Insulation For Floor Joists In Crawl Space

The best choice when it comes to installing insulation between the floor joists in a crawl space is fiberglass batts or rolls.

Insulation for floor joists in crawl space. This type of insulation may be faced with silver foil with the foil facing inward toward the crawl space. 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. Use caulk or foam sealant to seal the joint between the top. Install the insulation with the vapor barrier facing up toward the heated living area of the house.

If a crawl space is ventilated then insulation can be easily installed under the subfloor between the floor joists. View of second story floor joists from below. Blown in insulation is also an option though this can be messy and somewhat inefficient. In moderate or dry climates without the threat of sustained subfreezing temperatures insulation between floor joists makes sense.

Part of the problem with adding insulation for floor joists is securing such insulation between joists underneath the floor. Aluminum sheeting can also be used to insulate between joists but this may not be the most efficient method for floors. Fill the ends of joist bays with rectangles cut from rigid board insulation. Where winter temperatures are extreme opt for insulating the walls and sealing off the crawl space entirely.

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. This insulation material is economical and the easiest for do it yourself diy installation. In older homes where the spacing of the floor joists varies you may need to cut the insulation to width as well. Fiberglass insulation batts or rolls are the most economical and easiest diy choice for insulating between the floor joist in a crawl space.

Department of energy recommends r 11 3 insulation under floors in warm climates and an r 25 6 to 8 in cold climates. The sill plate is the first piece of framing lumber and it runs on top of the crawl space wall. Use foam sealant such as great stuff to seal the joints. Rigid foam insulation works for any type of masonry wall.

Cut pieces of insulation just large enough to fit along the rim joist the framing material into which all the floor joists are nailed. Concrete block brick and even stone. Floor insulation for moderate climes if your winter temps seldom linger below freezing you re in luck. Two inch expanded polystyrene foam board is the favored insulation for crawl space inside walls.