How to Install Basement Insulation

Insulating your basement is something that can save you money in times of higher energy costs by keeping your house cooler in the heat and warmer in the cold months. Installing basement insulation is not difficult if you use the proper tools and take the right approach.

Things You'll Need

• Expanding foam
• Plastic sheets
• Asphalt sealant
• Caulk gun
• Safety glasses
• Dust mask
• Tape measure
• Blanket insulation
• Insulation knife
• Insulation hangers
• Extruded polystyrene foam
• Caulk
• Drywall
• Rigid insulation
• Nail
• Utility knife and blades
• 1-inch by 3-inch wood strapping
• Level
• Stepladder

Instructions

Prepare to Install Insulation

1. Seal the joints between the mud sill, or the framing member that rests on top of the foundation. Expanding foam works well in this application.

2. Use plastic sheeting to cover the outside of the wall, Cover the wall only from the point where it touches the ground and downward.

3. Adhere the sheeting to the wall with asphalt sealant. Apply the asphalt sealant with a caulking gun.

Install Blanket Insulation

1. Check the top of the walls of the basement to see if there are exposed perpendicular joists on top of the foundation.

2. Use an insulation knife to cut the blanket insulation into pieces small enough to go between the joists. Make sure you press the paper backing of the insulation back against the joist band.

3. Insert wire insulation hangers to secure the insulation in place.

4. Measure and cut squares of extruded polystyrene foam to fit between against the joist band. Use caulk to seal all the way around the extruded polystyrene foam.

5. Insert the blanket insulation against the extruded polystyrene foam, then install drywall to fireproof the insulation.

Install Rigid Insulation

1. Measure the rigid insulation and cut it as needed. Cut the rigid insulation by scoring the backing with a nail then cutting it with a utility knife.

2. Measure and cut 1-inch by 3-inch strapping so it's the same length as the rigid insulation.

3. Fit the rigid insulation to the wall, the backing side out. If necessary, trim the insulation to fit with the utility knife. Use a level to make sure the rigid insulation is plumb.

4. Fit a second sheet next to the first, and slip a piece of strapping along the seam to hold both in place.

5. Drill pilot holes in the middle of the strapping. Clean any debris and secure the strapping to the wall with masonry screws. Continue the process all the way around the basement.

6. Install rigid insulation around pipes and electrical panels by putting a piece of strapping on either side. Use expandable foam to fill in the space in between.

7. Extend the jambs around the windows by nailing a board that's wide enough to extend beyond the rigid insulation.

References

• Cepco Tool - Insul-Knife Insulation Knife
• Insulate The Basement Walls
• Installing Rigid Insulation