Today s Trends in Air Barriers. Building Envelopes Today

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1 Today s Trends in Air Barriers Fred Kramer, Building Envelope Solutions Team Marcy Tyler, Technical Applications Manager Building Envelopes Today A conservative estimate of building envelope failure is 3-5% N.A. building envelope repair is a multi-billion dollar industry. Most problems are moisture-related, caused by air or moisture leakage. Most façade problems relate to terminations and connection details. 70% of all construction litigation is related to façade leakage Tremco Inc. 1

2 What Causes Building Envelope Failure? 90% of the time, it comes down to the transitions and terminations Af failure in one component can and ddoes affect other components in the building 2008 Tremco Inc. The Evolution & Building Science Of Air Barriers 2

3 Premature Deterioration Of s Led To Adoption Of Air Barrier Codes Northern Climates Were Prone To Greater Deterioration 3

4 The Uncontrolled Escape Of Warm Interior Air To The Exterior Was The Issue Lack Of Continuity Of The Envelope Played The Major Role In The Damage 4

5 Window, Roof, Soffit Intersects All Proved To Be Trouble Areas Older Buildings May Not Have Leaked Water, But They Leaked Air! 5

6 In Some Cases Severe Air Leakage lead to Complete Re-Cladding Past Building Practices Focused More On Water Shed Versus Continuous Air Seal 6

7 Energy Loss And Wall Damage Were Caused By Air Leakage Poor Quality Mortar Joints Added To The Outbound Air Flow 7

8 Assembly Transitions Lacked Durable Air Seals Seals Were Not Made Around Penetrations 8

9 Excess Mortar Prevented Drainage Of The Cavity Wall Evolution Of The Air Barrier These Older, Deficient Building Practices And A Federal Mandates For Energy Efficient Buildings.. Various Energy Acts 2005 to 2009 Created A Demand For Air Barriers. 9

10 NIST Study Confirmed That A Continuous Environmental Separation Interior To Exterior Provided a 5 To 8 Year Payback In Energy Savings! Air Barriers Started Out As. THE WILD, WILD WEST! WITH MUCH CONFUSION, THERE WAS A STAMPEDE BY MANUFACTURERS TO GET PRODUCTS TO MARKET! 10

11 A Multitude Of Air Barrier Products Air Barrier Evolution Canada NABA-1995 ABAA Air Barrier of America Association Nov/2000. MA Energy Code July 2001 WI 2002 MI RI GA MN FL Under consideration: NY, NC, SC, IL. 11

12 Air Barrier Evolution Standards Testing Protocols Air Barrier Guide Specifications Developed Air Barrier Evolution Membership Technical Committee Education and Outreach Committee House wrap Committee NEW Transition Materials Committee Industry initiatives 12

13 ABAA Membership Growth 2009: : Membership Numbers

14 Growth Of ABAA Approved Contractors 130 Approved Contractors In Approved Contractors In Approved Contractors Approved Contractors Statistics On QAP Participation - Training 14

15 Statistics On ABAA Specified Projects ABAA Specified Projects 2009: : ABAA Specified Projects THE WILD, WILD WEST IS BEING SETTLED! 15

16 Regional Differences In Construction May Cause Confusion Some Current, Regional Practices Are Not Best Practice. Best Practice Calls For The Containment And Conditioning Of The Inside Air. Only Insulating Between Studs Is Not A Best Practice. 16

17 Best Practice The Perfect Wall Insight The Perfect Wall By Joseph W. Lstiburek, Ph.D., P.Eng., Fellow ASHRAE Cladding Bulk water Control Layers Insulation Air & Vapor Structure Climate Zones 17

18 ASHRAE - Vapor Drive Zones NorthernCold Clim ate - Vapor Drive Interior to Exterior Moderate Climate - Vapor Drive Equal Both Directions Hot/Humid Climate - Vapor Drive Exterior to Interior ASHRAE American Society of Heating, Refrigerating, and Air-Conditioning Engineers Class I Vapor Barrier 0.1 perm or less Class II Vapor Barrier 1.0 perm or less and greater than 0.1 perm Class III Vapor Barrier 10 perm or less and greater than 1.0 perm ASTM E 96 Test Method A (Desiccant method or dry cup method) Vapor impermeable 0.1 perm or less Vapor semi-impermeable 1.0 perm or less and greater than 0.1 perm Vapor semi-permeable 10 perm or less and greater than 1.0 perm Vapor permeable Greater than 10 perm Proposed classifications by Joseph Lstiburek, Ph.D., P.Eng. - Building Science Corporation 18

19 Air Barriers Can Be: CONFUSING! Vapor Permeable (Air Barrier) Non-Vapor Permeable (Air & Vapor Barrier) Insulation (providing air, vapor and thermal protection) Spray Applied Polyurethane Foam 19

20 Fluid Applied Air Barrier Membranes Sheet Applied Peel N Stick 20

21 Which Is More Effective In Controlling Moisture? Controlling moisture transport via air flow? HINT! Or Controlling vapor diffusion? WHY? Moisture Movement Above Ground Diffusion vs. Air Leakage Source: Building Science Corporation Builders Guide The movement of moisture into a building through the wall assembly above grade can take two main forms. The first is the slow transmission of water vapor through vapor diffusion, driven by pressure and temperature differentials. The second is the more sever movement of moisture-laden air through porous building materials, holes and/or penetrations in the building envelope. Addressing moisture movement above grade by Addressing moisture movement above grade by air is the most significant vehicle in eliminating moisture in the wall. Moisture movement by air accounts for 70-90% of the moisture, while the remaining 10-30% is moved by vapor diffusion. 21

22 Air Barrier Continuity Should Be Across The Entire Envelope Air Barriers Must Be Continuous 22

23 What Has The Industry Done To Insure Continuity? The evolution of industry test standards Air Barrier Evolution Testing of Air Barrier Materials MATERIAL must have an air permeance of less lb/ft2 23

24 ASTM E Air Permeance Very Relevant To CMU CMU Leaks Air Like A Sieve! Air Barrier Evolution Next Logical Step Forward Test Assemblies vs. Component Materials ASTM E Standard Test Method for Determining Air Leakage of Air Barrier Assemblies 24

25 Air Barrier Evolution ASTM E 2357 Air Leakage of Air Barrier ASSEMBLIES ASTM E 331 Water Leakage Air Barrier Evolution ASTM E 2357 Air Leakage of Air Barrier ASSEMBLIES ASTM E 331 Water Leakage 25

26 Air Barrier Evolution D1970 (8.9) Self Sealability (Head of water test) Air Barrier Evolution Surface Burning Characteristics of Building Materials NFPA Codes Healthcare Construction Asphaltic-based materials will struggle Photo courtesy of Omega Point Laboratories 26

27 Air Barrier Evolution ASTM E84 Provides Surface Flame Spread & Smoke Density Photo courtesy of Omega Point Laboratories Air Barrier Evolution NFPA Evaluation of Fire Propagation Characteristics of Exterior Non-Load-Bearing Wall Assemblies Containing Combustible Components Schematic NFPA Photo courtesy of Dow Chemical White Paper November

28 Air Barrier Evolution Architects and specifiers recognize the importance of an effective air barrier for a building s energy efficiency, health and durability. ABAA requires this testing as part of the product approval process. ASTM E2357 is a useful tool in testing and evaluating the performance of proposed air barrier assemblies under real-world conditions. ALMOST REAL-WORLD! Air Barrier Evolution We have put the Air Barrier Opaque wall surface under a microscope. Extremely low permeance requirements have been established 28

29 The Opaque Wall Is Easy To Address AIR BARRIERS WHAT IS THE. What they don t want you to know! What they don t want you to know! What they don t want you to know! What they don t want you to know! 29

30 The Dirty Little Secret Is - Most air leakage failures aren t going to occur through the opaque wall. Gypsum Board doesn t leak a lot of air to begin with. CMU when treated, isn t going to leak an appreciable amount of air. YOU CAN STILL HAVE A MAJOR AIR BARRIER FAILURE! WHY? It is not about the WALL! IT is about how DISSIMILAR OPAQUE COMPONENTS WALL come together! TO WINDOW / CURTAINWALL CONNECTIONS THE WEAKEST LINK! 30

31 Focus On The Opaque Wall Is Not Enough What about: Deflection joints? Window/curtain-wall connections? Seismic requirements? Wall have three dimensional returns? Continuity of the roof/wall intersect? What products/components/assemblies make these critical connections? Can connections be made in the right sequence? Proper details? Tested Assemblies? Durability Of Connection Points Of Are All Impacted By: Wind Drift Deflection Creep Thermal Movement Moisture Expansion Tolerances How Long Will The Connections Last? 31

32 Wind Drift Is Not One Directional In Nature Courtesy of Karol Kazmierczak, The Construction Specifier, Oct., 2008 Wind Drift Can Be As Much As 4 On A 10 Story Building 32

33 Envelope Performance Are the seals at connection points durable? Will they stand repeated pressurized cycling? Will they withstand major wind events without damage? How well will they withstand changes in live load, wind drift, creep, settlement and thermal stress? Plywood Does Not Equal Real World Test Mock-up ASTM E2357 Where should the focus be to deliver an effective REAL-WORLD Air Barrier? 33

34 The Typical Options For Attachment Of Air Barrier To Other Cladding Components? Sealants (Typically the primary connection method) Self-Adhered Membranes (S-A-M) Spray-Polyurethane Foams Cured and Uncured Rubber Products Silicone Sheet Products Others? TYPICAL SEALANT CONNECTION TO AN AIR BARRIER MATERIAL 34

35 Sealant Limitations For Envelope Connections Limited by a maximum and minimum operable joint size. Limited by the amount of movement at the connection points. Limited by possible lack of compatibility with rubberized asphalt membrane or other sealants. Limited by another dirty little secret! THE DIRTY LITTLE SECRET? Many sealants do not adhere to the polyethylene backing layer of many self-adhered membranes! 35

36 Sealant Limitations For Envelope Connections: Understanding performance on the polyethylene film of SAM is critical: Polyethylene is a natural bond breaker for sealants. Compatibility has two different meanings! Sealants and Polyethylene l are typically compatible. (They do not have an adverse effect on one another.) But many sealants do not adhere to polyethylene. There is variability in the composition of polyethylene. 36

37 Best Adhesion Sealant Limitations For Envelope Connections: 37

38 Sealant Limitations For Envelope Connections: The industry has left a void as to how critical connections are made: Termination mastic and LM products are not sealants. AB Manufacturers have typically pushed off issue to sealant manufacturers. Poor Adhesion By others further clouds the issue. 38

39 Sealant Limitations For Envelope Connections: ABAA suggests - Single Source is BEST. Why is this important? If you leave it to chance - then it is likely you will not get the best combination of products! Sealant Limitations For Envelope Connections: OKAY! But remember, sticking to polyethylene is only the first hurdle: Other issues also impact sealant performance. Other issues limit their use. 39

40 Sealant Limitations For Envelope Connections Are you relying on the perfect ¼ to ½ inch bead of sealant to make the all the critical connections? Air barrier connections are not the perfect shape! The perfect hour glass shape. Sealants May Not Effective For Spanning Larger Gaps A two inch wide exterior sealant joint viewed from the interior. 40

41 Sealant Limitations For Envelope Connections Exterior Cosmetic Seal Primary sealant line must traverse across mill finish closure plate and shop applied silicone sealant. Sealant Limitations For Envelope Connections Primary (inside) seal was installed from the exterior. Intimate contact could not be made with the substrates or backer rod. Viewed from interior side after removal of backer rod. 41

42 Sealant Limitations For Envelope Connections -High Stress Joints Air Temperature Surface Temperature Rapid thermal expansion can make sealant installation an impossibility. Sealant Limitations For Envelope Connections - High Stress Joints Corners A very high stress area with multi-directional movement. 42

43 Self-adhering Membranes (SAM) Spin offs of below grade waterproofing technology. Designed to be fulladhered to: Structural Smooth surfaces Accommodate 1/16 of crack movement Bridge ¼ gap ONLY Limitations Of Self-adhering Air Barrier Membranes 1 to 1 1/4 All membrane manufacturers have stated that SAM should not bridge over gaps, voids ¼to½ in width unsupported 43

44 SELF ADHERED MEMBRANES ARE NOT INTENDED TO SPAN UNSUPPORTED GAPS Manufacturers Typically Require A 3 Lap A Misuse Of The Products Lack of seal at attachment point with minimal surface area. Dissimilar movement rates caused fish mouths. 44

45 Self-adhering AB Membranes Must Be Held Back From The Exterior Plane Of Facade Hmmm... Who s sealant is this? Who s membrane is this? Who s responsible when it leaks? Pathways for air & water leaks. Self Adhered Membranes Are Not Intended For Origami Tie-Ins As value engineered 45

46 Silicone Sealant Precludes The Use Of A Self Adhered Membrane As A Connection Compatible? Asphaltic Mastic 4 Sided Structural Glazing Structural Silicone Air Barrier Membranes As An Unsupported Connection May Shed Water, But They Will Leak Air. Should Only Be Used For Their Intended Purpose. Do Not Have The Lateral Movement Capability Required For A Durable Seal. 46

47 Polyurethane Spray Foam Air Barrier Polyurethane Foam Limitations For Envelope Connections Drying Shrinkage 47

48 Polyurethane Foam Limitations For Envelope Connections Cracks in foam due to movement of pre-cast panels. Polyurethane Foam Limitations For Envelope Connections Spray Foam does not prevent water infiltration. 48

49 Polyurethane Foam Limitations For Envelope Connections Typically y Foam Systems will utilize SAM by other manufacturers. Polyurethane Foam Limitations If foam is to be primary AB Seal ask: What Testing Has Been Done (ASTM 2357)? Chemical and Adhesive Properties? Long-term drying shrinkage? Dynamic Movement Capability Weather Limitations For Installation? Weather Limitations For Installation? Compatibility With Other AB Seals? 49

50 The Evolution Of Engineered Transition Assemblies How Do You Handle Special Transitions?

51 Note That Curtain-wall Race Was Milled Off To Maintain Continuity Custom Extruded Silicone Sheet Adhered With Low Modulus Silicone Sealant 51

52 This Condition Lead To The Development Of Pre-molded Silicone Corners Evolution/Developments In Tested Silicone Sheet Transition Assemblies: Ribbed design improved sealant adhesion layer. Thinner silicone sheet for greater visual oversite and workability. Adapter bar for attachment to various custom assemblies. Three basic design options. Pre-Molded corners to eliminate seamed overlaps that are prone to pull apart. 52

53 Silicone Engineered Transition Assemblies Evolution Of Translucent, Low Modulus, Silicone Sheet - Engineered Transition Assembly 53

54 Engineered Transition Mock-up Assembly Mounted In Test Chamber Engineered Transition Assembly Test Procedure: 1. Install specimen into chamber 2. Air leakage test ASTM E Static water penetration test ASTM E Dynamic water penetration test ASTM 115 mph for 15 min. 5. Structural testing ASTM E 100 psf 6. Rack system 2 (three cycles) AAMA (Modified) 7. Repeat air infiltration ASTM E Repeat static water penetration test ASTM E Repeat dynamic water penetration test ASTM 115 mph 10. Repeat structural testing to destruction ASTM E

55 Racking Wall System 2 Inches 3 Cycles Assembly Racked 2 Inches 3 Cycles AAMA (Modified) No Failures! 55

56 ASTM E PSF Load. Repeated After Racking, Air, Static & Dynamic Water Children s Hospital Of Wisconsin West Bed Tower - Wauwatosa, Wisconsin Shepley Bulfinch Richardson and Abbott Oscar J. Boldt Construction Trainor Glass / Fulton Window 56

57 Children s Hospital Of Wisconsin Self-Adhered Membrane to be covered with Metal panels Children s Hospital Of Wisconsin Head Condition Jamb Condition 57

58 Children s Hospital of Wisconsin MOCK-UP AT ATI LABS, YORK, PA. Engineered Transition Assembly Curtainwall To Adjoining Air Barrier Assembly. Children s Hospital Of Wisconsin Head Connection 58

59 Children s Hospital Of Wisconsin Continuous spans of 100 without seams in ETA membrane. Children s Hospital Of Wisconsin 59

60 University Of Chicago Residence Hall, Dining Facility University Of Chicago Residence Hall, Dining Facility Deflection Joint Installation 60

61 University Of Chicago, Residence Hall, Dining Facility Treatment Of Deflection Joint THE WRONG WAY! THE WRONG WAY! Deflection joint mock-up THE CORRECT WAY Engineered Assembly Wall To Floor Isolation Seal 61

62 Sherman Hospital Replacement Campus Elgin, IL Shepley Bulfinch Richardson and Abbott Walsh Construction Contract Glaziers Inc. Fulton Windows Sherman Hospital Replacement Campus Roller Application Of Air Barrier Material 62

63 Sherman Hospital Replacement Campus Six Story Curtain-walls Attached To Adjoining Air Barrier With An Engineered Transition Assembly Silicone Transition Strip Pre-mounted To Curtain-wall Opening 63

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68 Wisconsin Institute For Discovery And Innovation Air Barrier With Rain-Screen Design Ballenger Arch & Uhlein Wilson Arch, WJE Wall Consultant Findorff-Mortenson CM Joint Venture Wisconsin Institute For Discovery And Innovation 68

69 Wisconsin Institute For Discovery And Innovation Wisconsin Institute For Discovery And Innovation 69

70 Wisconsin Institute For Discovery And Innovation Wisconsin Institute For Discovery And Innovation 70

71 Wisconsin Institute For Discovery And Innovation ASTM E1183 Smoke test verifies continuity of Air Barrier & Window Assembly. Wisconsin Institute For Discovery And Innovation 71

72 Remember The End Game: The Intent Is to Build Durable, Sustainable Building Enclosures. Summary - A Durable Enclosure Requires Communication Design Review Mockups Training Third Party Testing Complete Specifications A Team Approach 72

73 Integrated Building Solutions Connectivity: It s not about the OPAQUE WALL. It is about how wall, window, panels, components below grade, & roof come together! It is about addressing issues like sequence of installation and compatibility. It is about recognizing the need for durable, connective seals, not just seals that pass the mock-up! Air Barrier to Window/Curtain Wall Connections Many Choices Understand Issues Compatible products Proper connectivity Cover yourself with good specifications Work with manufacturers who understand the Work with manufacturers who understand the issues 73

74 Fred Kramer, Building Envelope Solutions Team, Marcy Tyler, Technical Applications Group Manager, age e c 74