Attic Insulation Cost: Price per Sq Ft by Material
Attic insulation cost runs about $1 to $3 per square foot for most blown-in jobs, and a typical 1,000-square-foot attic costs $1,500 to $3,000 installed, according to Block Renovation. Spray foam costs more. Material, existing insulation, and air sealing decide your price. In Minnesota, the goal is a total of R-49 to R-60 in the attic.
Reviewed by the Three Rivers Contracting project team · MN Residential Building Contractor BC760638
Attic insulation cost per square foot by material
| Material | Installed cost per sq ft | Notes |
|---|---|---|
| Fiberglass batts | $0.80 to $2.50 | Cheapest; gaps and compression reduce performance |
| Blown-in fiberglass | $1.00 to $2.50 | Fills irregular spaces; common choice |
| Blown-in cellulose | $1.20 to $3.00 | Dense, recycled paper product; good air resistance |
| Spray foam | $1.50 to $5.00 | Highest cost; seals air as well as insulating |
Source: Block Renovation's 2026 guide. Other sources, like ThePricer, report a wider $1.50 to $5.50 installed range, and $4 to $10 per square foot for roof-deck spray foam. The differences come from varying R-values, access, and what is included. Treat all of these as ranges, not quotes.
Total cost by attic size
| Attic size | Typical total |
|---|---|
| 500 sq ft | $800 to $1,500 |
| 1,000 sq ft | $1,500 to $3,000 |
| 1,500 sq ft | $2,000 to $4,500 |
| 2,000 sq ft | $3,000 to $7,000 |
Those totals include some air sealing. Many Twin Cities ranch and two-story homes have 800 to 1,500 square feet of attic floor, so expect to land in the low-to-mid thousands.
What changes the price
- Air sealing: Block Renovation says air sealing alone adds $200 to $1,500, depending on how many gaps there are and how hard they are to reach. It is often the best-value part of the job.
- Removal of old insulation: about $1 to $2 per square foot, plus disposal. This is needed if insulation is wet, moldy, or contaminated.
- Access and layout: tight attics, knee walls, and low roof pitches take longer.
- Target R-value: more depth uses more material.
- Obstacles: recessed lights, bath fans, and chimneys need baffles or barriers.
- Ventilation: baffles at the eaves keep airflow open. See roof ventilation basics for Minnesota attics.
Minnesota R-value targets
Cold-climate guidance for northern states is typically R-49 to R-60 in the attic. Block Renovation lists R-49 to R-60 for cold northern climates. In blown fiberglass or cellulose, that takes well over a foot of depth, and the exact number of inches depends on the product. Check the manufacturer's coverage chart, because depth and R-value vary by material. Our attic insulation R-values and rebates guide goes deeper, and signs your home is under-insulated will help you decide whether you need it.
Rebates and incentives
The federal 25C credit for insulation ended for property placed in service after December 31, 2025, so do not plan around it. Utility programs may still help. For example, the City of Hastings lists a CenterPoint Energy rebate for air sealing and insulation upgrades, and Xcel Energy also runs home energy programs. Rebate amounts and eligibility change often, so confirm current details with your utility before you start. Some programs require work to be done before a rebate application is filed, or require specific materials.
Payback and what to expect
Payback depends on your heating fuel, how much insulation you have now, and how leaky the ceiling is. Adding insulation to a thinly insulated attic usually delivers the biggest gain per dollar of any envelope upgrade. If your attic already has about 12 inches of fiberglass, topping it up costs less and delivers less improvement. Beyond savings, insulation and air sealing reduce ice dams and make rooms under the roof more comfortable year round.
Blown-in vs. spray foam vs. batts
Blown-in fiberglass or cellulose over a sealed attic floor is the most cost-effective choice for most open attics. Batts are fine for small, regular spaces if cut and fit carefully. Spray foam makes sense in cathedral ceilings, rim areas, and spots where air sealing and insulation need to happen at once, but it is much more expensive over a whole attic and should be installed by trained crews.
Questions to ask before you hire
- What R-value and how many inches will be installed, and how will depth be verified?
- Is air sealing included, and what will be sealed?
- How will the eaves stay ventilated, and are baffles included?
- How will recessed lights, bath fans, and the attic hatch be handled?
- Is old insulation being removed, and why?
Hiring tips
Get bids that spell out R-value, inches installed, air sealing scope, baffles, and removal. Ask for a bag count or coverage chart. Avoid any plan that blocks soffit vents or buries recessed lights without proper covers. If you are also dealing with a roof, our insulation services page shows how we bundle this work with other exterior projects.
Want a straight answer on your own house? Call (651) 565-1349 or get a free estimate from Three Rivers Contracting.
Frequently asked questions
How much does attic insulation cost per square foot?
Most installed blown-in attic insulation runs about $1 to $3 per square foot, depending on the material and the job, with fiberglass batts around $0.80 to $2.50 and spray foam $1.50 to $5. Air sealing, old insulation removal, access, and target R-value can raise the total.
How much does it cost to insulate a 1,000 square foot attic?
A typical 1,000-square-foot attic costs about $1,500 to $3,000 including some air sealing. Larger attics, removal of old material, difficult access, or spray foam can push the cost higher. Get a written bid that lists R-value and air sealing included.
What R-value do I need in a Minnesota attic?
Guidance for cold northern climates is typically R-49 to R-60. If you already have a few inches of insulation, topping up to R-49 may be enough, while a nearly empty attic is often brought to R-60. Check your contractor’s chart for inches of depth.
Is there a tax credit for attic insulation in 2026?
No. The federal 25C credit for insulation applied to property placed in service through December 31, 2025, and has ended. Check your gas and electric utility for current rebates, and confirm eligibility and program rules before buying materials or scheduling work.
Do I need air sealing before adding insulation?
Usually yes. Air leaks around light fixtures, chimneys, plumbing, and top plates send warm, moist air into the attic and cut performance. Sealing them first can add $200 to $1,500 but improves comfort and helps prevent ice dams and moisture problems.