Insulation Tips for Homes

Insulate Outside

• With a house under construction, coat the exterior walls with rigid foamboard insulation, typically 1 inch thick and nailed to studs; seal seams at panel joints and around windows and doors with tape from the foamboard manufacturer. This is not an option with an existing house unless the old siding is removed.

Move Inside

• Staple fiberglass insulation batts between wall studs inside a house under construction. Batts have stapling flaps on each side and typically are 8 feet long and 16 inches wide to fit between studs. Cut batts with a utility knife to fit narrow stud spaces and around all utility outlets or other openings in walls. Seal joints between batts and around openings with plastic tape from the manufacturer. In an existing house, either remove drywall or cut openings in it to allow loose cellulose insulation to be blown into the wall cavity.

Use Attic Insulation

• Put blown-in insulation, typically cellulose, in the attic. Spray it between joists and the tops of wall cavities, but don't block necessary vents around soffits. Buy special plastic panels to allow for insulation without covering soffit vents. As an alternative, lay fiberglass batts between ceiling joists.

Use Decking with a Barrier

• Deck the roof with oriented strand board (OSB) that has a metallic moisture and air barrier on one side. Put that barrier down to block airflow up through the OSB panels.

Add Extra Insulation

• Add extra insulation inside by stapling fiberglass batts between ceiling joists. This will put a double layer of insulation at the tops of rooms, where heat is most likely to escape. Put similar insulation between ceiling joists in a basement, if there is one, and insulate basement walls with foamboard after thoroughly sealing with waterproofing paint.

Use Recommended Insulation

• Always use the recommended R value of insulation; R value is the resistance to heat, a measurement of effectiveness in blocking air transfer. Check manufacturer's recommendations for R value, which can vary widely depending on local climate.