the only child of a Business Administrator and Architect/Contractor he was exposed to the cons truction environment at a very young age. Upon graduating from John I. Leonard High School in June 2003 he bega n his pursuit of a Bachelor of Science degree in civil engineering, with a focus in Structures, from the University of Florida. While completing his B.S. he had the privilege of meeting great profession als from his field who shared his interests and passions. Upon co mpletion of his degree in 2007 he sought the mentorship from one such professional, Dr. Forrest J. Masters. Under his mentorship he studied the behavior of building assemblies subjected to hurricane force wind and rain. In his study of building science he had the great opportunity of working side by side with professionals ranging from top executives of some the largest fenestra tion manufacturing companie s to heads of the top trade organizations and leading legislative officials. While completing his requirements for his Master of Engineering degr ee, Carlos also had the privilege participating in the Florida Coas tal Monitoring Program (FCMP). The FCMP is a unique joint venture focusing on full-scale experimental met hods that quantify low level hurricane wind behavior and the resultant loads on re sidential structures. As a team leader of the FCMP Carlos deployed to Hurricane s Gustav in Louisiana, Ike in Texas, and Tropical Storm Fay in Central Florida to set up instrumentation that quantified near surface hurricane behavior. Upon passing of the storms, Carlos also participated in teams th at performed post-storm damage assessments. Once fulfilling all requirements required for the Master of Engineering degree, Carlos will pursue a Doctor of Philosophy degree in civil engineering from the Univ ersity of Florida.

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124 Carlos R. Lopez is a student member of the American Association for Wind Engineering, the American Society of Civil Engineer s, and American Concrete Institute.