Insulating a roof, FH issue 299
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As I read Josh Salinger’s article in the July issue I’m questioning the installation of the WRB on top of the roof rafters to create a 1.5″ air gap for the roof ventilation.
In my experience with dense-packed cellulose, the WRB would bulge out and probably restrict the area of the air channel, maybe with 75%.
With the roof sheeting in place before the cellulose installation, there is no way to “belly roll” the WRB to create the full air channel.
I would like this insulation system on an upcoming project but I’m not sure if I would have sufficient ventilation.
Any feedback out there?
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Replies
Anders,
You may find this related discussion interesting:
https://www.greenbuildingadvisor.com/article/building-a-vaulted-high-performance-and-foam-free-roof-assembly#comment-212741