Things You Will Need
The second option is to insulate the crawl space ceiling, which is the living space floor, protecting it from thermal loss. You can strap insulation, but it must be done to code.
-
Cut 2-to 4-inch strips of 4-mil poly vapor barrier with your utility knife. You will need several of these to properly support the crawl space insulation.
-
Crawl into the crawl space with the plastic strapping, a hammer tacker, and your measuring tape. Set the strapping and hammer taker to the side for the time being and go to one end of the crawl space. Measure off the crawlspace wall 24 inches and mark on the floor joist. Perform this on every few floor joists all the way across the crawl space. Perform this in the entire crawl space, marking every 24 inches.
-
Staple the plastic strapping strips onto the bottom of the floor joists with the hammer tacker. This will keep the insulation from falling out of the cavities. Use your marks to keep the pieces straight. Make sure that the strapping is tight to keep the insulation up against the bottom of the floor sheathing.