The original post: /r/diy by /u/EvanLeeWest on 2024-11-13 20:05:39.

Good afternoon all.

I am working on a back to the studs reno on the portion of my home that was build in 1935 located in south east Michigan. This reno will include the crawlspace. The crawl in this area of the home is dirt 12" from the bottom of the floor joists and totally un-encapsulated, this joins into the portion of the home that was built in the 90s and that is 24" deep under the floor joists and also unencapsulated dirt. I plan to dig out the 1935 portion along the center to be 24" deep sloping up to the foundation walls at a 1:1 slope ending about a foot from the walls. after that is complete the current plan is to encapsulate the crawl in the entire house with 20mil plastic extending up and attached to the foundation walls. Then I plan to use Fomular XPS to insulate the joist bays and foundation walls over top of the encapsulation plastic (leaving a termite inspection gap), seal off all vents, and install a permanent dehumidifier. Should I Do anything for floor insulation under the encapsulation plastic or will the plastic and wall insulation be enough to help with cold floors? Looking for general advice and thoughts on this plan.