Will spray foaming my basement rot my sill plate?
Hi Martin or whoever would like to add input to my query. I live in Eastern Canada near the coast in a Zone 6/7 environment. I live in an old house with an low ceiling unfinished basement that is freezing cold all winter.
I was 100% ready to proceed with spray foaming this year however a little bit of lookin around online has me somewhat concerned. My sill plate sit directly on the concrete, a 10×10 timber, quite weathered, water damaged on the exterior where it’s is partially exposed. My basement walls a mostly subgrade with about 12 inches above grade. As I spray foam I orginally had intended to spray up the concrete directly over my sill plate right up to the subfloor.
I see elsewhere a theory that water pushes in traps itself behind the closed cell foam and through capillary action goes upward into my sill plate ( no damp proofing ) and accelerates the rot process dramatically. Around my sill plate is the draughtiest spot in my basement so I would really like to be able to spray foam all the way to the subfloor but am scared to accelerate rot in my very old sill plate.
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