Insulation & energy estimator · Updated June 2026
Attic Insulation Cost Calculator
Attic insulation costs $1,500 to $4,000 for a typical home, or $1.50 to $4.00 per square foot installed. Use our free calculator to price your project by material and target R-value — and see your estimated energy savings and payback period.
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Enter your attic floor area to calculate your instant cost estimate and energy savings.
- Most attics cost $1,500–$4,000 to fully insulate
- The DOE recommends R-49 to R-60 for most of the US
- Attic insulation has the fastest energy payback of any home upgrade — often just 3–5 years
- A federal tax credit covers 30% of cost, up to $1,200/year
What affects attic insulation cost?
- Material — Blown-in fiberglass/cellulose is the affordable standard; spray foam costs 2–4x more but air-seals as it insulates.
- Target R-value — Higher R-values require more material, though savings show diminishing returns above R-60.
- Existing insulation — Topping up existing insulation costs far less than starting from bare joists.
- Removal — Damaged, moldy, or pest-contaminated insulation must be removed before new material goes in.
- Air sealing — Closing gaps around lights, plumbing and top plates before insulating often doubles your energy savings.
- State — Labor costs in California and the Northeast run 25–30% higher than Midwest and Southern states.
How much does attic insulation cost in 2026?
Attic insulation costs $1,500 to $4,000 for a typical home, or roughly $1.50 to $4.00 per square foot installed depending on material. Blown-in fiberglass and cellulose — the most popular attic options — run about $1.40 to $2.00 per square foot, while spray foam runs $1.50 to $4.50 or more per square foot depending on open-cell vs. closed-cell. Use our free calculator above for an instant estimate, plus your projected energy savings and payback period.
Attic insulation cost calculator — by material
| Material | Cost per sq ft installed | R-value per inch |
|---|---|---|
| Fiberglass batts | $0.90–$1.80 | R-2.9–3.8 |
| Blown-in fiberglass/cellulose | $1.40–$2.00 | R-3.2–3.8 |
| Open-cell spray foam | $1.50–$3.00 | R-3.7 |
| Closed-cell spray foam | $2.00–$4.50+ | R-6.5 |
What R-value do I need for my attic?
The US Department of Energy recommends different attic R-value targets depending on your climate zone. As a rule of thumb, most attics benefit from R-38 to R-49; colder regions should target R-60.
| Climate zone / region | Recommended R-value |
|---|---|
| Zone 1–2: Florida, Hawaii, deep South | R-30 minimum |
| Zone 3: Southeast, Texas, Arizona | R-38 |
| Zone 4: Mid-Atlantic, Appalachia | R-38–49 |
| Zone 5: Midwest, Northeast, Pacific NW | R-49 |
| Zone 6–7: Upper Midwest, Mountain West | R-49–60 |
| Zone 8: Alaska | R-60+ |
How much will attic insulation save me?
The EPA estimates that homeowners who air seal and add attic insulation save an average of 15% on heating and cooling costs — often more for homes that were severely under-insulated. For a typical 1,000–1,200 sq ft attic going from bare joists to R-49, that translates to roughly $300 to $500 per year in energy savings. Attic insulation delivers the fastest payback of any home energy upgrade — typically just 3 to 5 years — since uninsulated attics can account for 25–30% of a home's total heat loss. Our calculator above estimates your specific annual savings and payback period based on your inputs.
Is there a tax credit for attic insulation?
Yes. The federal Energy Efficient Home Improvement Credit (Section 25C) covers 30% of insulation costs — including installation — up to $1,200 per year through 2032. Unlike windows and doors, where only material costs qualify, insulation credits under 25C cover labor too. Air sealing work also qualifies. Claim it using IRS Form 5695. Many states and utility companies offer additional rebates on top of the federal credit — check energystar.gov/rebates for programs in your area.
Blown-in vs. batt insulation for attics
| Factor | Blown-in | Batts |
|---|---|---|
| Best for | Irregular joists, obstructions, most attics | Evenly-spaced, accessible joists |
| DIY-friendly | Moderate — rentable blower machines | Yes — easiest DIY option |
| Coverage of gaps | Excellent — conforms around everything | Fair — requires precise cutting |
| Best choice when | Attic isn't regularly accessed | Attic is used for storage/equipment access |
Frequently asked questions
How do I estimate attic insulation cost?
Measure your attic floor square footage, assess your current insulation level, choose a target R-value based on your climate zone, and select a material. Our calculator combines all of these automatically — as a rule of thumb, budget $1.50 to $4.00 per square foot depending on material.
How accurate is this attic insulation cost calculator?
Our estimates are typically within 15–25% of contractor quotes for standard attics. Actual pricing depends on attic complexity, obstructions, and whether existing insulation needs removal. Always get 3 quotes from certified insulation contractors.
What is the average cost to insulate an attic?
Most homeowners pay $1,500 to $4,000 to insulate a typical attic, or $1,800 to $3,500 for a standard 1,000–1,200 sq ft attic at R-38 to R-49 with blown-in insulation.
How much can I save on energy bills with attic insulation?
The EPA estimates a 15% average reduction in heating and cooling costs from air sealing and adding attic insulation, often translating to $300–$500 per year in savings for a typical home, with a payback period of 3 to 5 years.
Should I remove old insulation before adding new?
Only if it's damaged, water-stained, moldy, or pest-contaminated. If existing insulation is still in decent shape, you can typically add new material on top to reach your target R-value without removing anything.
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Disclaimer: All attic insulation cost and savings estimates are for informational purposes only based on average 2026 US contractor rates and published EPA/ENERGY STAR/DOE data. Actual costs and savings vary based on attic condition, climate, existing air sealing, energy usage and contractor availability. Tax credit eligibility depends on current IRS rules — consult a tax professional. Always obtain multiple quotes from certified insulation contractors before proceeding with any project.