Insulating A Crawlspace

A crawlspace is an unfinished, accessible area below the first floor of a building. Proper insulation can help protect your living space from outside temperature changes.

There are two types of crawlspaces: vented and unvented. Vented crawl spaces open to the outside, while an unvented crawl spaces is part of the basement.

In a vented crawlspace, the underfloor should be insulated — much aslike it is in ceilings. This may be done before or after the subfloor has been installed. JM ComfortTherm®, Kraft-faced and unfaced insulation are all possible products to use for this application. With Kraft-faced insulation, the facing is generally against the subfloor.

In an unvented crawlspace, you should insulate the perimeter walls.

Filter Products By
  • Project Type
  • Install Type
Recommended Products
AP™ Foil
AP™ Foil-Faced Polyiso Foam Sheathing provides continuous insulation for maximum... more
Kraft-Faced Batts & Rolls
JM Kraft-faced Formaldehyde-free™ fiberglass insulation offers R-values ranging... more
Unfaced Batts & Rolls
JM Unfaced Formaldehyde-free™ fiberglass insulation offers R-values ranging from... more
TempControl® Mineral Wool
JM TempControl® Mineral Wool insulation is made from high-density... more
Related How-To Guides
Install in a Crawlspace
This video will take you through the steps you’ll need to insulate a crawlspace.
Install Around Objects
This video will guide you through the process of placing insulation around... more