How To Insulate Basement Floor Joists

Two story homes usually have another ring of rim joists above the first floor ceiling.

How to insulate basement floor joists.

Cut the insulation to length using a square and sharp utility knife. Also insulate 4a any portion of the floor in a room that is cantilevered beyond the exterior wall below. Once the ceiling is buttoned up insulate the rim joist the floor framing around the perimeter of the house directly above the foundation wall. Rigid foam is affordable.

It s the simplest and least expensive basement area to insulate and will bring the highest return on your investment. Spiders bugs and even mice find the rim joist an attractive place to enter the home. If you have an unfinished basement you can properly insulate the rim joists in two or three hours. Use a box cutter to cut the insulation to length.

Insulating the space between the joists in a basement or crawlspace can help reduce your energy bills. 4d extend insulation into joist space to reduce air flows. Fiberglass insulation batts or rolls are the most economical and easiest diy choice for insulating between the floor joist in a crawl space. If you re ready to insulate the rim joists in your basement or crawlspace you have to decide between rigid foam and spray foam.

Rim joists let in more than air. When the basement or crawl space has vents installed insulating joist bays. It is important to also seal and insulate the top of the concrete wall where the sill plate sits. Department of energy recommends r 11 3 insulation under floors in warm climates and an r 25 6 to 8 in cold climates.

Hold the batts in place by stapling their paper faced vapor retarders to the lower edges of the joists. 4b slab floors built directly on the ground. Properly insulating and air sealing rim joists band joists takes patience so most builders simply stuff in some fiberglass and walk away. If you need to insulate these rim joists it s best to hire a cellulose insulation contractor.