Insulation Cost Guide 2026: Attic, Wall, and Crawlspace Insulation Pricing
How much insulation installation costs in 2026 by type and location — attic, wall, and crawlspace — with R-value requirements and payback period estimates.
Insulation Costs by Type (2026)
- Blown-in fiberglass/cellulose (attic): $1.00–$2.50/sq ft installed. Most common attic upgrade. $800–$2,000 for typical 1,200 sq ft attic.
- Fiberglass batts (walls/floors): $0.40–$1.50/sq ft installed. Standard for new construction wall cavities.
- Spray foam (closed-cell): $1.50–$4.50/sq ft installed. Best thermal and air-sealing performance. 2-inch application = R-13 closed-cell. Typical crawlspace: $2,000–$6,000.
- Spray foam (open-cell): $0.80–$2.00/sq ft. Better sound dampening, lower R-value than closed-cell.
- Rigid foam board: $0.25–$0.90/sq ft materials only; add labor for installation.
Where to Insulate for Best ROI
Attic is the highest-priority location — heat rises, so inadequate attic insulation is the biggest thermal loss in most homes. Recommended R-value varies by climate zone: R-38 (hot climates, zone 1–2) to R-60 (cold climates, zone 6–8) for attics. Crawlspaces and rim joists are second priority; walls of existing homes are expensive to insulate and often not cost-effective unless already open during renovation.
Insulation Payback Period
Adding attic insulation from R-11 to R-38 in a typical home: $600–$1,500 cost. Typical annual savings: $200–$500. Payback period: 2–5 years. Insulation is one of the highest-ROI home improvements available for existing homes — far better energy payback than window replacement.