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 Much Does Attic Insulation Cost in 2026?

How Much Does Attic Insulation Cost?

Typical cost (per sq ft, installed)

$1 – $4 / sq ft

National average: $1,700–$2,500 per attic

Range gauge · per sq ft, installed

Avg $2

Low $1 $4 High

Estimate your cost

Adjust the options for a tailored ballpark — figures and the regional adjustment are approximate estimates. Always confirm with local quotes before you budget.

Quality / scope

Square feet

Your state

Estimated cost $2 $2 – $2

Typical mid-point for your selections

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.

Cost breakdown
Component	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	—

Cost breakdown

Component

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

—

Cost by insulation type (installed, per sq ft)
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

Cost by insulation type (installed, per sq ft)

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.

Frequently asked 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: ranges reflect typical U.S. pricing for materials and professional installation, compiled and cross-checked against the current (2026) industry sources listed below (see our data & methodology). Your actual cost depends on your location, project size, material grade, and local labor rates — always get multiple written quotes before you commit.