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Price by square feet, material and R-value target — before the energy audit becomes an upsell. No signup. ·
Blown-in cellulose runs $1.20–3.20 per sq ft installed and blown fiberglass $1.00–2.50 (Bob Vila; TLS Energy Savers bands overlapped), with batts in the same $1.00–2.50 range, closed-cell spray foam at $1.50–4.00, and open-cell at $1.50–2.55 (about $0.50–0.85 per board foot at a ~3 in roofline). A typical 1,000 sq ft attic lands at $1,000–3,500 all-in — the band Angi ($987–2,335), Thumbtack ($1,193–3,077) and TLS ($1,500–3,500) all agree on.
Roughly 1.7× the standard price: cellulose reaches $2.00–3.50 per sq ft at R-60 depth and batts $2.50–4.00 (R-60 project data). The number that justifies it is not the sq ft price — it is the energy audit's before/after load calculation. Sell the audit first; the insulation sells itself off the auditor's numbers.
Only when it is wet, moldy, pest-soiled or vermiculite-suspect — removal is a separate hazardous disposal job with its own day count, and blowing new loft over clean, dry existing insulation is standard practice. Quote removal as its own line so the insulation price stays honest.
For open attics, blown-in wins on cost and coverage: it fills joist gaps batts bridge, and the machine pays for itself across a crew-day. Batts suit accessible, standard-spaced joists and DIY. Spray foam is for converting the attic to conditioned space (roofline insulation), not for the floor: open-cell runs $0.50–0.85 per board foot and buys air sealing and sound dampening at the lower price; closed-cell runs roughly double per board foot and adds rigidity plus a moisture barrier. Different job from the floor — different quote.
| Material / depth | Installed per sq ft (2026) |
|---|---|
| Blown-in cellulose, standard | $1.20 – $3.20 |
| Blown-in fiberglass, standard | $1.00 – $2.50 |
| Fiberglass batts, standard | $1.00 – $2.50 |
| Spray foam (closed cell) | $1.50 – $4.00 |
| Open-cell spray foam, ~3 in | $1.50 – $2.55 ($0.50–0.85 / board ft) |
| R-60 depth multiplier | ≈ ×1.7 on band |
| Typical whole attic (1,000 sq ft) | $1,000 – $3,500 |
Keep going with these tools — they build on this calculation: Material Cost Estimator, Contractor Hourly Rate Calculator and Drywall Repair Cost Calculator.
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In 2026 US data: blown-in cellulose $1.20–3.20 per sq ft installed, blown fiberglass and batts $1.00–2.50, closed-cell spray foam $1.50–4.00, open-cell $1.50–2.55 per sq ft installed ($0.50–0.85 per board foot at ~3 in). A typical 1,000 sq ft attic project lands at $1,000–3,500 (Angi; Thumbtack; TLS).
Most US climate zones target R-49–60 for attics — roughly 16–20 inches of loose-fill cellulose. Topping an under-insulated attic up to R-38 costs meaningfully less than the full R-60 upgrade, which prices at about 1.7× the standard band.
Installed, they overlap: blown cellulose $1.20–3.20 vs batts $1.00–2.50 per sq ft. Blown-in usually wins on real attics because it fills irregular joist bays and wire clutter batts bridge — the air gaps are where R-value dies.
Only if it is wet, mold-contaminated, pest-soiled or possibly asbestos-containing vermiculite. Clean, dry insulation accepts new blow-over directly; removal is a separate disposal line item — keep it out of the insulation quote.