How to Put Insulation in Basement Eaves
- 1). Cut the end of a tube of caulk on an angle with a utility knife. Pierce the inner seal with the piecing tool attached to the caulk gun. Place the caulk into a caulk gun. Start in one corner and inspect each section of the band joist between and along the floor joists for areas where plumbing lines, electrical lines, cable wires go through the band joist. Squeeze a bead of caulk around each pipe, line or wire to air seal the space. In addition, squeeze a bead of caulk along each band joist where the ends of two band joists intersect. The goal is to prevent all air movement between the basement and the outside of the home.
- 2). Start from one corner of the basement. Use either rigid foam or blanket insulation to fill the space between the top of the basement wall and the floor boards. Measure the height of the space with a tape measure.
- 3). Cut pieces of foam board or blanket insulation to the height of the space between the top of the basement wall and the floor boards. Measure from the end of the insulation and draw a straight line across the coated side of the insulation. Cut foam insulation with a hand saw with a fine-tooth blade. Cut blanket insulation by placing the cut line over a section of ¼-inch plywood. Lay another piece of plywood on top and, while pressing down on the top piece of plywood, cut the insulation with a sharp utility knife.
- 4). Install foam board insulation by adding glue to the back of the insulation and pressing in place against the band joist. Use a utility knife to cut the pieces to fit around pipes or wires. Unfold the side edges of blanket insulation and use a staple gun to staple the sides of the insulation in place. Do not press blanket insulation into the space; compressing blanket insulation reduces the R-value of the insulation.