That's our range to add blown-in insulation to an attic floor, installed, with a typical price of about $1.90 per square foot. A 1,000 sq ft attic typically costs about $1,900. Batts run about $1.50 per sq ft and spray foam about $3. Removing old insulation and air sealing add to that if they aren't in the quote.
Estimate Our range, based on sources [1][2][3][4]. Planning numbers, not quotes. The R-value you need, attic access and prep work move the price most.
Bars run from our Low to High figure; the dark tick marks Typical. Same numbers as the table below.
Attic insulation cost by type
Blown-in insulation is the usual choice for an attic floor because it fills gaps around joists, wires and odd corners. Batts suit open, regular framing. Spray foam costs the most and is mainly used to seal and insulate the underside of the roof.
| Type | Our range Estimate | Typical Estimate | What the sources publish Sourced |
|---|---|---|---|
| Blown-in (loose-fill fiberglass or cellulose) | $1.65 – $2.80 | $1.90 | HomeGuide attic blown-in $0.90 – $2.40, all blown-in $1 – $2.80; Angi blown-in, 1,000 sq ft $1,750 – $7,500[1][2][4] |
| Fiberglass batts or rolls | $0.80 – $1.70 | $1.50 | HomeGuide attic batts $0.80 – $2.60, all batts $0.80 – $2.60; Angi fiberglass batts $0.30 – $1.50[1][2][3] |
| Spray foam (open- or closed-cell) | $1.80 – $4.20 | $3 | HomeGuide attic spray foam $1 – $4.50, all spray foam $1.50 – $5[1][2] |
Estimate Our range, based on sources [1][2][3][4]. For each tier we pooled the low, midpoint and high figure each source publishes for a comparable scope (a single benchmark figure counts once), then used the median as Typical and the middle half of the pooled figures as Low–High. Angi publishes blown-in insulation by attic size, so we divided its 1,000 sq ft price by 1,000. Spray foam draws on HomeGuide only, because Angi prices it per board foot. See How we build our ranges.
What the sources say Sourced
HomeGuide puts attic insulation at $1 – $4 per sq ft installed, or $1,000 – $2,700 for a typical attic (average $1,800).[1] Angi's national average for insulation jobs is $1,860 from 7,605 projects, with most between $1,071 – $2,650, and it puts attics at $1 – $7 per sq ft.[3] Angi's average blown-in job is $1,660, most between $987 – $2,334.[4]
Blown-in attic insulation cost by attic size Estimate
| Attic floor | Our range Estimate | Typical Estimate | HomeGuide, any type Sourced |
|---|---|---|---|
| 500 sq ft attic | $850 – $1,400 | $950 | $500 – $2,000 |
| 700 sq ft attic | $1,150 – $1,950 | $1,350 | $700 – $2,800 |
| 1,000 sq ft attic | $1,650 – $2,800 | $1,900 | $1,000 – $4,000 |
| 1,200 sq ft attic | $2,000 – $3,350 | $2,300 | $1,200 – $4,800 |
| 1,500 sq ft attic | $2,500 – $4,200 | $2,850 | $1,500 – $6,000 |
| 2,000 sq ft attic | $3,300 – $5,600 | $3,800 | $2,000 – $8,000 |
Estimate Our blown-in blend multiplied by the attic floor area. Small jobs can cost more per square foot because some companies have a $1,500 – $2,000 minimum.[1]
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Extra costs to check for in your quote
| Item | Cost | Basis |
|---|---|---|
| Remove old insulation | $1 – $2 per sq ft Sourced | HomeGuide; needed if it's wet, moldy, pest-damaged or hazardous[1] |
| Air sealing the attic floor | $500 – $1,650 Estimate | Blend of HomeGuide $350 – $3,000 and Angi $300 – $1,500[1][4] |
| Soffit vent baffles | $2 – $3 each Sourced | HomeGuide; keeps insulation from blocking airflow[1] |
| Venting a bath or kitchen fan outdoors | $200 – $700 Sourced | HomeGuide; fans that exhaust into the attic must be vented out first[1] |
| Site prep and cleanup | $150 – $900 Sourced | Angi: removal, drywall repair, debris disposal[3] |
| Pest inspection | $40 – $150 Sourced | HomeGuide[1] |
| Minimum job charge | $1,500 – $2,000 Sourced | HomeGuide: some insulation companies have one[1] |
HomeGuide puts insulation labor at $0.50 – $1.30 per sq ft, and replacing old attic insulation outright at $2 – $6 per sq ft including removal.[1] Sourced
What drives the price
- R-value and climate. The Department of Energy recommends roughly R-30 to R-60 in attics depending on the climate zone, so colder places need thicker insulation.[1] Our local cost pages list each metro's climate zone.
- Adding vs. replacing. Topping up existing insulation is cheaper; HomeGuide puts adding more at $1 – $4 per sq ft.[1] Wet, moldy or pest-damaged insulation has to come out first.
- Air sealing. Sealing gaps around lights, pipes and the attic hatch makes new insulation work better, and some contractors include it.[1]
- Access. Low-pitched roofs, tight crawl spaces and attics full of storage take longer.
- Where the insulation goes. Insulating the roof deck in an unvented attic covers more area than the floor and usually means spray foam: HomeGuide puts attic spray foam at $1,100 – $6,800 for the floor and $1,500 – $9,000 for the rafters and roof deck.[1]
HomeGuide says adding attic insulation saves 10% to 20% on heating and cooling.[1] Sourced Savings depend on what you have now, your climate and your energy prices.
Regional differences Estimate
| Region (Census division) | Our cost index Estimate | Typical 1,000 sq ft blown-in Estimate |
|---|---|---|
| New England CT, ME, MA, NH, RI, VT | 1.04 4% above U.S. | $2,000 |
| Middle Atlantic NJ, NY, PA | 1.13 13% above U.S. | $2,150 |
| South Atlantic DE, DC, FL, GA, MD, NC, SC, VA, WV | 0.98 2% below U.S. | $1,850 |
| U.S. average | 1.00 | $1,900 |
| East North Central IL, IN, MI, OH, WI | 0.96 4% below U.S. | $1,800 |
| East South Central AL, KY, MS, TN | 0.90 10% below U.S. | $1,700 |
| West North Central IA, KS, MN, MO, NE, ND, SD | 1.02 2% above U.S. | $1,950 |
| West South Central AR, LA, OK, TX | 0.89 11% below U.S. | $1,700 |
| Mountain AZ, CO, ID, MT, NV, NM, UT, WY | 0.96 4% below U.S. | $1,800 |
| Pacific AK, CA, HI, OR, WA | 1.07 7% above U.S. | $2,050 |
Estimate Derived, not published. Our interior index divides each division's 2025 Cost vs. Value average for four interior projects (three bathroom remodels and a basement remodel) by the national average and averages the four ratios.[5] The typical column multiplies our national typical by the index. See How we build our ranges.
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Get it freeCosts in your city
Our local cost pages adjust these national ranges for 50 metro areas using local construction wages, and add each area's housing age, climate zone and permit office: Atlanta, Austin, Baltimore, Birmingham, Boston, Charlotte, Chicago, Cincinnati, Cleveland, Columbus, Dallas, Denver, Detroit, Fresno, Grand Rapids, Hartford, Houston, Indianapolis, Jacksonville, Kansas City, Las Vegas, Los Angeles, Louisville, Memphis, Miami, Milwaukee, Minneapolis, Nashville, New York, Oklahoma City, Orlando, Philadelphia, Phoenix, Pittsburgh, Portland, Providence, Raleigh, Richmond, Riverside, Sacramento, Salt Lake City, San Antonio, San Diego, San Francisco, San Jose, Seattle, St. Louis, Tampa, Virginia Beach, Washington. See all local costs →
Attic insulation FAQ
How much does it cost to insulate a 1,000 sq ft attic?
Typically about $1,900 with blown-in insulation by our estimate ($1,650 – $2,800). HomeGuide puts a 1,000 sq ft attic at $1,000 – $4,000 for any type, and Angi puts blown-in at $1,750 – $7,500.[1][4]
Is blown-in or batt insulation cheaper for an attic?
Batts can be a little cheaper per square foot (typically about $1.50 vs. $1.90 by our blend), but blown-in fills gaps around joists and wiring better, so it's the usual choice for attic floors.[1][2][3][4]
How much does spray foam attic insulation cost?
About $1.80 – $4.20 per sq ft by our blend of HomeGuide's figures, typically $3. HomeGuide puts attic spray foam at $1,100 – $6,800 for the floor and $1,500 – $9,000 for the roof deck.[1][2]
Do I need to remove old insulation first?
Only if it's wet, moldy, damaged by pests or fire, or a hazardous material. Otherwise new insulation can usually go on top. HomeGuide puts removal at $1 – $2 per sq ft.[1]
Is adding attic insulation worth it?
Often, in an under-insulated attic. HomeGuide says it saves 10% to 20% on heating and cooling.[1] Check for rebates or tax credits that apply to insulation and air sealing before you hire.
Related cost guides
Sources
- HomeGuide, “How much does attic insulation cost?” (updated Jan 13, 2026). homeguide.com/costs/attic-insulation-cost (accessed Oct 14, 2026).
- HomeGuide, “How much does insulation cost?” (updated Dec 19, 2025). homeguide.com/costs/insulation-cost (accessed Oct 14, 2026).
- Angi, “How Much Does Insulation Installation Cost? [2026 Data]” (updated Oct 6, 2026). angi.com/articles/how-much-does-insulation-cost.htm (accessed Oct 14, 2026).
- Angi, “How Much Does Blown-In Insulation Cost? [2026 Data]” (updated Sep 23, 2026). angi.com/articles/blown-in-insulation-cost.htm (accessed Oct 14, 2026).
- Zonda / Journal of Light Construction, 2025 Cost vs. Value Report: national averages and regional pages (New England, Middle Atlantic, South Atlantic, East North Central, East South Central, West North Central, West South Central, Mountain, Pacific) (accessed Oct 8, 2026). © 2025 Zonda Media. We quote a few national figures and use the regional figures only to derive our own cost index. States per division from the U.S. Census Bureau, Census Regions and Divisions.
Quoted figures are labeled Sourced. Everything labeled Estimate is our own arithmetic on these sources, explained in How we build our ranges. Planning numbers only, not quotes. Get itemized local bids before you commit.