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Seal cove joint and other basement slab cracks prior to insulating?

MSlagel | Posted in General Questions on

I’m getting ready to insulate and finish the basement in our 3-year old house.  Their are a few cracks in the slab and walls –only one of them is significant (4-5 mm width)– but no signs of heaving or water infiltration anywhere.  
Instinctively, I want to fill this crack and also the cove joint (gap between walls and floor) with a concrete caulk/sealant BEFORE I apply EPS insulation to walls and slab.  Is there any good reason to actually do that?  If so, is there a recommended product type (e.g. epoxy vs polyurethane) for doing so?

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  1. charlie_sullivan | | #1

    I think it's smart to seal them and reduce risk of future water ingress and reduce air coming in, carrying radon and moisture.

    Polyurethane or butyl rubber sealant are both good on concrete. Both also have nasty fumes, so I would work with good ventilation and a respirator rated for VOCs. Or use an alternative like Contega HF which is lower toxicity though not as robust.

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