I am remodeling my basement and planning on using closed-cell spray foam
schverigs
| Posted in Energy Efficiency and Durability on
I am remodeling my basement and planning on using closed-cell spray foam. I am also doing an earthquake retrofit. When/how should I install the spray foam?
I have a cripple wall and am required to install plywood to create a shear wall. My question is when/how should I install the spray foam? Should I spray before I install the plywood? Or after? Or both? My concern with spraying before is that the plywood needs to be nailed directly to the studs/bottom plate/top plate in the cripple wall so these can’t be spray foamed so I am afraid this leaves a thermal bridge.
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Replies
Lars,
You need to coordinate the work between the two subcontractors who will be working in your basement. Call up your spray foam contractor and your earthquake-retrofit contractor and explain the situation to both of them. You should suggest that they communicate with each other and coordinate their work.
Hi Martin,
I will make sure we coordinate the work. I am unsure though what the order should be. Spray foam first and than install the sheer wall (plywood on cripple). Will this leave a thermal bridge (top/bottom plate/studs) where the plywood connects to the cripple wall?
Thank you
Lars,
If your cripple wall is a stud wall that will be enclosed with plywood or OSB on both sides, then your studs and plates will, indeed, be thermal bridges. The best way to interrupt the thermal bridging is with a continuous layer of rigid foam.
If you decide the go this route, you would need to cover the rigid foam with siding (if you put it on the exterior side) or with gypsum wallboard (if you decide to put it on the interior side).