Insulation in boxsil
Emel
| Posted in General Questions on
update: Our trusses will be recessed by way of a inner ledge formed into the stem wall.
Our contractor has quoted Rockwool for our wall insulation with the exception of the boxsil being spray foam. We would like to avoid spray foam. Would it work to also spec rock wool for the boxsil?
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Replies
Emil,
What is a boxsil? It must be a regional term.
Inside the sill band Malcolm, between the joists. You can use any insulation as long as you seal any of the corners all the way around. Usually we use rectangles of EPS and inject foam or use a good caulk.
PK
These are recessed trusses. The foundation wall has an inner ledge the trusses will drop down into. I’m sorry, I should have mentioned that. Would we still need to seal around the corners as you said?
Only if the sill band which is keeping the joists/trusses vertical is exposed to the exterior. If the tops are behind the foundation wall, then sealing the seam at floor level is all that is needed. YOu just want to make sure all the "boxes" are airtight so the insulation doesn't have air moving through it. Would help to have a drawing.
PK