Solution that will allow me to spray foam sloped part of roof and dormer roof mid-construction
Climate zone 7 Canadian Prairie unvented unconditioned attic cape cod style house, 1940s
I want to have the sloped portion of the roof spray foamed prior to winter. The problem I’m having is figuring out a way to have the work done knowing that in the spring portions of my roof sheathing will be removed to lay plywood (I’m having eave extensions added – approx. 3 feet of existing roof sheathing will be removed around perimeter and to allow for plywood tie in).
Can you think of what I can insert on the underside of the room sheathing that will allow them to spray foam? I’m only having 3″ of spray foam as rafters are only 2×4 fir. While inadequate, I am not replacing them.
Thanks.
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Replies
Mill,
You can install rectangular strips of asphalt felt or cardboard in each rafter bay, covering the underside of the roof sheathing before the spray foam contractor shows up. That's labor-intensive work, but it will prevent the spray foam from gluing everything together.