spray foam insulation not drying

Old 11-04-19, 04:03 AM
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spray foam insulation not drying

I had my crawl space ceiling sprayed with closed cell spray foam insulation. It went well, but I noticed today about a square foot where the spray foam did not adhere to the basefloor and did not dry. it's kind of just droops down and is all gooey. The space doesn't smell or anything like that. Should I just ignore it and hope it dries over time or is this a sign that something went horribly wrong?
Old 11-04-19, 04:33 AM
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It depends on the type of spray foam used. Some single part foams cure in the presence of water vapor. If it's that type it should eventually cure if the foam is still good. You can also speed the process by spritzing it lightly with water. Two part foams cure with a chemical reaction. If it's still soft and uncured then I would guess the foam is bad or it was not properly mixed.
Old 11-04-19, 04:56 AM
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If you had it done then it's 2 part and that means the area won't cure, something was wrong with the installation.

I'd be calling the company back to tear it out and re apply!
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Old 11-05-19, 09:20 AM
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This is one of my misgivings about the consumer versions of two part spray foam. If even professional spray foam crews with commercial level equipment can screw up, seems odds of DIY screwups using consumer equipment, which, as far as I know, has no regulators on the two feed lines, are high. If that mix isn't right, the foam doesn't cure correctly.

OP, just because you don't smell anything doesn't mean the uncured foam isn't off-gassing. I'd call the company right away.
Old 11-06-19, 12:35 AM
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I had my crawl space ceiling sprayed with closed cell spray foam insulation
I read that as you having hired out the job which means it's time to call them back to finish it.

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