Reverse swimming pool crawlspace?
I have a 1960’s ranch with a full basement under 80% of the house. The other 20% is over a crawlspace that’s connected to the full basement. The crawlspace is known to take on 4″-6″ of water in heavy rain, and being coastal Rhode Island this isn’t uncommon (zone 5). There’s no sump, but the water always disappears anyway and appears to be dry until the next storm. The floor of the crawlspace is a rat slab right on top of dirt, so it seems that what doesn’t become vapor just gets absorbed back into the ground
I need to encapsulate the crawlspace and know that part of the water problem is most likely drainage from outside due to the slope of the yard. Excavation and drainage from the outside is out of budget for now.
Does it make sense to air seal the rim joist with rigid foam, then lay poly on the floor/walls and tape the seams like crazy to keep the water under the poly, like a pool cover, until the exterior drainage can be taken care of? Or will this cause other problems?
Thank you for any help – hope I got all the details in there.
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