Attic Insulation Cost Calculator
Enter your attic size and climate zone to compare blown-in fiberglass, blown-in cellulose, fiberglass batts, and closed-cell spray foam - with material quantities, total cost, and energy payback. Covers both "attic insulation" and "blown-in insulation" searches in one tool.
Last updated: July 2026
DOE recommendation: R-49 for attic floors in Zone 5.
Irregular attic spaces, retrofit over existing insulation
Used to estimate energy savings and payback. US average is about $2,000/year.
Attic Insulation Estimate
Energy savings & payback
Price data sources: Angi 2026 Attic Insulation Cost · Angi 2026 Blown-In Insulation Cost · DOE Insulation Fact Sheet 2024 · IECC 2024 Climate Zone Map · ENERGY STAR insulation savings estimates
Last verified: July 2026
Material prices are US national averages from Angi 2026. Your local market may vary by ±30%. R-values from DOE/IECC.
For broader industry benchmarks, see our 2026 construction cost statistics.
How to Use This Attic Insulation Calculator
Step 1: Pick your climate zone. The Department of Energy splits the US into 7 zones. Zone 1 is Florida and Hawaii; Zone 7 is Alaska. The calculator auto-fills the DOE recommended attic R-value for your zone - R-30 in warm climates up to R-60 in the coldest.
Step 2: Choose a material. Blown-in fiberglass and cellulose are the value picks for most attics. Fiberglass batts are the cheapest and easiest DIY. Closed-cell spray foam gives the highest R per inch but costs 3 to 5 times more.
Step 3: Enter attic area and add-ons.Put in your attic floor square footage. Tick "remove old insulation" if the existing material is damaged, and "air sealing" if a pro will caulk and foam gaps first (recommended - it can add 10% more savings).
Step 4: Review costs and payback. The tool shows material quantity (bags, batts, or board feet), a line-item cost breakdown, total installed cost, and the energy payback period based on your annual heating and cooling bill.
Attic Insulation Materials Compared
| Material | R/inch | Material $/sq ft | Sold as |
|---|---|---|---|
| Blown-In Fiberglass | R-2.5 | $0.4-0.85/sq ft | bags |
| Blown-In Cellulose | R-3.5 | $0.5-1.3/sq ft | bags |
| Fiberglass Batts | R-3.2 | $0.4-1/sq ft | batts |
| Closed-Cell Spray Foam | R-6.5 | $1-1.5/board ft | board ft |
Material prices from Angi 2026 (blown-in at R-38 reference; scaled by target R-value). Spray foam priced per board foot (1 sq ft × 1 inch thick).
Attic Insulation Cost Breakdown
| Component | % of Total | What it covers |
|---|---|---|
| Insulation Material | 30-50% | Bags, batts, or spray foam - varies by material type and target R-value |
| Labor | 35-50% | Installation, prep, equipment (blower rental or spray rig) - $0.80-$3.00/sq ft |
| Old Insulation Removal | 10-15% | Optional - $1.00-$1.50/sq ft when existing insulation is damaged or contaminated |
| Air Sealing | 5-10% | Caulking and foaming gaps before insulating - $250-$750, critical for performance |
DOE Climate Zone R-Value Recommendations for Attics
Your climate zone sets the target R-value, which drives how much material you need. The map below is the Department of Energy reference. Colder zones need thicker insulation - R-60 in Zone 7 needs roughly twice the material of R-30 in Zone 1.
| Zone | Representative States | Attic R-Value | Thickness (cellulose) |
|---|---|---|---|
| Zone 1 | FL, HI, southern TX | R-30 | 10-12 in |
| Zone 2 | Gulf Coast, southern CA, AZ | R-38 | 13-15 in |
| Zone 3 | Southern US: Atlanta, LA, Dallas | R-38 | 13-15 in |
| Zone 4 | Mid-Atlantic, Pacific NW | R-49 | 16-19 in |
| Zone 5 | Northeast, Midwest: NYC, Chicago | R-49 | 16-19 in |
| Zone 6 | Northern states: Minneapolis, Buffalo | R-49 | 16-19 in |
| Zone 7 | Alaska, northern MN, high altitude | R-60 | 20-24 in |
Source: DOE Insulation Fact Sheet + IECC 2024. For your exact zone by zip code, visit energystar.gov.
DIY vs Hiring a Pro for Attic Insulation
Blown-in fiberglass, cellulose, and fiberglass batts are all realistic DIY jobs. Spray foam is not - it takes certified equipment and full PPE. Here is how the costs stack up for a typical 1,000 sq ft attic.
| Factor | DIY | Hire a pro |
|---|---|---|
| Material cost | $0.50-$1.50/sq ft (retail bags) | $0.50-$1.80/sq ft (contractor pricing) |
| Equipment | Blower rental $50-$100/day (Home Depot, Lowe's) | Included - pro brings own equipment |
| Labor | Your time (2 people, 4-8 hrs for 1,000 sq ft) | $0.80-$1.80/sq ft installed |
| Total 1,000 sq ft | $600-$1,200 (material + rental) | $1,500-$3,500 (turnkey) |
| Best for | Batt and blown-in fiberglass/cellulose in open attics | Spray foam (always), complex attics, air sealing |
Blower machine rentals from Home Depot and Lowe's run $50 to $100 per day with a deposit. The machine is free at some retailers when you buy 20+ bags of insulation.
How Much Does Attic Insulation Save?
The headline number: upgrading an under-insulated attic to DOE-recommended R-values saves 15 to 20 percent on heating and cooling bills, per ENERGY STAR and Department of Energy data. On a $2,000 annual bill, that is $300 to $400 back every year.
Why the attic matters most: hot air rises, so a poorly insulated attic is where a home loses the most conditioned air - up to 25% of heat in winter escapes through the roof. Topping up from R-19 (common in pre-2000 homes) to R-49 is the single highest-ROI insulation upgrade for most houses.
Payback timeline: a typical $1,500 to $3,500 blown-in job pays back in 5 to 10 years. Cold climates with high energy rates pay back fastest (sometimes under 4 years). The comfort improvement - fewer drafts, quieter rooms, even temperatures - is immediate and not captured in the dollar math.
The multiplier: air sealing before insulating adds another 10% in savings. Insulation slows heat flow but does not stop air movement - caulk and foam around plumbing stacks, electrical penetrations, and the attic hatch first. Most pros bundle air sealing with installation for $250 to $750.
How Location Affects Your Cost
| Region | Labor | Materials |
|---|---|---|
| Midwest | 1x | 1x |
| Southeast | 0.9x | 0.95x |
| Southwest | 1.05x | 1.1x |
| Northeast | 1.3x | 1.2x |
| West Coast | 1.4x | 1.25x |
To adjust: multiply the calculator's total by your region's average multiplier. Source: Remodeling Magazine 2026 Cost vs Value Report regional indexing + HomeAdvisor 2026 Regional Cost Index.
Red Flags in Contractor Quotes
We've reviewed hundreds of quotes. These are the warning signs that a contractor may cut corners or overcharge:
- Quote that skips air sealing - insulation without air sealing loses 30-50% of effective R-value
- Blown-in cellulose installed without baffles at soffit vents - blocks ventilation and rots the roof deck
- Fiberglass batts compressed to fit cavities - loses up to 50% of rated R-value
- Spray foam quote without mentioning ventilation and cure-time off-gassing requirements
- R-13 or R-19 left in a Zone 5+ attic - well below code minimum R-49, fails inspection
Insulation contractor? Bid attic jobs in minutes.
JobTread turns attic measurements and climate zone R-values into material orders and client-ready proposals. On a 2,000 sq ft blow-in job, it calculates bags, labor, and energy savings in 3 minutes - versus 20 by hand - and flags code minimums you might miss.
Affiliate link — we may earn a commission if you sign up.
Try JobTread FreeFrequently Asked Questions
How much does attic insulation cost in 2026?
Attic insulation costs $1,700 to $2,500 on average, or about $1 to $3 per square foot, according to 2026 Angi data. A 1,000 sq ft attic runs $1,000 to $3,000 installed. Blown-in fiberglass and cellulose are the most affordable at $0.50 to $1.80 per square foot for materials, while closed-cell spray foam runs $2 to $5 per square foot. Labor adds $0.80 to $3.00 per square foot depending on the material and attic complexity.
How much blown-in insulation do I need for my attic?
Blown-in insulation is sold in bags, and you need roughly 1 bag per 25 to 40 sq ft depending on your target R-value. For R-49 (Zones 4 through 6), expect 26 to 32 bags per 1,000 sq ft. The calculator above works out the exact bag count from your attic size, climate zone, and material. A 1,000 sq ft attic in Zone 5 typically needs 25 to 35 bags of cellulose or 20 to 25 bags of fiberglass.
What R-value do I need for my attic?
The Department of Energy recommends R-30 for Zone 1 (Florida, Hawaii), R-38 for Zones 2 to 3 (southern US), R-49 for Zones 4 to 6 (most of the country), and R-60 for Zone 7 (Alaska, far north). Higher R-values mean thicker insulation - R-49 needs about 14 to 16 inches of blown-in cellulose but only 7.5 inches of closed-cell spray foam. Pick your climate zone above and the calculator auto-fills the DOE recommendation; override it manually if your local code requires more.
Is blown-in or batt insulation better for an attic?
Blown-in wins for most existing attics because it fills gaps around joists, wiring, and irregular spaces that batts cannot seal. Blown-in cellulose runs $0.50 to $1.30 per sq ft and blown-in fiberglass $0.40 to $0.85 per sq ft. Batts ($0.40 to $1.00 per sq ft) are cheaper and true DIY, but gaps and compression can cut their effective R-value by up to 30%. Choose batts for unfinished attics with standard 16 or 24 inch joist spacing; choose blown-in for retrofits and irregular framing.
How much does it cost to remove old attic insulation?
Removing old insulation costs $1.00 to $1.50 per square foot, or about $900 added to a typical project, per 2026 Angi data. Removal is necessary if the existing insulation is wet, moldy, pest-contaminated, or contains vermiculite (an asbestos risk). If your existing insulation is dry and intact, you can usually blow new material right on top - saving the removal cost entirely. Always inspect before deciding.
How much energy does attic insulation save?
Upgrading an under-insulated attic to DOE-recommended R-values typically saves 15 to 20 percent on heating and cooling bills, according to ENERGY STAR and Department of Energy data. If you spend $2,000 a year on heating and cooling, that is $300 to $400 in annual savings. The calculator shows your estimated payback period - most attic insulation jobs pay back in 5 to 10 years, faster in cold climates with high energy rates. Air sealing before insulating can add another 10 percent in savings.
Can I install attic insulation myself?
Yes for fiberglass batts and blown-in fiberglass or cellulose - Home Depot and Lowe's rent blow-in machines for $50 to $100 per day. A 1,000 sq ft attic is a 2-person weekend job costing $600 to $1,200 in materials and rental. DIY makes sense for open, accessible attics. Hire a pro for spray foam (which requires certified equipment and PPE), attics with knob-and-tube wiring, mold or asbestos, or when air sealing is needed. Pros charge $1,500 to $3,500 turnkey for a typical attic.
Should I choose spray foam or blown-in for my attic?
Closed-cell spray foam ($2 to $5 per sq ft) gives the highest R-value per inch (R-6.5) and doubles as an air and moisture barrier - ideal for conditioned attics, wet climates, or when you want to maximize headroom. But it costs 3 to 5 times more than blown-in. Blown-in cellulose or fiberglass ($0.40 to $1.30 per sq ft) is the value pick for vented attics. For most homeowners on a budget, blown-in to R-49 hits the sweet spot; spray foam pays off only if you are finishing the attic or fighting moisture. For a board-foot breakdown of foam pricing, use our spray foam insulation cost calculator.
Real Project Example
Attic Top-Up - R-19 to R-49 Blown-In Cellulose
Columbus, OH · 2026
Topped up a 1,400 sq ft attic in a 1990s build from R-19 to current code R-49 with borate-treated cellulose, plus air sealing.
How It Went Down
Air sealing
Caulked all top-plate penetrations and sealed around recessed lights and plumbing stacks
Air sealing first is non-negotiable - cellulose slows air but does not stop it. This step alone saved an estimated $180/yr
Baffles and rulers
Installed cardboard baffles at every rafter bay to keep soffit vents clear, plus depth rulers every 100 sq ft
Without baffles, cellulose drifts into soffits and chokes attic ventilation - a common cause of winter ice dams
Blow-in
Two-person crew layered 14 inches of cellulose to R-49, overblowing by 1.5 inches to account for settling
Cellulose settles 10-20% in the first year. We overblew so the settled depth still hits R-49 at inspection
Final inspection
City inspector verified R-value by measuring depth at the rulers; homeowner documented pre/post utility bills
Heating bill dropped from $220/mo to $168/mo in January - a 24% cut. Payback on the $2,650 job: about 5 years
What we learned: Air sealing the attic floor before blowing in cellulose delivered a 24% heating bill reduction - bigger than the insulation alone would have. The $300 spent on caulking and foam had a faster payback than the $2,350 of cellulose on top of it. Skip air sealing and you lose a third of the benefit.
EstimatorSuite contractor interviews, 2026
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Focused on spray foam only - board feet, open vs closed cell, per-board-foot pricing. Use it when you have already decided on foam.
Insulation R-Value Calculator →
Tells you what R-value you need by climate zone and application (attic, wall, floor, basement) - without the cost math. Use it first to pick a target.
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All CalculatorsMarcus Webb
Lead Reviewer & Construction Tech Analyst
Marcus spent 8 years working with general contractors and trade businesses before focusing on construction technology. He has personally tested 30+ estimating and project management tools with real project data.
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