# Attic Insulation Cost Calculator

This is the text version of https://www.hiresupertrades.com/calculators/attic-insulation-cost-calculator.

Attic insulation installation for a typical attic averages about $2,100, and most homeowners pay $1,500 to $3,500. This calculator prices attic insulation cost from $1.50 to $4 per sq ft. A 1,000 sq ft attic with blown cellulose, the usual blow in insulation, is about $2,000.

## Attic Insulation price breakdown

Typical job based on 1000 sq ft. Prices are supply-and-install midpoints. Actual quotes vary.

| Type | Cost per sq ft | Typical 1000 sq ft job |
| --- | --- | --- |
| Blown fiberglass | $2 | $1,500 |
| Blown cellulose | $2 | $2,000 |
| Open-cell spray foam | $3 | $2,500 |
| Closed-cell spray foam | $4 | $4,000 |

## What affects Attic Insulation cost

- **Insulation material:** Blown fiberglass is $1.50 per sq ft. Blown cellulose is $2 per sq ft and is the usual blown-in attic. Open-cell spray foam is $2.50 per sq ft. Closed-cell spray foam is $4 per sq ft. Fiberglass batts in an open attic usually cost about the same as blown fiberglass and are not a separate choice here.
- **Attic size:** Enter the attic floor area. A typical attic is about 1,000 sq ft, close to the home's footprint. At the cellulose rate that is about $2,000. An 800 sq ft attic is about $1,600, and a 1,500 sq ft attic is about $3,000.
- **Old insulation:** Adding over dry insulation is included in the base rate. Removing wet, moldy, or pest-damaged fill adds $1.50 per sq ft. On a 1,000 sq ft attic that is an extra $1,500. Air sealing around pipes, lights, and wiring is often $250 to $1,500 and is not included.
- **Minimum job pricing:** Very small attics use an $800 minimum. If the square-foot math comes in lower, the estimate starts at $800. Displayed estimates are plus or minus 20 percent around the midpoint.

## Frequently asked questions

### How much does attic insulation cost for a 1,000 sq ft attic?

For 1,000 sq ft, blown fiberglass is about $1,500, blown cellulose is about $2,000, open-cell spray foam is about $2,500, and closed-cell spray foam is about $4,000. The national average project is about $2,100, so the cellulose price is the closest match. The displayed range is plus or minus 20 percent. Removing old fill adds $1,500 on this size attic.

### What is the average blown in attic insulation cost?

Blown in attic insulation is $1.50 per sq ft for fiberglass and $2 per sq ft for cellulose. On 1,000 sq ft that is about $1,500 or $2,000. The displayed ranges are about $1,200 to $1,800 for fiberglass and about $1,600 to $2,400 for cellulose. Most homeowners pay $1,500 to $3,500 for the whole project.

### How much does spray foam insulation cost in an attic?

Spray foam insulation cost is $2.50 per sq ft for open-cell foam and $4 per sq ft for closed-cell foam. On 1,000 sq ft that is about $2,500 or $4,000. Closed-cell is the premium attic and sits above what most homeowners spend. Those prices do not include removal of the old fill.

### Does attic insulation installation cost more if the old insulation has to come out?

Yes. Attic insulation installation over dry fill uses the base rate. Removing wet, moldy, or pest-damaged insulation adds $1.50 per sq ft. On 1,000 sq ft of cellulose, the job moves from about $2,000 to about $3,500. Air sealing is separate and is often $250 to $1,500.

### Is cellulose insulation more expensive than blow in insulation with fiberglass?

Yes. Cellulose insulation is $2 per sq ft, and blow in insulation with fiberglass is $1.50 per sq ft. On a 1,000 sq ft attic that is about $2,000 for cellulose and about $1,500 for fiberglass. Both sit in the usual blown-in range.

### Is there a minimum charge for attic insulation installation?

Yes. If the square-foot price is under $800, the estimate starts at the $800 minimum. A typical 1,000 sq ft attic is above that. A radiant barrier, sometimes added in a hot climate, is often $0.10 to $2 per sq ft and is not included.