Uninsulated rim joists are huge energy losers. Now's the time to insulate and seal your rim joists. One option is to seal the rim joists with rigid insulation cut to fit. We recommend a minimum of 2-in.-thick extruded polystyrene, but check your local codes to see what's required. If you have a table saw, use it to cut strips equal to the depth of your joists. Then use a fine-tooth handsaw, utility knife or miter saw to cut the strips to length. Fill small gaps with caulk, and larger ones wit...
