- Product Insights
- Energy Solutions
- BuildingGreen's Top Stories
- BuildingGreen Talks LEED
It's not easy being a weather-resistive barrier (WRB): it has to stop liquid water, be tough and not tear, but also be flexible to wrap around building elements. And it often needs to be vapor-permeable to promote drying.
In the past, manufacturers could cherry-pick the standardized test to use to "qualify." That's how we ended up with industry acceptance of perforated and cross-woven housewrap that literally leaks like a sieve.
Now we have a new ASTM "Standard Specification for Vapor Permeable Flexible Sheet Water-Resistive Barriers Intended for Mechanical Attachment." This standard also aligns with the latest version of the ICC-ES Acceptable Criteria (AC) 38–"Acceptance Criteria for Water-Resistive Barriers (PDF)." The table below presents the requirements for WRBs used in the new standard and now by GreenSpec.
Here are the key points from the table.
Most high-quality, well-known spun-bonded polyolefin housewraps (such as Tyvek and Typar) comply with the new ASTM standard Type II requirements; the same is true for quality building papers (Fortifiber, for example).
You might not find explicit compliance to this new standard on a manufacturer's website; if it's not clear, ask them. Or just use a building paper or housewrap listed in GreenSpec.
Does this new standard solve all of our building-assembly problems? Not by a long shot; you still need to marry the WRB to all flashing details at penetrations and transitions. But it sure makes a lot of sense to start with the right materials as you design, spec, and build high-performance building assemblies.
What are your experiences with WRBs, and questions? Please post your comments below.
I believe the Viridian decking we installed is 15/16" thick by 2-1/2" wide; I'm not seeing those dimensions on the Viridian...
Hi there! I've been sourcing reclaimed exterior deck material for a client, and am interested to know:
The thickness of the material you...
Erica, 3-way LED bulbs are sold in stores and online. Just do a search or ask at your local hardware store.
Meredith Williams says, "Hi there! I've been sourcing reclaimed exterior deck material for a client, and am interested to know: The thickness of the material you used..." More...
Erica E. Tactical says, "Anyone know a way to replace incandescent 3-way light bulbs with LEDs? My table lamps are all 3-way and I like the ability to have ambient or..." More...
Archives by Category
AIA Convention (19) [RSS]
Authors (7) [RSS]
Awards (8) [RSS]
Behind the Scenes (44) [RSS]
Books & Media (69) [RSS]
BuildingEnergy Conference (3) [RSS]
BuildingGreen Talks LEED (53) [RSS]
BuildingGreen's Top Stories (119) [RSS]
Bulletin (7) [RSS]
Case Studies (27) [RSS]
Colleges and Universities (2) [RSS]
Energy Solutions (304) [RSS]
Events (93) [RSS]
Google Earth/Sketchup (5) [RSS]
Greenbuild '07 (27) [RSS]
Greenbuild '08 (29) [RSS]
Greenbuild '09 (14) [RSS]
Greenbuild '10 (6) [RSS]
Greenbuild '11 (6) [RSS]
LEED (51) [RSS]
Living Future (6) [RSS]
Miscellania (41) [RSS]
Nature & Nurture (70) [RSS]
Op-Ed (68) [RSS]
Passive Survivability (7) [RSS]
Politics (32) [RSS]
Product Insights (211) [RSS]
Product Talk (102) [RSS]
Q&A (9) [RSS]
Resilient Design (11) [RSS]
Riversong's Radical Reflections (12) [RSS]
Science & Tech (30) [RSS]
Sticky Business (12) [RSS]
The Industry (97) [RSS]
Water Wise Guys (12) [RSS]