Best Insulation For Floor Joists In Crawl Space

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.

Best insulation for floor joists in crawl space.

Stapling fiberglass batts between joists to the underside of your home s floor presents a number of problems. Fiberglass insulation batts or rolls are the most economical and easiest diy choice for insulating between the floor joist in a crawl space. Don t compress the insulation as it requires its loft in order to maintain its rated r value. Department of energy recommends r 11 3 insulation under floors in warm climates and an r 25 6 to 8 in cold climates.

If the crawl space is ventilated which is ideal because it aids in the elimination of moisture then fiberglass insulation can be easily installed under the subfloor between the floor joists. If your space has them avoid adding insulation to the crawl space walls. Where winter temperatures are extreme opt for insulating the walls and sealing off the crawl space entirely. Lay an insulating mat over the crawl space floor.

The insulation should press right up against the floor between joists. 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. Fiberglass rolls can be placed between joists but the fiberglass itself will need to be cut to fit properly between joists. While this method does work in the very short term moisture eventually builds in the crawl space and grows on this highly porous surface.

However the insulation needs to be treated with a fire retardant. This type of insulation allows for conditioned air to be introduced into the crawl space. In moderate or dry climates without the threat of sustained subfreezing temperatures insulation between floor joists makes sense. Use an insulation that.

Crawl space insulation basics. Floor insulation for moderate climes popular reads. 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.

Gaps between the insulation and the floor can. Unlike fiberglass rigid foam insulation does not absorb water support mold or allow air to pass through. Dim light filtered in from vents in the walls.