Not damp/waterproofing a foundation?
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Would it be foolhardy to not damp/waterproof our foundation? We have a very sandy site and low water table. We will be putting 6 inches of foam on the foundation (the foam is ship lapped).
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Is any concrete touching soil anywhere? If so, what are you saving vs what are you risking? Isn't it a pennies and minutes vs dollars and days deal? It seems like cheap insurance to me.
Jessie,
Q. "Would it be foolhardy to not damp/waterproof our foundation?"
A. Yes. In addition to being foolhardy, it would be a code violation. Foundation dampproofing requirements can be found in Section R406.1 of the 2006 IRC.
It is sort of pennies and minutes vs dollars and days thing. It is getting chilly here so we will have to use dimple mat to waterproof instead of a tar coating of some kind, due to the weather conditions (on and off damp - wet foundation wall - and now quite cold, -10 degrees celcius). We are reluctant to spend the money on the dimple mat given that the sight is so sandy and well drained. I have not found a paint-on damp proofing that can be applied at such low temperatures. Any suggestions?