Corrugated Foam Vent Channels and Spray Foam
pv13
| Posted in GBA Pro Help on
Contractors have historically challenged venting spray foam roof assembles in our area of Ontario Canada climate zone 6
Wondering whether anyone has had success using applied vent channels to backside of roof sheathing prior to spray foam for continuous venting.
Big box distributers tend to only stock plastic or foam vent channels My understanding is plastic would decouple from spray foam so maybe foam is feasible. I am concerned about the vent channels being crushed by the spray foam.
Any experience out there with this?
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https://buildingscience.com/documents/published-articles/pa-crash-course-in-roof-venting/view
2nd image, praise Joe.
Good installers can flash the baffle with a super light layer to beef it up.
Thanks Gnoll, I have seen this detail before. Vent baffle referenced in this article is plastic and we are dealing with foam mostly.
A local spray foam installer mentioned spray foam would decouple from plastics baffles and 'belly out' creating a void
Thats more concerning to me then using a foam baffle, provided it doesn't crush under the expanding pressure