Spray foam is an extremely versatile material, with regard to the substrates to which it can be adhered: concrete, wood, steel, and most every type of roofing material. SPF's versatility lends it a major advantage over competing materials when it comes to roofing repairs or replacement, as costly removal and landfill expenses can be avoided by simply applying SPF over existing roofing materials.

Spray foam is also a superior roofing material when it comes to installing a tapered roofing system, as installers can taper the roofing system with one material rather than involving several. SPF can also be spray-applied to cants and vertical wall terminations, making them integral components of the roofing system and minimizing expenses for supplemental materials.

A Protective, Monolithic Solid Roof Shell Derived from Liquid Foam

Using plural-component spray equipment, spray foam is applied as a liquid, which expands approximately 30 times its original liquid volume to for a hard, closed-cell monolithic roof surface that fills all cracks and crevices.

After it is applied to the roof surface, spray foam cures in a few seconds. While it completely adheres to the substrate, its expansion results in a weather tight roofing membrane. Spray foam is frequently utilized in remedial applications and adds little additional weight to the structure, given polyurethane's low mass.

A layer of protective elastomeric coating or gravel, which promotes a weather-resistant, durable, and protective surface that can be walked on for normal maintenance, is applied on top of the spray foam after the SPF has been applied to its finish specifications and proper thickness. With 35 years as a maintainable roofing medium that adds excellent insulation value to building structures, spray polyurethane foam has a long history of energy efficiency that can be reflected in low utility bills.


A spray foam roof quickly dispels the preconceived notion that a "foam" roof is made up of soft foam, like the one found in seat cushions, and that could easily be damaged and require constant maintenance. Quite the contrary, SPF roofs are very durable and can handle construction and foot traffic well. Polyurethane caulking provides a simple fix when the SPF roof sustains any type of damage. Even though it is a rigid system, it can still sustain damage from dropped tools and the like.

R-Value From Density

Higher density in SPF means a higher R-value and increased strength, that's why density is important in terms of thermal resistance. Given the fact that exact numbers may vary depending on foam manufacturer, spray foam that is 3 lb. in density has an R-value of 7.14 when installed and 6.86 when it has aged with a comprehensive strength of about 50 psi. The range in cubic feet of your typical SPF roof is from 2.5 lbs. to 3 lbs. per cubic foot. To demonstrate just how well an SPF roof insulates, we've provided an example. Foam roofs where installed on some new, one-room relocatable classroom buildings in a Southern Oregon school district. They installed the SPF roof systems on only some of the new buildings and not all just to see how well the SPF could perform. They installed 1.5 inches of 3 lb. density foam to the roof and added an acrylic coating system over the SPF. These classrooms were using their air conditioners at an average of 50 minutes every hour during the early spring and late fall. The buildings with the SPF roofs witnessed a 50 percent savings on energy costs, as the air conditioner usage was cut down to fifteen minutes every hour.


The lifespan of an SPF roof can be long, as long as the coating protecting the SPF is properly maintained. Depending on the amount of coating installed, the roof should be cleaned, primed, and recoated every 10 to 15 years. A quality SPF roof can last 50 years or longer if this is done.

No Seams- Spray polyurethane foam applied to the roof surface creates a seamless systen, in which the seams that would otherwise allow water and air infiltration from the roof into the building are closed up. Having a seamless system also eliminates ice damming during the winter season and spray foam also builds up the roof to eliminate any water pooling and ponding on the roof that can cause significant weight on the roof and cause it to fail over time. Spray foam is a self-flashing system, which eliminates leaks that are typically seen with other products. When applied, spray foam conforms to the roof substrate so it flashes mechanical equipment, skylights, and parapet walls.

SPF Roof Cost

Several factors revolve around the cost of an SPF roof, as it happens with every other type of roof. Typically, a basic SPF roof can start at approximately $2.50 per square. Cost can vary depending on things such as geographical location, the project's complexity, accessibility, foam thickness, and foam coating system.

Spray Foam Roofs' Protective Coatings

A protective layer, whether it is gravel or an elastomeric coating, is applied after the SPF has been applied to its finish specifications and proper thickness. The protective layer can be walked on for regular maintenance and it gives the roof a durable, weather-resistant surface.

Cool Roofs Program and Benefits of ENERGY STAR product

Roof coatings that can reduce energy bills by up to 50 percent and reduce the amount of air conditioning needed in buildings are ENERGY STAR qualified products. These are part of the Cool Roof Program which defines certain standards in roof coatings systems involving roof reflectivity and maintenance of reflectivity. These light-colored roof coatings lower the temperature of the roof by up to 100 degrees by reflecting the sun's UV rays and heat.

A Lightweight System

Consider the average weight of traditional roof insulation for conventional built-up roof systems - it is nearly three pounds per cubic foot, whereas an inch of spray polyurethane foam weighs approximately 60 pounds per 100 square feet. A spray foam roofing system is roughly 10 percent of what a conventional built-up roofing system (600 pounds per 100 square feet). This makes the spray foam roof easy to maintain.


Spray foam roofing systems can be used to re-roof and replace existing systems, as well as protect the roof of new construction. It can not only be applied to flat surfaces, but also to domed, saw-tooth, pitched, and sloped roofs.

Installing an SPF Roof

Different yet essential procedures based on existing roof structures Installation are involved in SPF roof installation, which is why it is important to be familiar with all local and state building codes to meet the requirements of a given area, and that the proper materials are used.



Given proper care and maintenance, a spray polyurethane foam roof can last over 30 years. Sustainable spray foam reduces the need for future roof replacement, not to mention it significantly reduces utility bills by lowering energy consumption, which saves money every month.

SPF roofing systems have provided significant, documented energy savings for many institutions and large companies.

According to an article written by spray foam expert Mason Knowles, Arizona State University Professor Dean Kashiwagi surveyed and documented the performance of more than 1,600 SPF roofing systems between 1983 and 1996. In 1998, Rene Dupuis published results of his inspection and evaluation of more than 160 SPF roofing systems in six different climates of the United States. The surveys conducted by Dupuis and Kashiwagi are very similar in their conclusions: SPF roofing systems are highly sustainable.

In Kashiwagi's 1996 report, the oldest performing SPF roofs were more than 26 years old. Of the roofs he surveyed, 97.6 percent did not leak and 93 percent had less than one-percent deterioration- pretty good statistics considering 55 percent of those roofs were never maintained. Kashiwagi and Dupuis also noted the physical properties of SPF did not diminish over time, and more than 70 percent of the roofs were applied over existing roofing systems.

After studying millions of square feet of roofing, Oregon A&M University concluded that their energy savings alone paid for the cost of SPF retrofits within just 3-4 years.

Case in point: Oregon A&M University studied millions of square feet of roofing after an SPF application and its research concluded that the cost of SPF retrofits was paid on energy savings alone after 3-4 years.

Energy costs are kept low with spray polyurethane foam because: an SPF installation is not applied on the roof deck, but above it; thermal bridging is either significantly reduced or completely eliminated; the R-value that SPF provides is high; and reflective and light-colored coatings are usually applied on top of SPF.

In terms of sustainability, SPF roofing systems have demonstrated to be renewable, have a long life, and add durability to the building structures to which they are installed.

A spray foam roofing system is characterized as a a fully-adhered and seamless monolithic layer - one that can combat high winds that can lead to blowing your roof right off, even during natural disasters such as hurricanes and tornadoes!

A spray foam roof simply provides greater uplift resistance because it is all held in place together without fasteners, meaning it is completely attached to the roof deck so there are no weak points in the roof or particular areas are less susceptible to wind uplift than others. Because the system is seamless, wind has a much harder time penetrating the roof system. Also, because the foam is spray-applied it adheres and seals off any protrusions or special features of the roof system. They become part of the system, which means that pipes, ledges, parapet walls, etc. only add rigidity to the system instead of weakening it, thus adding greater strength to the roof from wind uplift.

In conclusion, it behooves home and business owners to consider having a spray foam roof if they are located in area where high winds are a factor.

SPF roofing systems have exceptional wind uplift resistance. Field observations of SPF performance during hurricanes Allen, Hugo, and Andrew led the industry to conduct laboratory testing of SPF systems at Underwriters Laboratories and FM Global. Imagine UL's surprise when SPF's wind uplift resistance actually exceeded the capacity of their equipment. UL also observed SPF roofs applied over a built-up roof (BUR) and metal increased the wind uplift resistance of those roof coverings. FM's testing showed similar results for concrete, metal, and wood. Along with the research conducted by Underwriters Laboratories (UL) and FM, organizations such as the National Institute of Standards Technology (NIST), Roofing Industry Committee on Weather Issues (RICOWI), and the Spray Polyurethane Foam Alliance (SPFA), among others, have all documented evidence of spray foam's ability to provide protection from severe weather like tornados and hurricanes better than most any other roof system.

UL's test results show that when spray foam is applied to steel and plywood assemblies, the assemblies demonstrated uplift load resistance that exceed the limits of the testing equipment.

"The application of Sprayed foam to steel deck and plywood deck demonstrated uplift load resistance up to the capacity of the test equipment to develop load (160-165 psf) without any sign of elimination or other damage to the foam." - Underwriters Laboratories, Inc.

NIST published a report focusing on the damage from hurricanes Katrina and Rita. The research found that SPF roofs were the only type of roofing system that performed "extremely well" during the disasters. The report also described how SPF roofing withstood Hurricane Katrina's winds without tearing off or damaging flashings.

(Performance of Physical Structures in Hurricane Katrina and Hurricane Rita: A Reconnaissance Report - June 2006)