Insulating Basement Adjacent to Crawlspace
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Hello, I would like to insulate and finish my basement according to the great info on this site. Climate zone 6a.
It seems straight forward, except there is an insulated crawl space next to one full side (36ft) of the basement (from an addition). I don’t know the details exactly (I can get in there and investigate if relevant) but within the crawl space, the foundation walls are covered in thermax sheathing and the dirt floor is covered in poly. Seems to be sealed up well. There is no insulation on the floor above, and the area above the crawl space does have colder floors in the winter.
Right now, with exterior temps at 50* (nights have been below freezing for the last few weeks), when I temp the interior basement CMU walls with an IR thermometer, the crawl space side near the top is 69 to 70*, and near the basement floor its 64-69*, depending how close to the center/side I measure. On the opposite side of the basement, the interior CMU temps at 59-60* near the top and 62* near the floor.
So my question is what to I do with the crawl space side. I’m thinking I should be able use less insulation and maybe even only insulate ground level and below, or only insulate the wall near the edges of the crawl space and not the middle section. I’m also unsure if I should further address the crawlspace itself, perhaps with additional insulation?
Thank You!
Tyler
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Replies
Decided to leave the crawlspace alone and insulate the shared wall with 1.5" polyiso.