3/8/2017 TESTING THAT MATTERS: WATER-RESISTIVE BARRIERS. Quick Update on WTF PSA Tape Testing. Quick Update on WTF PSA Tape Testing

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1 TESTING THAT MATTERS: WATER-RESISTIVE BARRIERS Quick Update on WTF PSA Tape Testing Quick Update on WTF PSA Tape Testing Teaming up: Umass-Amherst Building Construction Technology Program More statistically significant testing, focusing on installation conditions Adult Supervision 1

2 RDI Blind Trust for Testing? So what is next? WTF 2.0? Keep tabs on WTF on the buildinggreen.com blog 2

3 WRB R703.2 Water-resistive barrier. One layer of No. 15 asphalt felt, free from holes and breaks, complying with ASTM D226 for Type 1 felt or other approved water-resistive barrier shall be applied over studs or sheathing of all exterior walls. ASTM D226 is specification for asphaltimpregnated felt paper. WRB R Water-resistive barriers. Water-resistive barriers shall be installed as required in Section R703.2 and, where applied over wood-based sheathing, shall include two layers of a water-resistive vapor-permeable barrier. Each layer shall meet both of the following requirements: 1. A water resistance of not less than that of 60-minute Grade D paper; or a minimum hydrostatic head of 24 inches (60.9 cm) when tested in accordance with hydrostatic pressure test method AATCC ; or a minimum water transudation time of 60 minutes when tested in accordance with ASTM D A water vapor permeance of not less than that of No. 15 felt; or a minimum permeance rating of 8.5 gr/ h.ft.2 in Hg (US perm) ( kg/Pa s m2) when tested in accordance with Procedure B of ASTM E96. Exception: One layer of water-resistive barrier complying with R703.2 is permitted when a drainage space that allows bulk water that allows water to flow freely is provided. Tom Butt: Water Resistance & Vapor Permeance of WRBs Marketing and tradition appear to have played a major role in shaping perceptions of WRBs by both the public and building industry professionals. There is a critical need to develop and test building models that subject WRBs to conditions that replicate those in actual service and to develop standards that reflect actual service needs. Journal of ASTM International Dec 2005 (Vol 2 No. 10) 3

4 Weather-Resistive Barriers ASTM D779-94: the boat test: It is designed for use with materials that require a relatively short time to test (up to approximately 30 s) AATCC 127, the "hydro-head" test: 22-inch column of water leakproof for 5 hours (approximating a 200 mph wind-driven rain) The code? equivalent materials 24 different test standards may apply AATCC Hydrohead Test AATCC Hydrohead Test GreenGuard Raindrop Reemay Typar 4

5 Modified Boat Test 1. Water dish 2. Raw wood 3. Wrap/building paper 4. Blotter paper 5. plywood Fisette s Procedure 1. We cut samples of 1/2-inch bevel cedar siding into 2-inch squares and soaked them in water. Saturating the siding was an attempt to mimic what happens to untreated wood siding or wood siding that has not been backprimed when it is exposed to a period of rain. 2. Next we placed a square of saturated siding into each of 5 petrie dishes that were half-filled with water. The top half of our siding samples remained well above the water line. Water in the dishes served to charge our samples, maintaining saturation throughout the test period. 3. Next, we placed a 4-inch square of housewrap over each piece of saturated siding so that its edges extended well beyond the perimeter of the dish. On top each square of housewrap we positioned a 2-inch diameter disk of blotter paper. The blotter served as a visual indicator to tell us if any water leaked through the housewrap. 4. Finally, a 2-inch square piece of 1/2-inch plywood was placed on top of the blotter paper. The entire sandwich was held together firmly with an elastic band. The sandwiches were unbanded and checked every 2-hours for 2 days (9:00 am - 5:00 pm --- no checking at night). Our Procedure Pick a WRB Do boat test Do hydrohead test Do modified boat test Fisette procedure Think through and apply: What do you want your WRB to do? What is the best way/what are the best ways to test what you want your WRB to do? 5

6 Generally, asphalt impregnated do well Housewraps tend to not boat test, do with hydrohead test Tests need to provide useful information for the application Two things to do (code): breathe & resist water Don t let liquid molecules through, let vapor through Resist bulk water, asphalt Boat into water, surface material turns into vapor, never have isolated movement of heat Housewrap fail in boat test, good at resistence to high pressure Raindrop (1): reverse directions, tested both sides, water went through when wrap was reversed (installed backwards) Raindrop (2): boat test passed, if there wasn t a weave, the paper wouldn t pass vapor barrier, cross woven allows vapor to pass If tests are designed to measure properties that aren t needed in your material, then why are we doing the test? Zip wall: water ponding test - no tape lines in test area, test only at weather-resistive barrier surface Zip wall tape: tape test for the taped strips, test vertically as well not flat, similar to installation method Zip wall vertically: test how water trickles down the face Different products and manufacturers cannot compare different products and their differing attributes Tape test on leading edges of taped lines; wind tests on differing applications Need to work more on field-service tests, which predict what is happening in the field, on your job sites. Ought to be doing mock-ups with wall penetrations: electrical, window, venting; then wet as weather would act upon surfaces 10 x10 wall surface; each manufacturer should be testing their product on the similar wall system Would Air Barrier products approve the differing wall test? Different penetrations require varying installation techniques that would be required for tests to pass. Skylights: comes with flashing kit Liquid flashings partnering with systems, product integration, marketing strategy More Wingnut Testing out there Spend more money! A method to dimple the pipe test either a dimple up or out. 6

7 SECTION R102 ALTERNATIVE MATERIALS, DESIGN AND METHODS OF CONSTRUCTION AND EQUIPMENT R102.1 General. The provisions of this code are not intended to prevent the installation of any material or to prohibit any design or method of construction not specifically prescribed by this code, provided that any such alternative has been approved. The code official shall be permitted to approve an alternative material, design or method of construction where the code official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, purpose intended, at least the equivalent of that prescribed in this code. Water Penetration Testing of Assemblies ASTM E1105: Field Determination of Water Penetration of Installed Exterior Windows, Curtain Walls and Doors by Uniform Static Air Pressure Difference Outlines the test method for the field determination of water penetration of installed exterior windows, curtain walls and doors. 7

8 Water Penetration Testing of Assemblies AAMA 502: Voluntary Specification for Field Testing of Windows and Sliding Glass Doors - Primarily outlines field performance requirements for resistance to water penetration and air leakage resistance for windows and glass doors (United States). AAMA 503: Voluntary Specification for Field Testing of Storefronts, Curtain Walls and Sloped Glazing Systems - Primarily outlines field performance requirements for resistance to water penetration and air leakage resistance for Storefronts, Curtain Walls and Sloped Glazing Systems (United States). CAN/CSA-A440.4 (appendix D): Field Testing of Window and door Installations - Primarily outlines field performance requirements for resistance to water penetration and air leakage resistance for windows and doors (Canada). 8