Best Insulation For Floor Joists In Crawl Space

Lay an insulating mat over the crawl space floor.

Best insulation for floor joists in crawl space.

Where winter temperatures are extreme opt for insulating the walls and sealing off the crawl space entirely. Floor insulation for moderate climes popular reads. Department of energy recommends r 11 3 insulation under floors in warm climates and an r 25 6 to 8 in cold climates. Fiberglass insulation is usually the best option though handling fiberglass can be dangerous and it is not the most eco friendly option in some cases.

Dim light filtered in from vents in the walls. Don t compress the insulation as it requires its loft in order to maintain its rated r value. In moderate or dry climates without the threat of sustained subfreezing temperatures insulation between floor joists makes sense. Stapling fiberglass batts between joists to the underside of your home s floor presents a number of problems.

Crawl space insulation basics. While this method does work in the very short term moisture eventually builds in the crawl space and grows on this highly porous surface. If your space has them avoid adding insulation to the crawl space walls. 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.

Instead of installing the foam insulation between floor joists in the crawl space the foam board is installed against the crawl space foundation walls. The insulation should press right up against the floor between joists. Batts of soggy fiberglass insulation hung haphazardly from the joists. Unlike fiberglass rigid foam insulation does not absorb water support mold or allow air to pass through.

Fiberglass insulation batts or rolls are the most economical and easiest diy choice for insulating between the floor joist in a crawl space. This type of insulation allows for conditioned air to be introduced into the crawl space. Use an insulation that. It is important to secure insulation and cover it with a vapor barrier in order to prevent moisture and the mold that often follows close behind.

The best insulation material for crawl spaces is rigid foam insulation board. Instead install fiberglass batting between the joist bays which are the spaces between each set of floor joists. However the insulation needs to be treated with a fire retardant.