Need advice on surface temperature and spraying to 2-part foam
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I got the 2-part foam kit to deal with the leaky band joist in the crawl space (it is attached to the full basement). This whole week I kept the tanks by the heat vent, so they are nice and toasty at 70 degrees.
I also diverted one of the vents into crawl space and got steady air temperature at 62 there in preparation to spraying. I thought several days would get the band joist to about same temperature, but Boston weather is not helping me, so I have about 54 degree surface temps.
Question: kits says I need 60-degree surface and air temperature. Should I scrap the project and wait until May? Or 6 degree surface temperature difference is just splitting hairs?
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Replies
Be conservative here. The risk/reward of gambling with temperature on 2-part foam is definitely not in your interest. You would live with the consequences of a poor choice for years or perhaps decades afterward.
I ended up making sure both chemicals were at 80 degrees, crawlspace air was at 67, though surface ended up being about 55, I used a trick I found through research - make 1st layer less than half an inch, which warms up the surface.
Came out just fine, but I am not going to do that again. Too nerve-wracking.