Spray Foam Insulating Crawl Space With Dirt Floor

Some people say we can get foam insulation sprayed in which will harden on the dirt floor.

Spray foam insulating crawl space with dirt floor.

However the insulation needs to be treated with a fire retardant. Or you can insulate the entire perimeter with spray foam for 1700. We are currently power venting the crawl space to protect against radon gas. This type of crawl space also allows insulation with an r value of 19 installed in the floor joist if the crawl space and has a permanently installed dehumidifier.

Insulating a vented crawl space if you would like to keep your crawl space vented because you live in a low humidity environment we recommend insulating the crawl space floor with fiberglass or rock wool mixed with spray foam for air sealing. We are not sure if i should insulate the ceiling of the crawl space or to simply try to get a floor. When we insulate the walls of the crawl space we lay down plastic over the dirt floor that is a vapor barrier. You could also use batt insulation but don t.

The standard 6 mil poly vapour barrier will work fine as a diy solution. For those with nothing but a dirt floor the single most important thing to do will not cost much cut off the moisture supply to the air by laying down polyethylene directly on the ground. To insulate the crawl space i would use a closed cell two pound 907 gram spray foam because it will act as both your vapour barrier and insulation. This is the technique we use when insulating a crawl space with a dirt floor.

This type of insulation allows for conditioned air to be introduced into the crawl space. Cover the walls with insulation from the sill plate to the plastic covered dirt floor. Retrofoam of michigan has been insulating crawl spaces with foam insulation for more than 15 years. This means you can insulate the entire crawl space with fiberglass insulation for 1500.