How Much Does Insulation Cost in 2026?
National ranges, materials + labor, professionally installed · Pricing data updated · Reviewed annually
Insulating an average ~1000 sq ft attic, installed with air sealing, costs $900 to $3,000 in blown-in cellulose, $1,000 to $3,000 in blown-in fiberglass, $2,200 to $4,100 in open-cell spray foam, and $3,000 to $6,000 in closed-cell foam. Material is the biggest lever — a roughly 6× spread. The full spectrum is wide: a small batt job in a low-cost region can start near $300, while a whole-attic closed-cell foam job in a high-cost metro can exceed $16,200.
Two things move an insulation budget more than the sticker price of the material: the R-value your climate zone requires, and whether you air-seal first. Both come first below, then the per-square-foot and whole-attic ranges, an interactive estimator, the board-foot math for spray foam, and a hand-off to the free insulation calculator for a materials takeoff.
How much R-value your attic needs (2021 IECC)
Before pricing anything, fix the target. The 2021 IECC sets these attic/ceiling minimums by climate zone — higher than the older R-38/R-49 numbers still circulating from the 2015 and 2018 editions. Find your zone with the free climate zone calculator.
| Climate zone | Attic / ceiling target | Notes |
|---|---|---|
| CZ 0–1 | R-30 | Hot / hot-humid (S. FL, HI, Gulf). Zone 0 is new to 2021 and shares Zone 1. |
| CZ 2–3 | R-49 | Warm South & Southwest. Up from R-38 in the 2015/2018 IECC. |
| CZ 4–8 | R-60 | Mixed to subarctic. The 2021 IECC raised CZ4 from R-49 to R-60. |
Raised-heel-truss exception (2021 IECC R402.2.1): installing R-49 over 100% of the ceiling satisfies an R-60 requirement wherever the full height of uncompressed R-49 extends over the wall top plate at the eaves — a common way to hit code without over-filling.
Insulation cost by material (installed, per sq ft)
The starting point for any insulation budget is the material. These are installed rates — materials plus labor — before air sealing, removal, or a code-plus R-60 target. Attic loose-fill and batt rates cover topping an accessible attic floor; spray-foam rates are for a roofline application at a realistic thickness (foam is priced per board-foot in the trade — the section below shows the conversion).
| Material | Installed / sq ft | Application & R basis |
|---|---|---|
| Blown-in cellulose~3.2–3.8 / inch (settled) | $0.90 – $3.00 | Attic floor, topping existing R-19 up to R-49 (~10–13" settled). Highest recycled content; settles ~15–20%, so blown depth must exceed the settled target. |
| Blown-in fiberglass~2.5 / inch | $1.00 – $3.00 | Attic floor, same R-19→R-49 delta (~13–16" loose fill). Lighter than cellulose, will not settle or wick moisture. |
| Fiberglass batts~3.1–3.4 / inch | $0.75 – $2.60 | R-13/R-15 in a 2×4 wall cavity or R-30/R-38 rolled over an accessible attic floor. Cheapest DIY material but gaps/compression cut real R. |
| Open-cell spray foam~3.6 / inch | $2.20 – $4.10 | Roofline / underside of deck at ~5.5" (≈R-20). Air-seals in one step; vapor-open, so pairs with a smart retarder in cold climates. Priced per board-foot in the trade. |
| Closed-cell spray foam~6.5 / inch | $3.00 – $6.00 | Roofline or rim joist at ~3" (≈R-19.5). Highest R per inch, adds structural rigidity and a vapor barrier. Priced per board-foot; pro-only. |
| Rigid foam board (XPS/polyiso)for comparison | $1.00 – $2.50 | Continuous exterior/basement-wall board at ~1". Polyiso R-value drops in cold; EPS/XPS hold steady. |
| Radiant barrier (reflective)for comparison | $0.50 – $2.20 | Cuts COOLING ~5–10% in hot, sunny attics with HVAC/ducts up there; little winter benefit. Not a substitute for insulation. |
Whole-attic cost by material and size
Installed, national averages, before air sealing or removal of old insulation. Each cell is a low-to-high range; real projects cluster toward the middle. Knee walls and low-clearance attics add roughly 15–25% for the awkward access.
| Attic size | Blown-in cellulose | Blown-in fiberglass | Fiberglass batts | Open-cell spray foam | Closed-cell spray foam |
|---|---|---|---|---|---|
| Small attic500 sq ft | $450 – $1,500 | $500 – $1,500 | $400 – $1,300 | $1,100 – $2,050 | $1,500 – $3,000 |
| Average attic1000 sq ft | $900 – $3,000 | $1,000 – $3,000 | $750 – $2,600 | $2,200 – $4,100 | $3,000 – $6,000 |
| Large attic1500 sq ft | $1,350 – $4,500 | $1,500 – $4,500 | $1,150 – $3,900 | $3,300 – $6,150 | $4,500 – $9,000 |
| Whole-attic2000 sq ft | $1,800 – $6,000 | $2,000 – $6,000 | $1,500 – $5,200 | $4,400 – $8,200 | $6,000 – $12,000 |
Estimate your insulation project
Combine material, attic size, region, and the real-world site conditions to see your range update live. Air sealing is on by default — it's the highest-return companion line. Each add-on shows what it adds before you commit.
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What the site conditions add
Priced against a typical project — an average 1000 sq ft cellulose attic at the national rate. These conditions ride on top of the material cost. On a bigger attic or a pricier material the per-sq-ft ones scale up proportionally.
| Factor | What's involved | Adds |
|---|---|---|
| Air-seal the attic (recommended) | Seal top-plates, penetrations, and the attic hatch before insulating. Per ENERGY STAR, air sealing + insulation saves ~15% on heating & cooling; skipping it wastes part of the insulation spend. On by default. | +$300 – $600 |
| Remove old / contaminated insulation | Vacuum out and bag old, wet, or rodent-fouled insulation before the new goes in. Homes pre-~1990: TEST for vermiculite/asbestos first — abatement is a separate hazmat job. | +$1,000 – $2,000 |
| Code-plus R-60 target (CZ 4–8) | Step the attic from an R-49 to an R-60 target — roughly 8 more bags of blown material per 1,000 sq ft. The 2021 IECC minimum for climate zones 4–8. | +$200 – $450 |
| Knee walls / low-clearance attic | Complex, low-headroom, or knee-walled attics add ~15–25% for the extra time and awkward access. | +$150 – $750 |
| Baffles + bath-fan / vent corrections | Install soffit baffles to keep the airflow path clear, add a roof vent, and re-route any bath fan exhausting into the attic before insulating. | +$150 – $700 |
| Cathedral / vaulted ceiling | Insulating a vaulted or cathedral ceiling adds ~10–30% for access and the tighter rafter-bay detailing. | +$100 – $900 |
Spray foam: price it by the board-foot
A spray-foam quote in "$/sq ft" is meaningless without a thickness — the trade prices foam by the board-foot (a 1 ft × 1 ft area sprayed 1 inch deep). Fix the inches and the target R-value, then convert. Closed-cell delivers far more R per inch but costs 2–3× the board-foot rate.
| Foam type | Per board-foot | Thickness → R | Resulting / sq ft |
|---|---|---|---|
| Open-cell~R-3.6/inch | $0.40 – $0.75 | 3.5" → R-12.6 (Wall cavity) | $1.40 – $2.60 |
| 5.5" → R-20 (Roofline / cathedral) | $2.20 – $4.10 | ||
| Closed-cell~R-6.5/inch | $1.00 – $2.00 | 2" → R-13 (Rim joist / wall) | $2.00 – $4.00 |
| 3" → R-19.5 (Roofline (unvented)) | $3.00 – $6.00 |
A foam quote in "$/sq ft" is meaningless without a thickness — always confirm the inches and the R-value the sprayer will hit, not just the dollars.
Cost by region
Labor is a meaningful share of any insulation job, so local rates move the whole number. The same average 1,000 sq ft blown-in cellulose attic across regions:
| Region | Typical areas | Cellulose attic | Closed-cell foam |
|---|---|---|---|
| Lower-cost region | Rural South, Midwest, Mountain West | $750 – $2,550 | $2,550 – $5,100 |
| National average | Most metros | $900 – $3,000 | $3,000 – $6,000 |
| High-cost metro | NYC, SF, Boston, Seattle, HI, AK | $1,200 – $4,050 | $4,050 – $8,100 |
Air sealing: the highest-ROI companion
Air sealing is the one line you should never skip. Per ENERGY STAR: homeowners save an average of 15% on heating & cooling (about 11% on total energy) by air sealing and adding insulation in attics, floors over crawl spaces, and basements. DOE puts air-sealing-first savings at 15–30%. As a companion to a blown-in job it typically adds $300–$600; as its own standalone visit it runs $350–$2,500. Adding R-value over a leaky attic floor lets convective air loss overwhelm the conductive gain — you pay for insulation the leaks then defeat.
Beyond a simple attic top-up
Some insulation jobs are their own scope, not a straightforward attic top-up. Typical all-in ranges:
| Job | Typical total | What it covers |
|---|---|---|
| Deep attic retrofit (~2,000 sq ft) | $3,500 – $6,750 | Air-seal + baffles + blow to R-49 or higher — the full "do it once" attic package. |
| Rim-joist + basement/crawl foam | $2,750 – $9,250 | Closed-cell on rim joists and crawl/basement walls. Rim-joist-only runs ~$2,000–$2,300; full basement walls + rim runs $4,500–$9,200. |
| Dense-pack existing walls (per 1,000 sq ft) | $1,500 – $4,200 | Drill-and-fill "net-and-blow" of closed wall cavities — its own high-pressure rig, not the consumer rental blower. |
DIY vs. hiring a pro
Blown-in is the only genuinely DIY-friendly attic job — Home Depot and Lowe's rent the blower free with a minimum bag purchase, and the machine does the hard work. Spray foam (chemistry, PPE, cure/ventilation) and dense-pack walls (a high-pressure rig, not the consumer blower) are pro-only. Materials-only cellulose budgets to hit R-49:
| Attic size | Cellulose materials only |
|---|---|
| Small attic500 sq ft | $150 – $400 |
| Average attic1000 sq ft | $300 – $500 |
| Large attic1500 sq ft | $450 – $750 |
| Whole-attic2000 sq ft | $600 – $1,050 |
Materials only. Big-box stores rent the blower free with ~10–20 bags; third-party rental runs $100–$200/day. Blown-in coverage is bag-count-per-1,000-sq-ft on a SETTLED-depth basis — do not reuse a batt bundle figure for loose fill. Spray foam and dense-pack are NOT DIY (chemistry, PPE, cure/ventilation, and a high-pressure rig).
Federal tax credit: gone for 2026
The federal 25C Energy Efficient Home Improvement Credit (historically 30% of qualifying material cost, capped at $1,200/yr for insulation + air sealing) was TERMINATED December 31, 2025 by the One Big Beautiful Bill Act (OBBBA, PL 119-21). The controlling event is "placed in service" — insulation placed in service in 2026 gets NO federal 25C credit (confirmed by IRS FS-2025-05 / IR-2025-86). Only projects completed on or before 12/31/2025 can be claimed on the 2025 return. Ignore any page still claiming "30% through 2032."
Utility rebates are highly variable — some utilities (e.g. Mass Save, Oncor) offer per-sq-ft insulation/air-sealing incentives or no-cost weatherization. Check the ENERGY STAR Rebate Finder and the DSIRE database before relying on one.
How to choose — and keep the cost down
Air-seal before you add R-value. It's the cheapest, highest-return step, and it makes every dollar of insulation actually perform. Doing it in the same visit as a blown-in job is far cheaper than a separate trip.
Match the material to the assembly. An open, accessible attic floor → blown-in, the best R-per-dollar. A vaulted ceiling, rim joist, or unvented roofline where you need air sealing and R in one step → spray foam. Don't pay foam prices for a job blown-in does better.
Hit your zone's target, not more. Going past code-required R buys diminishing returns. Stepping R-49 to R-60 in a cold zone is cheap; over-filling past R-60 rarely pays back.
Test before you touch old insulation. In a pre-1990 home, vermiculite or asbestos turns a simple removal into a licensed hazmat job. A ~$250–$850 test up front is far cheaper than an accidental disturbance.
Nail the square footage before you call for bids. The insulation calculator gives you a defensible area and bag count to check bids against.
What these ranges don't include
National ranges, materials + labor combined, for insulation professionally installed to a modern R-target. Attic loose-fill and batt rates cover topping an accessible attic floor; spray-foam rates cover a roofline application at a realistic thickness. Removing old insulation, a code-plus R-60 target, hard-access or knee-wall attics, ventilation-baffle corrections, and cathedral complexity are priced as separate adjusters. Asbestos/vermiculite abatement, mold remediation, roof repairs, structural work, and whole-house energy audits are excluded — see the exclusions below. These are planning ranges, never a quote; get at least three written, itemized bids from licensed local contractors.
- Asbestos / vermiculite abatement (add $10–$25/sq ft) — Test first (~$250–$850). Vermiculite removal commonly runs $7,000–$12,000 — a licensed hazmat job, never DIY.
- Mold remediation (roughly $1,500–$6,000) — Attic mold from prior moisture problems must be remediated before insulating.
- Roof repairs — Active leaks or failing decking are a separate roofing scope — insulate a dry attic only.
- Structural work — Reframing, decking, or rafter repair to carry a new load is priced on its own.
- Whole-house energy audit (roughly $200–$700) — A blower-door + infrared audit averages ~$437 nationally; the 25C audit credit also expired after 12/31/2025.
- HVAC / duct work — Sealing or relocating attic ductwork is a separate mechanical scope.
Where these numbers come from
Ranges reconcile the code and coverage standards that set the spec — the 2021 IECC (Table R402.1.3), the FTC R-value rule (16 CFR 460), and manufacturer coverage charts — with the aggregators that set installed pricing (Angi, HomeGuide, Fixr, Forbes, HomeAdvisor), corroborated for foam by SCS Foam, sprayfoamcalc, and Thumbtack. Where sources diverged by more than 40% — attic blown-in most of all, where one aggregator tops out near $7.50/sq ft against a $1–$3 cluster from four others — we trusted the tighter cluster for a straightforward top-up and reserved the high end for hard-access, deep-fill, and removal scenarios. Every figure is rounded to the nearest $50 on purpose: a national estimate quoted to the dollar is false precision. The model is reviewed annually; this page was last computed from data updated . For your own project, the only numbers that beat these are the ones in a written bid from a licensed local contractor — get at least three.
Ready to price the actual job?
The free insulation calculator goes past ranges: enter your area and target R-value and it returns the material quantity — bags, batts, or board-feet — and a takeoff you can save, share, or hand to a contractor. No signup.
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Don't forget disposal in the budget
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Frequently Asked Questions
How much does insulation cost in 2026?
For an average ~1000 sq ft attic, professionally installed insulation runs $900 to $3,000 in blown-in cellulose, $1,000 to $3,000 in blown-in fiberglass, $2,200 to $4,100 in open-cell spray foam, and $3,000 to $6,000 in closed-cell foam — materials and labor included, air sealing added. Material is the biggest lever, spanning a roughly 6× range from blown-in to closed-cell foam. Size your exact job with the free insulation calculator.
How much does attic insulation cost per square foot?
Blown-in attic insulation clusters at about $0.90–$3.00/sq ft installed for cellulose and $1.00–$3.00 for fiberglass, both topping an existing attic floor up to R-49. Fiberglass batts rolled over an accessible attic run $0.75–$2.60/sq ft. Some listings quote attic blown-in as high as $7.50/sq ft — that reflects hard-access, deep-fill, or removal jobs, not a straightforward top-up.
How much does spray foam insulation cost?
Spray foam is priced by the board-foot, not the square foot — this is the trade's biggest source of quote confusion. Open-cell runs about $0.40–$0.75 per board-foot installed and closed-cell $1.00–$2.00. Converted to area at a realistic thickness, open-cell roofline (~5.5") lands around $2.20–$4.10/sq ft and closed-cell (~3") around $3.00–$6.00/sq ft. Always confirm the inches and target R-value, not just the dollars.
Is the federal insulation tax credit still available in 2026?
No. The federal 25C Energy Efficient Home Improvement Credit — historically 30% of qualifying material cost, capped at $1,200/year for insulation and air sealing — was terminated December 31, 2025 by the One Big Beautiful Bill Act (OBBBA, Public Law 119-21) and confirmed by IRS Fact Sheet FS-2025-05. The controlling event is "placed in service," so insulation installed in 2026 gets no federal 25C credit; only projects completed on or before December 31, 2025 can be claimed on the 2025 return. Ignore any page still claiming "30% through 2032." Utility rebates may still apply — check the ENERGY STAR Rebate Finder and DSIRE database.
Should I add air sealing when I insulate?
Almost always yes — it's the highest-ROI companion line and it's on by default in the estimator above. Per ENERGY STAR: homeowners save an average of 15% on heating & cooling (about 11% on total energy) by air sealing and adding insulation in attics, floors over crawl spaces, and basements. DOE puts air-sealing-first savings at 15–30%. Bundled with a blown-in job, air sealing typically adds $300–$600. Adding R-value over a leaky attic floor lets convective air loss overwhelm the conductive gain, so skipping it wastes part of the insulation spend.
What R-value do I need in my attic?
Under the 2021 IECC (Table R402.1.3), attic targets are R-30 in climate zones 0–1, R-49 in zones 2–3, and R-60 in zones 4–8 — higher than the older R-38/R-49 figures still circulating from the 2015/2018 editions. Stepping a 1500 sq ft attic from an R-49 to an R-60 target adds only about $300–$700 in material. Many jurisdictions still enforce the 2015 or 2018 code, so verify the locally required minimum with your building department. Find your zone with the free climate zone calculator.
Does removing old insulation add much to the cost?
Removal runs about $1.00–$2.00/sq ft to vacuum out and bag old, wet, or rodent-fouled material — on a typical ~1000 sq ft attic that's roughly $1,000–$2,000. One critical caveat: if the home predates about 1990 or vermiculite is present, test for asbestos first (~$250–$850). Abatement is a licensed hazmat job that is excluded from these ranges — never disturb suspect insulation yourself.
Can I install insulation myself?
Blown-in is the only genuinely DIY-friendly attic job — Home Depot and Lowe's rent the blower free with a minimum bag purchase, and cellulose materials for an average attic run about $300–$500. Buy by settled coverage per 1,000 sq ft (roughly 35–39 bags of cellulose at R-49), not by a batt figure. Spray foam and dense-pack walls are pro-only — foam involves chemistry, PPE, and cure/ventilation, and dense-pack needs a high-pressure rig, not the consumer rental blower.
Do these ranges include labor?
Yes — every installed range on this page combines materials and labor, reconciled from national industry sources. National ranges, materials + labor combined, for insulation professionally installed to a modern R-target. Attic loose-fill and batt rates cover topping an accessible attic floor; spray-foam rates cover a roofline application at a realistic thickness. Removing old insulation, a code-plus R-60 target, hard-access or knee-wall attics, ventilation-baffle corrections, and cathedral complexity are priced as separate adjusters. For a materials takeoff you can price yourself or hand to a contractor, run the free insulation calculator.