FAQ: Is Spray Foam Roofing Cheaper Than a Traditional Roof?

Spray foam roofing is an excellent way to help protect and preserve your roof without incurring the full expense of a roof replacement.

That being said, a long list of factors can influence how much it costs to apply an SPF coating to your roof, including the condition of your existing roof, the thickness of the spray polyurethane foam applied, and more.

So, is spray foam roofing cheaper than a traditional roof? Can applying an SPF coating help to reduce your costs as a building owner?

Let’s look at everything you need to know about the various factors that impact the spray foam roofing cost.

What Is Spray Foam Roofing?

Spray foam roofing– also known as spray polyurethane foam roofing or an SPF roofing system– is a common roofing solution for commercial, agricultural, industrial, cold storage, and educational facilities. This type of roofing has been used for about six decades and is installed over substrates (either old or new) to help add durability, waterproofing, strength, and insulation. Ultimately, SPF roofing can help extend the life of a roof.

When spray polyurethane foam roofing is applied, it goes on as a liquid and expands into foam. This ends up creating a solid layer across the entire existing roof system.

Spray foam is most commonly applied to reinvigorate and repair an existing roof by replacing any damaged materials and covering the entire roof with spray polyurethane foam.

One of the great things about this type of roofing system is that it can be used in any type of climate. Beyond that, it can last for more than fifty years when properly installed and maintained.

In order to apply SPF roofing, two highly reactive chemicals are combined on the job site. These are polyol/resin and isocyanate, which are pumped through high-pressure heated hoses from separate containers into a mixing spray gun. 

If you’re interested in extending the life of your commercial roof and reducing repair costs, several different commercial roof coatings are available. Be sure to check out our guide to help you pick the best roof coating for your building.

How Much Does Spray Foam Roofing Cost?

Many factors can influence the cost of a commercial or industrial roof, including everything from the location and materials to the environment and state of the existing roof.

It’s generally a good idea to get a few different quotes from reputable roofing contractors before moving forward with a project. You’ll find that there can be quite a bit of variation between quotes and recommendations for the best roofing system for your building.

It will typically cost between $6.00 and $12.00 per square foot for an average 20,000-square-foot commercial roof, including the cost of both labor and materials.

That being said, the cost of a spray foam roof can vary depending on the size of your roof, the thickness of the spray foam application, the condition of the existing roof, the silicone coating cost, and how easy it is to access the roof.

How the Size of Your Roof Impacts the Cost Per Square Foot

The price of a spray foam roofing system can get cheaper per square foot if your commercial or industrial building is larger than 20,000 square feet. The size of your roof can also impact the price of the job.

You can also consider the cost of transporting the materials to the job site, the cost of removing debris, and the logistics of moving equipment up onto your roof and across a large roof.

How the Thickness of Spray Foam Impacts the Cost

On a standard SPF roofing system, the spray foam is applied in a layer of 1.5 inches. The application of this thickness of spray foam alone generally costs between $1.65 and $2.25 per square foot for both the materials and the labor. However, there are a number of reasons that a building owner might want to have a thicker layer of SPF applied, such as increased energy efficiency.

There is a direct correlation between the r-value of the roof and how thick the layer of spray foam is. R-value is a metric that measures how resistant a material is to the flow of heat. Essentially, the higher the r-value of a material, the more insulative it is.

You might choose to run the math on the additional costs you will incur by increasing the thickness of your SPF application versus how much money you will save on your energy bills with a more insulative roof.

How the Existing Roof’s Condition Can Impact the Cost

Another very important consideration when trying to estimate how much an SPF roofing system will cost is the current state of your existing roof. A roofing crew can either strip and remove the roof, fasten recovery boards on top of the current roof, or clean and prepare the existing roof.

The most expensive of these options is to strip and remove the old roof, which typically costs between $1.00 and $2.00 per square foot. You might need to do this if your roof is damaged, unstable, saturated, or if two roofs are already installed on the building. In the first case, a new roof will need to be installed. In the second, one of the two roofs will need to be removed in order to install the SPF.

The second most expensive option is to have recovery boards fastened over the roof that is currently on your building. This costs, on average, $0.60 to $0.80 per square foot. Fastening recovery boards on top of the current roof can help provide a layer of separation between the old roof and the new roofing system, as well as cover joists. This is a common way to create a better application surface before applying SPF.

Finally, the least expensive option is for the roofing contractors to simply clean and prepare the roof that is currently on the structure without making any significant alterations. This usually costs between $0.10 and $0.75 per square foot. If your existing roof is solid, roofing professionals can clean and prepare the roof through air pressure cleaning, dry vac, wet vac, power washing, or some combination of these cleaning methods. Properly preparing the roof is essential in order to ensure that the foam will adhere to the surface properly.

How Silicone Coating Impacts the Cost of an SPF Roofing System

A layer of silicone with embedded granules will need to be used to seal the SPF layer. This is an important part of the process as it helps to protect both the foam and the roof from impact, weather, and UV light. For both labor and materials, the average cost of applying a silicone coating is between $1.75 and $2.30 per square foot.

Before your SPF roofing system installation is complete, at least two coats of silicone coating will need to be applied. If you choose a longer warranty, you’ll need to apply a thicker layer of silicone than you will with a shorter warranty.

How Does Roof Access Impact the Cost?

The cost of installing an SPF roof is also going to be impacted by how easy it is to access the roof. If your commercial building has a roof that isn’t flat or can’t be walked on, it is likely going to increase the cost of the project.

For example, a sloped roof will typically require that professional roofers use rappelling gear or a man lift in order to install an SPF system. Beyond that, moving both the crew and the equipment might mean that the roofing company needs to rent conveyance equipment.

Finally, the cost of installing commercial SPF roofs can also be increased if the building is in a secure location. This is because contractors might need to maintain SIDA authorization (Secure Identification Display Area authorization) on job sites like airports, which means that the contractors will be incurring additional costs.

Is Spray Foam Roofing Cheaper Than a Traditional Roof?

Unfortunately, there is no one-size-fits-all answer to whether spray foam roofing is cheaper than a traditional roof. This is because there is a wide range of options when it comes to the type of roof you install on a commercial or industrial building.

In some cases, an SPF roof application can help preserve and protect your existing roof without incurring the costs of a full roof replacement. If the roof of your building is in pretty good shape but needs additional help dealing with leaks and other problems, an SPF coating can be a great solution to help increase the longevity of your roof.

On the other hand, if your roof is in rough shape and will need extensive repairs or a full replacement before an SPF coating can be applied, the cost will increase. Beyond that, many different factors influence the cost of an SPF application, which we outlined in the previous section.

For more information about other options for commercial roofing systems, make sure you check out our article comparing TPO, EPDM, and PVC.

When determining the cost of a roofing system, you don’t just want to think about how much you will shell out in terms of labor and materials. You also want to consider how much it will cost to maintain and repair the roof, how long the roof will last, and whether the roof will save you money on your energy bills.

SPF roof coatings can help your roof last longer, repair existing small holes and tears, prevent future leaks, and increase the energy efficiency of your building. For these reasons, SPF can help save you money over the long term.

It’s a good idea to have a few different roofing contractors come out to take a look at your building and offer some quotes. This way, you can get specific feedback about the state of your roof, what the SPF application process would look like for your particular circumstance, and roughly how much it would cost.

What Are the Pros of Spray Foam Roofing?

There are a lot of valuable benefits to an SPF roof coating, including:

• ● Costs: SPF roofs can be more cost-effective over the life of the roof in many cases
• ● Installation: Applying SPF is quick and easy, which can save you both time and money
• ● Easy maintenance: Only minimal maintenance is required after installation
• ● Lifespan: A properly installed and maintained SPF roof can last more than fifty years
• ● A watertight layer: SPF coatings eliminate the vulnerability of seams and penetrations as it is seamless and fills existing seams, gaps, and cracks
• ● Energy efficiency: With an extremely high R-value per inch, this is a great way to better insulate your building and keep your cooling costs down
• ● Closed-cell properties: The structure of SPF helps to prevent leaks even if the roof gets punctured or cut thanks to its closed-cell properties
• ● Environmentally friendly: Installing SPF on top of an existing roof means you don’t have to throw away your existing roof, and SPF roofs create little to no waste throughout their lifespan

Is It Time to Preserve and Protect Your Roof?

Making cost-effective decisions is essential for any building owner or manager, and the cost of repairing, replacing, and maintaining a commercial roof can vary greatly depending on your decisions. Spray foam roof coatings can help to reduce repair costs as it creates a seamless barrier over your existing roof and helps to seal up small holes and tears. Beyond that, it can help to ensure that new leaks don’t develop.

If you are looking for a cost-effective and viable alternative to a roof replacement, spray foam roofing might be a good option. Not only can it be more affordable than a full roof replacement, but it will also help extend your roof’s lifespan.

Additionally, you also have to factor in the savings you will enjoy from an SPF roof coating, thanks to the added insulation. This means that your HVAC system will be less strained, and you’ll save money on energy bills.

Are you ready to help preserve your roof and save money at the same time? If so, you’ve come to the right place. At Colony Roofers, we specialize in providing the highest-quality roofing systems at the most affordable prices in the greater Atlanta area.

If you’re exploring your options when it comes to commercial roofing solutions, contact us today to schedule a free estimate.