How Much Does Spray Foam Insulation Cost? [2025 Data]
The average professional spray foam insulation cost is $2,886. Prices vary with the type and size of the space. You can expect to pay between $1,454 and $4,336 for most spray foam insulation projects.
The average cost to install spray foam insulation is $2,886. Most homeowners pay between $1,454 and $4,336, or $0.60 to $3.10 per board foot. Factors affecting your spray foam insulation cost are the type you use, where in your home you install it, and the size of the space. You could spend as little as $675 for a small HVAC project or as much as $8,000 to insulate a whole home.
Spray foam insulation is mold- and mildew-resistant and highly effective in insulating your space. Although you may have to pay a high initial cost, homeowners can save significantly on utility bills after installing this light yet durable air barrier.
Spray Foam Insulation Cost Factors
Spray foam insulation costs depend on the foam type you use, insulation thickness, and more.
Open-Cell vs. Closed-Cell Foam
Open-cell and closed-cell spray foams have different structures and purposes, which also impact the cost. Open-cell foam has tiny air pockets, making it softer and more flexible. Because of its lower density, it expands more, meaning it can fill large spaces with less material. Open-cell spray foam costs about $0.60 to $1.60 per board foot installed.
Meanwhile, closed-cell spray foam is much denser and rigid. This makes it more resistant to water and air leaks. Because it uses more material and is denser, it tends to be more expensive than open-cell foam—about $1.30 to $3.10 per board foot installed.
| Spray Foam Factor | Open-Cell Spray Foam | Closed-Cell Spray Foam |
|---|---|---|
| Cost installed, per board foot | $0.60–$1.60 | $1.30–$3.10 |
| Best for | Hard-to-reach nooks and crannies and above-grade walls | Attics, crawl spaces, and basements |
| Expansion | Expands up to 3 inches to fill cracks | Does not expand more than 1 inch |
| R-value per inch | Lower R-value at 3.5 to 3.7 | Higher R-value at 5 to 7 |
| Flexibility | Soft and flexible | Rigid and dense |
| Protects against moisture | Somewhat | Moisture-resistant |
| Sound reducing | Somewhat | Best option |
Spray Foam Insulation Thickness
Insulation is measured by a figure called an R-value. Higher R-value insulations are more effective at thermal resistance—especially when layered. Open-cell spray foams have an R-value of 3.5 to 3.6 per inch, while closed-cell foams have an R-value of 6 to 7 per inch. The higher the R-value and the thicker the layer, the more you’ll pay for the cost of spray insulation.
| Spray Foam Thickness | R-Value for Open Cell | R-Value for Close Cell |
|---|---|---|
| 1 inch | 3.5–3.6 | 6–7 |
| 2 inches | 7.0–7.2 | 12–14 |
| 3 inches | 10.5–10.8 | 18–21 |
Size of the Area
The cost to install insulation in a larger area is higher than that in a smaller area, since you’ll need more material. When considering the square footage of your area that needs spray foam insulation, you can expect to pay between $1.00 and $5.00 per square foot on average.
| Area Size, Square Feet | Average Cost, Installed |
|---|---|
| 100 | $100–$500 |
| 200 | $200–$1,000 |
| 300 | $300–$1,500 |
| 500 | $500–$2,500 |
| 1,000 | $1,000–$5,000 |
| 1,500 | $1,500–$7,500 |
| 2,000 | $2,000–$10,000 |
| 2,500 | $2,500–$12,500 |
| 3,000 | $3,000–$15,000 |
Spray Foam Insulation Type
There are various types of insulation made from different materials. These materials can change the cost of the spray foam.
Polyurethane is the most common type of spray foam because of its price value and insulating capabilities. According to the U.S. Environmental Protection Agency (EPA), while polyurethane spray foam is usually considered inert, it does have the potential to off-gas VOCs (volatile organic compounds) for the first few years after installation.
Some alternatives that are more eco-conscious and made from renewable oils include soybean spray foam, vegetable oil spray foam, and water-based spray foam. Here’s what each costs.
| Insulation Type | Average Cost, Per Board Foot | Best For |
|---|---|---|
| Polyurethane spray foam | $0.44–$1.50 | Attics, basements, and home exteriors |
| Soybean spray foam | $1.50–$3.00 | Attics, walls, and basements |
| Vegetable oil spray foam | $1.50–$3.00 | Walls, roofs, attics, and floors |
| Water-based spray foam | $0.50–$2.50 | Attics, walls, crawl spaces, and ceilings |
Labor
Both materials and labor make up the total cost of spray foam insulation that you pay. Most local insulation contractors will charge between $50 and $100 an hour for this job, which makes up the bulk of the overall cost. Some contractors charge their labor by the square footage at a rate of $0.44 to $3.30, not by the hour, so it's best to have a conversation with your pro ahead of time to understand exactly how you’ll be charged.
New Construction vs. Existing
It costs less per square foot to install spray foam insulation in a new construction than it does in existing construction. This is because existing construction requires extra work—like tearing open walls, removing old insulation, and installing new drywall—which drives up labor costs.
| Type of Installation | Average Cost, Per Square Foot |
|---|---|
| New build | $1–$4 |
| Existing home | $3–$5 |
Removing Old Insulation
Planning on replacing existing insulation? If you’re wondering if you should remove your old insulation first, the answer is almost always yes. The old stuff can harbor mold, allergens, and rodent excrement (gag). If you’re having a pro remove it for you, this might result in additional fees. For instance, the cost of junk removal averages $240.
If removing old fiberglass insulation on your own, take the proper safety precautions, such as wearing long sleeves, goggles, and a face mask. Fiberglass is dangerous when inhaled or when it comes into contact with your eyes and skin.
Vapor Barrier Installation Costs
Insulating your home with closed-cell spray foam can create a tight air barrier, but open-cell spray foam does not act as a vapor barrier (also called a vapor retarder). Thus, you may need to install a vapor barrier when you use open-cell foam insulation; this slows the rate at which moisture will move through your home.
You can expect to pay between $0.65 to $1 per square foot to install a vapor barrier.
Think you can handle this work on your own? Check out our guide on how to install a vapor barrier without calling a pro.
Mold Remediation
If your old insulation has mold, you’ll need to hire a local mold remediation company to safely remove the old insulation before a pro installs new spray foam insulation. Mold typically appears from moisture—such as flooding or a leak.
You’ll want to ensure your mold remediation specialist pinpoints and repairs the cause of the mold buildup before installing new insulation. Mold remediation costs between $1,125 to $3,345.
Soundproofing
You can use spray foam insulation to soundproof a room because it absorbs acoustics. You’ll need to have spray foam injected into your walls and ceiling. Soundproofing a room costs between $1 to $3 per square foot when using this method.
Cost of Spray Foam Insulation by Location in the Home
The price of spray foam insulation varies depending on where in your home the insulation contractors are installing the material. Closed-cell spray foam is the ideal choice for these projects, as it creates an effective barrier against air and moisture.
| Location in Home | Average Cost, Installed |
|---|---|
| Basement | $1,500–$6,200 |
| Attic | $1,100–$9,000 |
| Roof | $1,500–$7,000 |
| Garage | $1,500–$9,400 |
| Crawl space | $1,200–$6,900 |
| HVAC | $1,000–$3,900 |
| Whole home | $4,000–$29,000 |
Basement: Spray foam insulation for a basement costs $500 to $3,000 per 1,000 square feet, including labor.
Attic: Insulating an attic with spray foam costs $1,100 to $9,000 on average. You should contact an attic insulation contractor near you for this expansive project.
Roof: Get in touch with a roof insulation contractor near you to tackle this type of work.
Garage: You should also insulate your garage door with weather stripping on the bottom edge and polystyrene panels on the backside.
Crawl Space: Spray-in insulation costs for a 2-by-10-foot crawl space are $1,200 to $6,900. This is often less than the cost of crawl space encapsulation but still offers some waterproofing benefits.
HVAC: HVAC insulation costs $1,000 to $3,900 for 1,000 square feet of spray foam insulation. If you’re not using duct liner insulation, spray foam is a great alternative because it can easily fit into a tight space, like around piping, and expand. It can also seal air leaks and act as a moisture barrier.
Whole Home: If you’re looking to add spray foam insulation to your whole home, you can expect to spend as little as $4,000 if you already have existing insulation or as much as $29,000 or more if your home is a new build with no existing insulation.
DIY Spray Foam Insulation vs. Hiring a Pro
Handy homeowners can purchase spray foam insulation kits that cover up to 200 to 600 square feet. These kits run between $350 to $800, and you’ll need at least two to three kits to cover that amount of square footage. Because you’re not paying for labor, DIY spray foam insulation costs less than what you’d pay the pros, but it’s not an easy project to undertake.
We recommend getting multiple quotes and hiring a spray foam insulation contractor near you—as this is a job for an experienced pro. Spray foam insulation comes with health and safety risks if you don’t follow the proper precautions when installing it. And if you already have existing insulation that you’d like to replace with spray foam insulation (which you most likely will), you’d be taking on a large project of removing drywall and the existing insulation.
Cost of Common Spray Foam Insulation Add-Ons
Many homeowners install spray foam insulation to improve their home’s heating and cooling efficiency. That’s why many choose to take on other energy-saving projects at the same time.
Window installation cost: $575–$1,475
HVAC maintenance cost: $100–$550
Air duct sealing cost: $500–$4,000
How to Save on Spray Foam Insulation Costs
Spray foam is one of the costlier types of insulation, but here’s how you can reduce the total budget of your project.
Choose Open-Cell Spray Foam: This has a lower R-value than closed-cell spray foam but costs around 50% less. However, it’s not moisture-resistant, so only use it in dry areas.
Install Spray Foam in New Construction: You can save up to $2,000 by installing spray foam in new construction or while you’re already renovating instead of later opening up the walls and replacing old insulation.
DIY Your Installation: DIY spray foam insulation if you know what you’re doing. If a shoddy job leads to a frozen pipe, you could spend thousands cleaning up the water damage.
Mix Insulation Types: Since spray foam costs more than other insulation types, you can mix it up. For example, you can install fiberglass batts in larger areas of your home and install spray foam around pipes and in nooks and crannies.
Target Key Areas First: Insulate areas that lose the most energy, like the attic or basement, instead of doing the whole house at once.
How Angi Gets Its Cost Data
Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We’ve surveyed thousands of real Angi customers about their project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects.
Want to help us improve our cost data? Send us a recent project quote to costquotes@angi.com. Quotes and personal information will not be shared publicly.
Frequently Asked Questions
Spray foam insulation doesn’t just produce a heavy chemical odor as it cures. Depending on the type, it can off-gas VOCs and trigger asthma and allergies. You and your family should steer clear for at least 24 hours—especially if your contractor is using polyurethane foam. If you’re applying spray foam DIY, make sure you wear the proper personal protective equipment (PPE).
Spray foam insulation can last up to 80 to 100 years, making your investment worthwhile over the long run. Closed-cell spray foam tends to have the highest durability. Open-cell foam is subject to moisture, which can lead to deterioration. Remember that some spray foams will damage plastic piping, so consult a pro if you have PVC or CPVC pipes.
Closed-cell spray foam insulation itself serves as a vapor barrier (or vapor retarder). However, you may need to install a vapor barrier if you have open-cell spray foam insulation. When in doubt, work with a professional insulation contractor, as they can provide more detail about the specific needs of your home in your climate.
