How Much Does Spray Foam Roofing Cost?

Average Cost to Install Spray Foam Roofing

Estimating Costs

Labor and material costs are split fairly evenly for spray foam roofing projects. You'll also need to account for removing old roof material, the cost of permits, and an allowance for any unexpected issues.

Labor

Roofers cost $2 to $4 per square foot for spray foam jobs. Plus, if you need to remove old roofing material, that'll cost an additional $1 per square foot in labor. So, for a typical 1,500-square-foot home, you'd pay $3,000 to $6,000 for a straightforward installation or, with old roof removal and foam installation, you could pay up to $4,500 to $7,500.

Materials

The materials for polyurethane foam roofing installation cost $2 to $3 per square foot, putting your total material cost at $3,000 to $4,500 for a 1,500 square-foot home.

“Many professionals consider foam roofing to be a modern approach to improving the integrity of your property,” says Eric Gonzalez, Angi Expert Review Board member and president of Regions Commercial Roofing, with locations in five states. “Installing a foam roof can be a complex process. We recommend that, if you decide to install a foam roof, you follow a proper process towards choosing a contractor. Make sure to find a contractor certified with the type of products you are installing, as this will ensure you get the most from your new roof and get the proper life term from it.”

If you need extra reinforcement and extreme insulation and durability, you can install a third layer of high-density foam and reinforce the whole roof with a silicone layer, plus a sealant. This is an additional $1.35 to $2.35 per square foot. So, for a 1,500-square-foot roof with a triple layer of high-density foam, silicone reinforcement, and an extra sealant layer, expect to pay between $8,000 and $14,000.

Permits

You can pay up to $300 for construction permits for roofing work. Whether you need a permit and how much it costs depends on your location and the type of work you're having done. Small repairs and patching under 100 square feet usually don't require a permit. However, work on areas larger than 100 square feet usually requires permits. Check with your local roofing contractor who will likely take care of all permitting issues for you.

Overages

It's always a good idea to set aside 15% to 20% of the project goal as a buffer against unforeseen problems. For example, while working on your roof, the contractor might spot water damage, rotten timber, or a pest or wildlife problem that requires immediate attention. If you've got the overage in your budget, paying for these issues won't be too much of a hardship and the spray foam installation can continue as soon as possible.

Foam Roof Installation Cost by Square Foot

Spray foam roofing costs $4 to $7 per square foot, all in. This doesn't include removing old roofing material or adding extra layers or silicone reinforcement. Take a look at some of the most common roof sizes and how much you can expect to pay to install spray foam roofing on each.

Spray Foam Roofing Price by Foam Density

The density of the foam you choose is the biggest cost factor for this type of project. Whether you need low-, medium-, or high-density foam depends on the weather and average temperatures in your area. The more extreme the weather, the more insulation, or the higher the R-value you need. In very hot or cold environments, and those with heavy rainfall, you need higher density foam to provide a higher R-value to reduce heating and cooling costs. 

The prices below are based on a single standard layer of foam.

Low-Density Polyurethane Spray Foam

Low-density polyurethane spray foam costs around $0.47 per square foot, plus labor. The lowest density rating of around 0.4 pounds per cubic foot may cost as little as $0.30 per square foot, while the upper-density rating of 1.4 pounds per cubic foot can cost up to $0.65. Low-density foam is the most affordable option, but it has the lowest average R-value at just 3.6 per inch, providing the least foam insulation per inch. 

The low R-value makes this type of foam comparatively inefficient in hot and cold climates. However, it's a solid, affordable option for homes in more moderate climates, where high-density foam insulation isn't necessary.

Medium-Density Polyurethane Spray Foam

Medium-density spray foam typically costs $1.05 per square foot, for materials only. The lower R-value in foam of this type is 5.5 per inch and can cost as little as $0.90 per square foot. At the upper end, the R-value reaches 6.6 per inch and costs up to $1.20 per square foot. 

The most popular type of spray foam, medium-density polyurethane, is a good compromise between budget and efficiency and is an effective insulator in all but the harshest climates.

High-Density Polyurethane Spray Foam

High-density spray foam costs around $1.25 per square foot and has the highest R-value of greater than 6.6 per inch. At the lower end, expect to pay around $1 per square foot and, at the upper end, $1.50 per square foot, without labor. 

For use in climates with extreme temperatures and heavy rainfall or snowfall, high-density foam is the most expensive but also the most efficient and can significantly reduce a home's carbon footprint and utility costs. It's also much better at withstanding the heaviest rains and resists water damage for longer than the other options. 

Price of Spray Foam Roofing Installation by Cell Type

Spray foam roofing, also known as SPF roofing, is available in open- and closed-cell types. Open-cell foam is the least expensive but also the least water-resistant. Closed-cell foam costs more but is more efficient and waterproof.

Open Cell Foam

Open-cell foam costs an average of $0.47 per board foot for materials only. Open-cell foam types have a lower R-value of 3.7 to 4 per inch—so they’re not efficient insulators. Another important factor is that open-cell foams are not waterproof. So, if you want this type of foam, you'll also need to install a vapor barrier, which can cost up to $0.50 per square foot. 

Because it's comparatively soft and flexible, open-cell foam is a good choice for tight spaces due to its superior expansion capabilities. It's a good, lightweight choice in temperate climates where insulation isn't a big concern. Plus, it has good noise-reducing properties. 

Closed Cell Foam

On average, closed-cell foam roofing costs $1.20 per square foot, without labor. The R-value of this foam typically ranges from 4.9 to 7.1, making it a highly effective insulator. 

The high density of the foam makes it impervious to water and airflow. This makes it a good choice in areas with heavy rain and snowfall, as water can't penetrate, reducing the likelihood of mold problems. Plus, it doesn't need a separate vapor barrier and has a longer lifespan than open-cell foam. Typically, an open-cell roof may only last for 10 years, while a closed-cell foam roof can last up to 50 years.

Foam Roof Replacement Cost

If you decide to apply a foam roof over an existing roof, known as roofing-over, expect to pay between $2 and $3 per square foot. However, if your contractor feels a full replacement is in order, you'll pay more. Replacing a roof costs around $4.50 per square foot, as there's extra labor involved. 

In some cases, where the damage to the existing roof is extensive, or there are underlying problems such as significant rot and mold issues, there's no choice but to replace the roof. 

Regular roof inspections cost around $220, but they help you identify small problems that cost little to correct before they become bigger issues that require full roof replacement or extensive, costly remedial work. Paying for annual roof inspections is a smart investment for your property.

Cost of Foam Roof Coating

Foam roof coatings cost between $0.15 and $3.50 per square foot. 

Acrylic coatings are the most affordable, ranging from $0.15 to $0.75 per square foot. Durable and easy to apply, acrylic roof coatings are spray coats with elasticity and flexibility once dry. However, they aren't as durable or effective as silicone coatings. 

Silicone roof coats cost $1.40 to $2.50 per square foot, plus an additional $0.14 to $0.38 per square foot for each extra layer. Silicone is more costly than acrylic, but it's a more effective waterproofer, too. Plus, it reflects sunlight and has strong resistance to damage from UV light. 

Factors That Influence the Cost of Spray Foam Roofing

Once roof installation wraps up, several other factors will still impact the price, including ongoing costs. 

Aside from regular roofing inspections, it's a good idea to have your roof and gutters cleaned regularly. Roof cleaning costs an average of $430 while gutter cleaning typically costs $160. You may be able to save money by combining these two services. 

Regular cleaning maximizes the lifespan of your roof, removing any debris or substances, such as bird and animal droppings, that can damage the roof's coating over time. 

You can purchase a foam roof repair kit for between $250 and $750 to tackle minor cracks, tears, and patching if you have the skills and confidence to work at height. This DIY approach could save you the cost of hiring a roofer for every little issue. However, we recommend hiring a professional roofer for this job. 

FAQs About Spray Foam Roofing

How long does a foam roof last?

A foam roof will likely last for at least 20 years after installation; it can last up to 50 years if properly maintained. Warranties for closed-cell roofing are usually 20 years. 

Can you put solar panels on a foam roof?

Yes, a foam roof is a great option for solar panels. It's incredibly lightweight and, because a foam roof is normally white, it helps the panels reflect more of the sun's energy.

Can you walk on a foam roof?

Yes, you can walk on a foam roof as its compression strength is 50 to 60 pounds per square inch. However, the surface is slippery when wet. Plus, when working at height, it's important that you take the right safety precautions.