Framing over 1 inch rigid exterior insulation
OronoWoodworks
| Posted in General Questions on
We need to add some false rake overhangs and eave overhangs and I’m trying to find out if we can install 1 inch rigid foam first and then frame on top as it’s our air and water barrier. We are using silverboard HD XS 35psi on the exterior.
Our rake overhang is 12″ and our eaves are 24″
I’ve attached 2 pictures of the rake overhangs, those would then be connected all the way along the back of the building.
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Replies
Looks like most states allow deck ledgers over 1 inch foam, so maybe this isn't an absurd question, but I'm in Ontario...
I would worry about the false overhangs sagging over time, compressing the foam. Just a few solid blocks behind it would solve that problem, and you could tape over the blocks.
Yes, I agree with you, I just thought maybe it was done a lot and I was unaware. I'll add two layers blocks of 1/2" ply so I can tape over them flush with the insulation. Think I need to go 16" or would 24" spacing suffice?
OronoWoodworks,
I'd put them over the underlying studs so you get good backing.
Makes perfect sense
32" oc would probably be enough, if your studs are 16" oc.
That's good info...I'd obviously like to keep as much continuous insulation as possible. Thanks!