Blown-in insulation bags per 1,000 ft² by target R

Typical published planning values — NOT a certified design. Real performance depends on installation quality, framing / thermal bridging, moisture and settling; follow the product data sheet and your local energy code. Foam ignition/thermal-barrier, vapor/moisture control and combustion-air safety are set by the manufacturer and code — check with a professional.

Loose-fill blown insulation is sold by the bag, and each bag covers less area as you fill deeper for a higher R. The table below shows bags per 1,000 ft² at each target R from the labeled coverage-per-bag-at-R chartread the chart printed on YOUR bag. Use it with the blown-in bag calculator and the attic bag calculator.

Target RCoverage per bag (ft²)Bags per 1,000 ft²
R-13108 ft²/bag10 bags
R-1974 ft²/bag14 bags
R-3047 ft²/bag22 bags
R-3837 ft²/bag28 bags
R-4928 ft²/bag36 bags
R-6023 ft²/bag44 bags

Labeled coverage-per-bag-at-R chart (blown fiberglass) — a higher R means a deeper fill and fewer ft² per bag. Read the chart on YOUR bag and blow a little deep to allow for settling.