- 1). Check the wall you are insulating for leaks or other problems before insulating. Address these issues, if present, before proceeding.
- 2). Measure the distance from the floor to the ceiling joists and cut a length of rigid foam insulation at that measurement with your utility knife.
- 3). Stand the insulation up against the wall and ensure it is plumb with a level.
- 4). Cut another piece of insulation at the correct length and stand it up next to the first piece.
- 5). Cut a furring strip at the same length as the insulation with your saw and place it up to the beveled indentation that is created where the two pieces of insulation meet.
- 6). Drill through the furring strip with a masonry bit into the concrete wall behind. Fasten with a concrete screw. Fasten the strip approximately every 16 inches along its entire length.
- 7). Install each successive piece of insulation in the same manner until your entire wall is insulated.
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