Little or no insulation in the basement rim joist could be the problem, allowing . Because sealing up this one little area is a no brainer for the added comfort and . What About Insulating the Rim Joist? After air sealing the rim joist area it is relatively easy to insulate each cavity with rigid foam insulation or fiberglass batts. If using batts, just cut the insulation to fit and place against the rim joist without compression, gaps, or voids. If using rigid, foam into place. Comfort & energy efficiency starts with a properly-insulated basement . Seal & insulate the rim joist: The edge of the house where the floor framing rests on the . Three ways to make your basement better with insulation. Seal & insulate the rim joist: The edge of the house where the floor framing rests on the foundation is a major source of air leakage and energy loss. Insulate foundation walls: Rigid foam insulation is best for your basement's concrete walls. Dec 1, 2014 - . for insulating my basement rim joists? very small basement, very old . lower your energy bills and increase the comfort of your basement. 4. Did you know that you can save money on energy just by sealing rim joists and sill plates? Find out how to do it with Great Stuff Insulating Foam Sealants. . quickly and easily, helping to make the home more comfortable and less drafty for . cracks around plumbing lines and rim joists, in attics and basements, and more. Adding spray foam to your basement or crawl space's rim joists can help seal air from entering and exiting your home, making it more comfortable for you and . May 10, 2018 - . LLC installs Wall, Attic, Crawl Space, Basement/Rim Joist insulation in . but also controls acoustics, moisture and improves your comfort of .