How Much Insulation to Use

In most homes, but especially in older homes, adding insulation in the attic will cut heat loss. At a minimum, homes should have attic insulation between R-22 and R-49 (6 to 13 in. of loose fill or 7 to 19 in. of fiberglass batts). Check with the local building department to find the recommended level for your area. Stick your head through the attic access door and measure how much insulation you have. If your insulation is at or below the minimum, adding some will lower your heating bills. If you need to add more, go with loose-fill insulation rather than fiberglass batts even if you already have fiberglass. Loose fill is usually composed of cellulose or fiberglass and lets you cover joists and get into crevices.