Attic Insulation Cost: $1,700 to $2,500 + R-Values (2026)

How much does attic insulation cost

Installed prices for adding or replacing attic insulation. Removal of old insulation, air sealing and contamination cleanup are extra.

HomeAdvisor puts the 2026 national average at $2,100, with most homeowners paying $1,700 to $2,500. HomeGuide's January 2026 guide says $1,000 to $2,700, with a national average of $1,800, and notes that some companies set a $1,500 to $2,000 minimum project. Material, depth and whether old insulation has to come out first all change the price. Labor alone runs $0.50 to $1.30 per square foot in HomeGuide's figures and $1.50 to $3 in HomeAdvisor's.

Attic insulation cost per square foot by type

Installed price per square foot. The guides price the same materials differently; ask each company to quote per square foot at a stated R-value.

Blown in insulation cost

Blown-in is a common way to top up an attic floor. HomeGuide's blown-in guide puts the average job at $800 to $3,000, a national average of $1,900, and $900 to $3,600 for an attic floor. By attic size: $900 to $2,400 for 1,000 square feet and $1,350 to $3,600 for 1,500 square feet. Fiberglass and cellulose cost about the same installed.

Spray foam insulation cost

Spray foam sits at the top of the price range. HomeGuide puts it at $1.50 to $5.00 per square foot and $3,000 to $8,000 for an attic, with minimum job fees of $1,000 to $2,000 or more. Open-cell foam runs R-3.5 to 3.7 per inch; closed-cell runs R-5 to 7 per inch at a higher price. If foam goes on the underside of the roof deck, ask the installer how attic ventilation and any equipment up there will be handled.

Spray foam is a professional job. CPSC staff guidance says residents should leave during installation and stay out for at least 24 hours afterward, that the foam's A side contains isocyanates, and that people with asthma or respiratory allergies may want a different insulation. HomeGuide adds that codes generally require a fire barrier such as drywall over spray foam in living spaces.

Recommended R-value for an attic by climate zone

The R-value measures how well insulation resists heat flow. The Department of Energy and ENERGY STAR both publish attic targets by climate zone, and they differ slightly in the warmest zones:

Attic floor targets for existing homes. Your installer can tell you your climate zone.

How deep that is depends on the material. For blown-in insulation, HomeGuide prices each target per 1,000 square feet of attic:

HomeGuide blown-in insulation guide, Nov 2025.

Attic insulation removal cost

Fixr says removal is usually unnecessary when existing insulation is in good condition and you are only adding more. HomeGuide lists the reasons it has to come out: water damage, mold, fire or smoke damage, rodent nests and droppings, and vermiculite that may contain asbestos. HomeGuide puts removal at $1 to $2 per square foot, or $1,600 to $3,600 for a typical 1,600 to 1,800 square foot attic, and blown-in costs more to remove than batts.

Contaminated attics cost more.

Attic cleaning after rodents, water or mold

If the insulation is wet, find the leak before anything new goes in; roof leak repair covers tracing it, and leak detection covers hidden plumbing leaks. Mold on the roof deck or rafters is a separate job: mold remediation lists attic mold removal prices. If you check rodent droppings yourself, the CDC says to air the space out for 30 minutes first, wear rubber or plastic gloves, never sweep or vacuum droppings or nests, and soak them with disinfectant or 1 part bleach to 9 parts water for 5 minutes before wiping up. The CDC says heavy infestations call for respirators and coveralls.

Air sealing: do it before you insulate

Insulation slows heat moving through the ceiling; it does not stop air leaking through gaps around lights, pipes, wires and the attic hatch. The DOE calls air sealing and moisture control important to energy efficiency, health and comfort. Air sealing costs $350 to $3,000 in HomeGuide's figures and $250 to $750 in HomeAdvisor's. Once new insulation is down, the gaps are buried, so ask whether sealing is in the quote.

DIY vs pro attic insulation

HomeGuide says batts, blown-in and loose-fill suit DIY, and spray foam does not. It puts DIY blown-in at $0.35 to $1.50 per square foot, or $500 to $1,200, with machine rental at $100 to $200 a day; some stores lend the blower free when you buy 10 to 20 or more bags. Its attic guide prices 5 inches of DIY loose-fill over 1,000 square feet at $200 to $650. Hire a pro for spray foam, for anything contaminated, for vermiculite, and if the attic is tight or hot. Once up there, step only on the joists or on boards laid across them.

Is there a tax credit for attic insulation in 2026

No federal tax credit. The 25C Energy Efficient Home Improvement Credit covered insulation and air sealing materials (not labor) within a $1,200 annual cap, but the IRS says it applied only to property placed in service from January 1, 2023 through December 31, 2025. Insulation installed in 2026 is priced without it.

Two places to look instead. The DOE's Home Energy Rebates are "available in select states": the HEEHR program (up to $14,000) covers insulation, air sealing and ventilation, and HOMES (up to $8,000) covers insulation and air sealing for projects modeled to save at least 20%. Contact your state energy office. Also ask your electric or gas utility whether it runs an insulation program, and whether it requires a participating contractor before work starts.

How long does attic insulation last

HomeGuide's lifespans: fiberglass 80 to 100 years in ideal conditions, though it suggests checking it after 15 to 20 years; cellulose 20 to 30 years, starting to degrade around year 15; spray foam 80 years or more on an attic floor if undisturbed, and up to 30 years on the roof deck. The spray foam figure assumes it is left undisturbed, and water, mold or pests are reasons to replace any type early.

Attic insulation near me: what to ask before you book

• What R-value and depth? The quote should name the target R-value, the material, and the installed depth, so you can check it with a ruler afterward.
• Is air sealing included? Ask which gaps they seal (light fixtures, top plates, plumbing and wiring holes, the hatch) and what that line costs.
• What about the soffit vents? Ask how they keep new insulation from blocking the eave vents, usually with baffles. Attic ventilation explains why it matters.
• Does the old insulation stay or go? Get removal, disposal and any sanitation fee as separate lines.
• For spray foam: how long you must stay out, how they ventilate the work area, and who covers it with a fire barrier where required.
• License and insurance: CPSC staff suggest verifying a foam contractor's training, insurance and licenses. Rules vary by state; ask which license applies where you live.

If someone pitches a powered attic fan as the fix for a hot upstairs, read attic fan installation first. Federal building research recommends passive ventilation over attic fans and lists more insulation and air sealing as fixes for a hot attic. For ice dams, see ice dam removal. Insulation is one line on the home repair costs list; if you are buying, see home inspection cost.

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