How Much Does It Cost to Insulate a House?
Updated
Insulating a house costs about $1–$2.40 per square foot for fiberglass batts, $1–$2.50 for blown-in, and $3–$7 for spray foam, installed. A typical attic runs $1,500–$3,500. The attic gives the fastest energy payback, so start there.
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Cost by insulation type
- Fiberglass batts: $1.00–$2.40/ft²
- Blown-in cellulose: $1.00–$2.50/ft²
- Spray foam: $3.00–$7.00/ft²
Where to spend first
The attic loses the most heat, so bringing it to R-38–R-60 delivers the biggest savings per dollar. Air-seal gaps before adding insulation for full performance.