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Attic insulation is the highest-impact, best-value energy upgrade in most homes — heat rises, and an under-insulated attic bleeds money year-round. It costs $1 to $4 per square foot installed in 2026, or roughly $1,700–$2,500 for a typical attic.
What you’re paying for
The bulk is the insulation material and labor, but two add-ons matter: air sealing (closing the gaps and penetrations that let conditioned air escape) and removing old insulation if it’s damaged, moldy, or pest-soiled. Skipping air sealing is the most common way attic insulation underperforms.
Cost by type
The material sets the price. The table below shows typical installed pricing per square foot.
How much R-value do you need?
Insulation is rated by R-value (resistance to heat flow), and attics need a lot — the Department of Energy recommends roughly R-49 to R-60 across most of the country. More R-value means more inches (and more cost), but attics are where it pays off fastest. If your existing insulation is below the joists, you’re under-insulated.
Air-seal first
The single best money you’ll spend is air sealing before insulating. Insulation slows heat flow but doesn’t stop air leakage; sealing the top plates, can-light penetrations, and the attic hatch first is what turns insulation into real savings. Many quotes bundle it — confirm it’s included.
How to save on attic insulation
- Choose blown-in for the best coverage-per-dollar on an attic floor.
- Air-seal first so the insulation actually performs.
- Check utility rebates — insulation is a commonly subsidized upgrade.
- DIY blown-in with a rental blower if you’re comfortable in the attic.
| Item | Typical range | Notes |
|---|---|---|
| Insulation material + install | $0.80 – $5 / sq ft | – |
| Air sealing | $250 – $750 | – |
| Old insulation removal | $1 – $1.50 / sq ft | – |
| Baffles / attic prep | $100 – $500 | – |
| Option | Typical range | Notes |
|---|---|---|
| Batt / rolled (fiberglass) | $0.80 – $2.60 / sq ft | – |
| Blown-in (cellulose / fiberglass) | $0.90 – $2.40 / sq ft | Best for attic floors |
| Spray foam (open / closed cell) | $1.50 – $5.00 / sq ft | Air-seals and insulates |
What affects the price
- Insulation type & R-value Higher R-value (more inches) costs more; your climate sets the target (often R-49–R-60 for attics).
- Attic size Priced per square foot, so larger attics cost more in total.
- Air sealing Sealing gaps and penetrations before insulating is what makes it actually perform — a worthwhile add-on.
- Old insulation removal Removing damaged, moldy, or pest-contaminated insulation adds $1–$1.50 per square foot.
Attic insulation cost by state
Where you live can change the price as much as the options you pick. Labor is a big part of the bill, and construction workers are paid more in some states than others. A typical attic insulation job costs about $1.15 to $4.70 per sq ft in Hawaii (17% above the U.S. average). In Arkansas, it costs about $0.85 to $3.40 per sq ft (15% below the U.S. average).
See the typical cost in all 50 states and D.C.
| State | Typical range |
|---|---|
| Alabama | $0.85 – $3.50/sq ft |
| Alaska | $1.15 – $4.60/sq ft |
| Arizona | $0.95 – $3.80/sq ft |
| Arkansas | $0.85 – $3.40/sq ft |
| California | $1.10 – $4.50/sq ft |
| Colorado | $1 – $4/sq ft |
| Connecticut | $1.05 – $4.30/sq ft |
| Delaware | $1 – $3.90/sq ft |
| District of Columbia | $1.10 – $4.30/sq ft |
| Florida | $0.90 – $3.65/sq ft |
| Georgia | $0.90 – $3.70/sq ft |
| Hawaii | $1.15 – $4.70/sq ft |
| Idaho | $0.95 – $3.75/sq ft |
| Illinois | $1.15 – $4.60/sq ft |
| Indiana | $1 – $4.05/sq ft |
| Iowa | $0.95 – $3.90/sq ft |
| Kansas | $0.95 – $3.80/sq ft |
| Kentucky | $0.95 – $3.70/sq ft |
| Louisiana | $0.90 – $3.60/sq ft |
| Maine | $1 – $3.90/sq ft |
| Maryland | $1 – $4/sq ft |
| Massachusetts | $1.15 – $4.60/sq ft |
| Michigan | $1 – $4/sq ft |
| Minnesota | $1.10 – $4.35/sq ft |
| Mississippi | $0.85 – $3.50/sq ft |
| Missouri | $1 – $4.10/sq ft |
| Montana | $1 – $3.90/sq ft |
| Nebraska | $0.95 – $3.75/sq ft |
| Nevada | $1.05 – $4.10/sq ft |
| New Hampshire | $1 – $3.95/sq ft |
| New Jersey | $1.15 – $4.55/sq ft |
| New Mexico | $0.90 – $3.70/sq ft |
| New York | $1.10 – $4.40/sq ft |
| North Carolina | $0.90 – $3.60/sq ft |
| North Dakota | $1 – $4.05/sq ft |
| Ohio | $1 – $4/sq ft |
| Oklahoma | $0.90 – $3.65/sq ft |
| Oregon | $1.10 – $4.40/sq ft |
| Pennsylvania | $1 – $4.05/sq ft |
| Rhode Island | $1.05 – $4.15/sq ft |
| South Carolina | $0.90 – $3.65/sq ft |
| South Dakota | $0.90 – $3.60/sq ft |
| Tennessee | $0.90 – $3.70/sq ft |
| Texas | $0.90 – $3.65/sq ft |
| Utah | $0.95 – $3.75/sq ft |
| Vermont | $0.95 – $3.90/sq ft |
| Virginia | $0.95 – $3.80/sq ft |
| Washington | $1.15 – $4.65/sq ft |
| West Virginia | $0.95 – $3.80/sq ft |
| Wisconsin | $1.05 – $4.15/sq ft |
| Wyoming | $1 – $3.95/sq ft |
These are numbers to plan with, not quotes. Each one is this guide's U.S. range, adjusted for what construction workers earn in that state. See every state cost guide or how we estimate.
Common questions
- How much does it cost to insulate an attic?
- Most attics run $1–$4 per square foot installed, or about $1,700–$2,500 total. Blown-in and batt are cheapest; spray foam costs the most.
- What R-value do I need for my attic?
- It depends on climate — the U.S. Department of Energy recommends roughly R-49 to R-60 for attics in most of the country. Your installer sizes the depth to hit the target.
- Batt vs. blown-in vs. spray foam — which is best?
- Blown-in is fast and great for covering attic floors evenly; batt is cheap for accessible joist bays; spray foam costs more but air-seals and insulates in one step, ideal for sealing a roofline.
- Does attic insulation pay for itself?
- Often yes — it's one of the highest-ROI energy upgrades, typically paying back in a few years through lower heating and cooling bills, and improving comfort immediately.
- Are there rebates for attic insulation?
- Many utilities offer insulation rebates, and some state programs help with weatherization. Federal energy-efficiency credits for insulation have tightened — check current local programs.
- Should I air-seal before insulating?
- Yes. Air sealing gaps, top plates, and fixture penetrations first prevents insulation from being undermined by air leakage — it's the step that makes the insulation work.
How we estimate: These are typical U.S. prices for materials and for hiring a pro to install them. We checked them against the 2026 sources listed below (see how we get our numbers). Your price depends on where you live, the size of the job and the materials you pick. Get two or three written bids before you choose a contractor.
Sources
We checked the prices on this page against 2026 numbers from these sources: