How Much Does Insulation Cost?

Insulation costs between $1,400 and $6,300. Blown-in insulation costs a little less than batting, fiberglass and radiant barrier insulation, at $2,900 on average. Spray foam insulation is the most expensive option but has the highest ROI. You’ll spend between $0.25 and $2 for every inch of thickness per square foot (one board foot) or $1 to $5 per square foot total.

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$1,645 Average National Cost
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Install Batt, Rolled, or Reflective Insulation
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$1,846 Average National Cost
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$5,196 Average National Cost
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$5,047 Average National Cost
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Over the life of your home, you’ll usually make back everything you spend on insulation, sometimes in only a few years. With an ROI of 100% or more, it’s one of the best investments in both new construction and older homes. Insulation helps keep your home cool in the summer and warm in the winter by slowing down the transfer of heat through your floors, walls and ceiling. Read more below on the different types and costs of home insulation.

Insulation Cost Per Square Foot

The following table shows the cost per board foot, which is 1 square foot by 1 inch thick. So, 1 square foot that is 6 inches thick would be 6 board feet. For your price range, simply multiply the prices listed below by the thickness you need. Each inch of insulation provides between a 3 and an 8 R-value. R-value rates how well the material insulates, the higher the value, the better the insulation.

TypeMaterial Price Per Board Foot
Batting$0.30 – $1.50
Blown-in$1 – $2
Spray Foam$0.50 – $2
Radiant$0.20 – $1
Rigid$0.25 – $1

Fiberglass Insulation Cost

Fiberglass batt insulation costs $1,000 to $2,400. The average cost per square foot is between $0.30 to $1.50. So, for a 500-square-foot area, your estimate will vary between $150 to $700 if you do it yourself. For a professional job, add $200 to $500 for labor, and you're looking at around $350 to $1,000 for 6 hours of work. When installed tightly and securely, fiberglass batts improve energy efficiency by 25 to 30%.

Cost of Cavity Wall Insulation

Filling a wall cavity costs $1 to $2 per square foot on average. You’ll typically fill the space with blown-in fiberglass, but in some cases, you can use spray foam. Since most homeowners are seeking to insulate previously built structures with drywall, blown-in insulation works best in the interior.

Blown-In Insulation

Blown-in insulation costs $1,000 to $2,100 on average. Typically installed in attics, loose-fill insulation is also sometimes used to backfill wall cavities. Made from white cellulose, you can find reclaimed and recycled varieties. For DIY projects, you can purchase bags of it at a home improvement store and rent a blower for under $100 a day. Total DIY costs run $500 or less.

Reflective or Radiant Barrier

Radiant barrier insulation costs $700 to $2,900 on average. Materials alone run $0.25 to $1 per square foot, depending on the thickness and brand. To cover a typical 500-square-foot attic, you'll likely spend $125 to $500, with double-sided barriers being slightly more expensive. To pay for a professional installation, add $575 to $750 to that cost.

Foam and Rigid Insulation Pricing

At $0.25 to $2 per board foot, open and closed cell foam are some of the most expensive types of insulation, but at a rating of up to R8 per inch of thickness, they’re also some of the best insulators on the market. Spray foam does an exceedingly good job of creating an almost airtight thermal barrier. Rigid installations make up all types of foam boards and structurally insulated panels (SIPs). When installed properly, it’s excellent for all applications, from floors and walls to ceilings and roofs.

Foam Insulation Prices Per Board Foot

TypePrice Per Board Foot
Polyiso$0.40 – $0.60
EPS$0.25 – $0.35
XPS$0.40 – $0.50
SIPs$7 - $12*
SPF$0.50 – $1

*SIPs come as a complete unit of around 4-inch thick insulation between plywood or OSB, so this price covers the whole thing, not just one inch thick of insulation.

Note that all foam types are sold and rated by the board foot, which is 1 square foot of material 1 inch thick. You can generally purchase rigid materials in thicknesses up to 4 inches.

Polyiso Insulation Price

Polyisocyanurate insulation costs $0.40 to $0.60 per board foot (1 square foot, 1 inch thick). Commonly used for flat roof installations in commercial projects, such as office buildings and apartments, it comes in thicknesses of 1 to 4 inches. Each inch has an R-value of about 8. That means a 4-inch-thick board costs $1.60 to $2.40 per square foot with an R-value of 32.

Expanded Polystyrene (EPS)

EPS costs $0.25 to $0.35 per board foot. Its R-value is about a 4, a full point less than EPS and half as much as Polyiso, but at nearly half the cost of either of the other varieties, it has the highest insulation to cost ratio.

Extruded Polystyrene (XPS)

XPS costs $0.40 to $0.50 per board foot. It averages an R-value of 5 at nearly twice the price of EPS, but it’s a better option for those looking to save space.

Structural Insulated Panel Cost (SIPs)

The closed-cell insulation cost of a SIPs panel runs $7 to $12 per square foot. A SIPs panel is essentially a thick piece of rigid foam board between two sheets of plywood or OSB and designed to carry weight. They’re made in a factory and shipped to the job site. They replace conventional stick framing for the walls and roofs.

Spray Foam Insulation (SPF)

Spray foam insulation costs $0.50 to $2 per board foot depending on if you choose to seal leaks and gaps inside existing walls. This insulation is the perfect solution for those who are looking for a relatively inexpensive way to fix a larger problem, while increasing their home's R-value. When done properly, spray foam can save you $500 or more a year in energy costs.

  • Open-cell spray foam is generally $0.35$0.55 per board foot

  • Closed-cell spray foam is generally $1$2 per board foot

Not all professionals offer this specialized service. Although more expensive initially, it’ll save you more in the long run. Discuss options with a local spray foam installer.

Home Insulation Costs

Home SpaceCost
Garage$0.50 – $1.25 per sq. ft.
Crawl Space or Floor$1 – $5 per sq. ft.
Basement$1.50 – $2.50 per sq. ft.
Attic$1,500 – $6,000 total
Roof$1,500 – $4,500 total
Wall$1 – $4 per sq. ft.

Cost to Insulate Garage

It’ll cost $0.50 to $1.25 per square foot to insulate a garage. A professional installation may double that price, which doesn’t include the garage door. The total price ranges from $1,500 to $8,000 depending on the materials you choose and the size of the space.

Attached garages only need the outside walls insulated, not anything connected to the main home. Insulating a garage door with rigid foam or batts costs about $200 to $300 for a 9-foot-tall door.

Floor and Crawl Space Insulation Cost

Crawl space insulation costs $1 to $5 per square foot, depending on the type of material used. You’ll usually spend $500 to $1,500. You can either insulate the ceiling of the crawlspace (the interior floor) or the walls around the sides.

The most common materials include fiberglass, rigid board and spray foam. For new construction, consider using insulated concrete forms which cost $150 to $160 per square foot, but that cost includes the poured concrete wall.

Cost to Insulate Basement

Insulating a basement costs $1.50 to $2.50 per square foot. Most basements don’t need nearly as much insulation as upper floors since the surrounding earth helps to keep the space warm in the winter and cool in the summer.

Attic Insulation

Insulating an attic costs $1,500 to $6,000, depending on the materials you use. More commonly, spray foam gets laid first, then covered with batts or blown in. Since heat rises, it’s one of the most important parts of your home to insulate. Most homes have at least twice as much insulation in the attic as they do in the walls.

Roof Insulation

Insulating your roof costs anywhere from $1,500 to $4,500 or more. This creates a conditioned space that you can then convert into a living space. Most attic conversions cost $40,000 and you can often bundle the price in with new roofing.

You can insulate a roof during or after construction. During new construction, a pro can put layers of rigid foam board on the sheathing but beneath the shingles. You can also have spray foam or batting placed inside the attic along the rafters.

Wall Insulation Cost

Wall insulation costs $1 to $4 per square foot. Most batting—both mineral wool and fiberglass—costs $1 to $1.50 per square foot to install. Some new construction homes use rigid, reflective, spray foam or a combination of all of them, which might run $3 to $4 per square foot.

You can also build a home’s walls using insulated concrete forms, where rigid foam works as the concrete form, which remains in place after construction.

Pole Barn Insulation Cost

You’ll pay $1 to $4 per square foot to insulate a pole barn. Professionals recommend either fiberglass batting with a thick polypropylene sheet covering it or spray foam. Spray foam, while more expensive, does a better job of stopping air leaks. To keep prices down, you can do a thinner layer of spray foam covered with fiberglass batting.

Cost to Insulate a Mobile Home

Insulating a mobile home costs $0.25 to $1 per square foot for fiberglass batting but can hit up to $3 per square foot when using thicker materials and with professional installation.

Insulation Replacement Cost

Replacing insulation costs $2 to $7 per square foot for most blown in and fiberglass. Spray foam insulation isn’t completely removable, while rigid foam boards are usually the easiest to take out of your home.

Once removed, a professional patches and seals up the area and fills it in with whatever type you choose. Over time, most insulation loses some of its R-value.

Insulation Removal Cost

Removing insulation costs $1 to $1.50 per square foot, not including any disposal fees. Removing batts takes less time than other types since it’s only set in place. Blown-in attic insulation removal may use either a large vacuum or manual removal using large bags.

Labor Cost to Install Insulation

Labor to install most insulation runs $0.25 to $0.50 per square foot. However, it depends on the type you’re putting in. For example, spray foam takes more prep and experience to correctly install versus something like batt insulation, which goes in quickly with almost no experience necessary.

DIY vs. Hire Insulation Contractor

Most insulation projects are DIY friendly, with the only drawbacks being time and mess. For the best DIY solutions, try fiberglass roll and batting or rigid foam boards.

However, you’ll want to carefully install the products to fill all cracks without compressing any of the fiberglass. The value of the insulation comes from its ability to create air pockets between the fibers; once compressed, they lose a lot of their insulation properties. You’ll also want to wear proper protective gear, including a dust mask, goggles, gloves and full-coverage clothing.

If you prefer to have anything spray foamed or want to make sure you get all the R-value you can out of the project, you’ll always get your best results from a local insulation contractor. You’ll also want to consult a pro for any blown-in attic jobs and roof work, as those require specialized skills and equipment.


What does R-value mean?

Basically, it represents how well the insulation slows down the transfer of heat. The higher the R-value, the better the insulation, the slower you lose heat in the winter or gain heat in the summer. R-value usually degrades over time by up to half.

What rebates or savings are available for insulating your home?

You can often find both local and federal rebates for insulation. Find an insulation professional to discuss what rebates are available in your area.