Attic Insulation Cost Calculator
Estimate attic insulation cost for blown-in, batt or spray foam. Enter attic square footage to get a low, typical and high price, labor vs. materials and cost per sq ft.
Estimated total
- Low
- $1,300
- Typical
- $2,350
- High
- $3,750
$2.35 per sq ft all-in (range $1.30–$3.75)
Where the money goes (typical)
- Materials
- $968 (41%)
- Labor
- $1,383 (59%)
Line items (typical)
| Blown-in fiberglass or cellulose (to about R-38) | $1,750 |
| Air sealing (top plates, wiring holes, attic hatch) | $600 |
Fastest and usually cheapest. Fills around joists, wiring and odd shapes.
General U.S. estimates for installed cost, not quotes. We compared them with national per-square-foot ranges from HomeGuide, Angi and HomeAdvisor for blown-in, batt and spray foam attic insulation. Prices reviewed November 2026. Get at least three local quotes before you commit.
Attic insulation is priced per square foot of attic floor for blown-in and batt insulation, and per square foot of roof deck (or per board foot) for spray foam. The price depends mostly on the type of insulation, how deep it goes and whether old insulation has to come out first.
Enter your attic area, choose a type and add removal or air sealing if you need them. The result shows a realistic range, how much of it is labor, and the cost per square foot.
How the attic insulation cost estimate works
- Enter the attic floor area in square feet.
- Multiply it by the installed price per sq ft for the material you chose.
- Adjust for attic access and your local cost level.
- Add the extras you ticked, such as removal, and any permit fee.
- Show the result as a low, typical and high total, split into materials, labor and fees.
For blown-in or batts, the attic floor area is about the same as the ceiling area of the rooms below. Spray foam goes on the underside of the roof, which is roughly 10% to 30% larger, so add that for foam quotes.
Attic Insulation Cost by material
| Material | Installed per sq ft | Labor share | Notes |
|---|---|---|---|
| Blown-in fiberglass or cellulose (to about R-38) | $1.00–$2.75 | 55% | Fastest and usually cheapest. Fills around joists, wiring and odd shapes. |
| Fiberglass batts (to about R-38) | $1.00–$3.00 | 50% | Rolls or pre-cut pieces laid between joists. Popular for DIY in open attics. |
| Open-cell spray foam (roof deck) | $2.00–$4.50 | 50% | Seals air leaks as well as insulating. Usually sprayed under the roof deck. |
| Closed-cell spray foam (roof deck) | $3.00–$6.00 | 50% | Highest R-value per inch and a vapor barrier. Most expensive option. |
Attic Insulation Cost by size
Typical total with the low–high range below it. Assumes easy: walk-up or roomy attic; average u.s.; air sealing (top plates, wiring holes, attic hatch).
| Attic floor area | Blown-in fiberglass or cellulose (to about R-38) | Fiberglass batts (to about R-38) | Open-cell spray foam (roof deck) | Closed-cell spray foam (roof deck) |
|---|---|---|---|---|
| 500 sq ft | $1,500$800–$2,400 | $1,500$800–$2,500 | $2,100$1,300–$3,250 | $2,750$1,800–$4,000 |
| 1,000 sq ft | $2,350$1,300–$3,750 | $2,400$1,300–$4,000 | $3,600$2,300–$5,500 | $4,850$3,300–$7,000 |
| 1,500 sq ft | $3,250$1,800–$5,150 | $3,300$1,800–$5,500 | $5,100$3,300–$7,750 | $7,000$4,800–$10,000 |
| 2,000 sq ft | $4,100$2,300–$6,500 | $4,200$2,300–$7,000 | $6,600$4,300–$10,000 | $9,100$6,300–$13,000 |
| 2,500 sq ft | $5,000$2,800–$7,900 | $5,100$2,800–$8,500 | $8,100$5,300–$12,250 | $11,250$7,800–$16,000 |
What affects attic insulation cost
- Insulation type. Blown-in and batts cost about the same per square foot. Spray foam costs two to three times more but also seals air leaks.
- Target R-value. Most U.S. climates call for R-38 to R-60 in the attic. Going from R-38 to R-60 adds roughly half again as much material.
- Old insulation removal. Wet, moldy or rodent-damaged insulation must come out first, typically $1 to $2.25 per square foot with vacuum equipment.
- Air sealing and prep. Sealing gaps around wiring, plumbing and top plates before insulating adds a few hundred dollars but makes the insulation work much better.
- Rebates. Utility rebates and federal or state energy programs often cover part of the cost. Check what is available before you sign.
Frequently asked questions
How much does attic insulation cost?
For a 1,000 square foot attic, blown-in or batt insulation typically costs $1,300 to $4,000 including basic air sealing. Spray foam on the roof deck usually costs $2,300 to $7,000 or more.
How much does blown-in attic insulation cost per square foot?
Installed blown-in insulation generally costs $1 to $2.75 per square foot for about R-38, depending on depth and local labor rates.
Is spray foam insulation worth it in an attic?
Spray foam makes sense when you want a sealed, conditioned attic, such as when HVAC ducts run through it. For a simple vented attic, blown-in insulation gives most of the energy savings for much less money.
How much insulation do I need in my attic?
The U.S. Department of Energy recommends R-30 to R-60 depending on climate zone. In most of the country that means about 10 to 20 inches of blown-in insulation.
Should old attic insulation be removed before adding new?
Not if it is dry and clean; new insulation can go right on top. Remove it if it is wet, moldy, contaminated by pests, or if you need to air seal the attic floor first.
About these figures
General U.S. estimates for installed cost, not quotes. We compared them with national per-square-foot ranges from HomeGuide, Angi and HomeAdvisor for blown-in, batt and spray foam attic insulation. Last reviewed November 2026. Your price depends on your home, your region and the contractor, so treat this as a budget range and compare it with written quotes.