



Using Spray Polyurethane Foam Extends the Life of Your Roof.
50 Year Material Warranty for all restoration projects.
No Day-to-Day Business Interruptions during installation.
Say Goodbye to Leaks; SPF creates a watertight seal.

Extend the life of your roof at a fraction of the cost of a full flat roof replacement.

TPO Roofing, known as an energy star rated eco-friendly flat roofing option.

EPDM Roofing Systems are an economical install without disturbing day to day business.

See an overview of our commercial roofing service options and comparisons.

PVC Roofing is popular for being heat reflective, lightweight, & eco-friendly

Modified Bitumen is the classic standard in flat roofing, but has recently fallen in popularity.

See an overview of our industrial roofing service options and comparisons.
What is Spray Polyurethane Foam (SPF)?
When we talk about Spray Polyurethane Foam (SPF), we wonder what exactly it is used for, how it is used, and what exactly it is. SPF is made when two forms of chemicals are used to create and react quickly by expanding on contact creating a foam that fills seams and creates air tight seals providing a moisture barrier. When Spray Polyurethane Foam is properly installed, it forms a continuous barrier on walls, around corners, and on contoured surfaces. Because of this feature, SPF can resist heat transfer very well, which in return becomes an effective solution for reducing the unwanted air infiltration through cracks, seams, and joints. When applied by professional roof installers, it is usually defined as either high or low pressure foam where it is available as either an open or closed cell. Each type has its advantages and disadvantages depending on the application requirements.
SPF creates a roofing system by mixing and spraying a two-component liquid combination that forms the foundation of a bonding roofing system. One of the components, Isocyanate, is referred to as Component A. Component A will react chemically with Component B, Polyol Resin, immediately when mixed. This mixture will cause an expansion of about 20 to 30 times its original liquid volume in order to form a closed-cell foam. Therefore, the SPF insulation ends up becoming fully adhered to an acceptable underlying substance, exhibiting a degree of water resistance.
How is SPF Used?
SPF systems can be applied in various densities and with each density they will exhibit different physical properties. Therefore, the thickness of the SPF, the number of lifts, the temperature of the substrate, and the current temperatures all affect the in-place physical properties of SPF. The number of lifts would be defined as the number of layers required. Multiple lifts over the same area would most likely be needed in order to achieve the final foam thickness.
Component A, as mentioned before, is one of the mixtures that create SPF. It is composed of a high-molecular-weight polymeric isocyanate. The point of the isocyanate is so that it can react with Component B to form the polyurethane foam. Besides isocyanate being able to be combined with another component, it also reacts rapidly with excessive moisture in any form resulting in the generation of carbon dioxide. Carbon dioxide, however, may cause inferior cell formation and/or poor-quality SPF, therefore, it should be applied on a dry surface.
Component B, on the other hand, is a mixture that contains polyols which is commonly called resin. This mixture contains polyols, an organic compound that contains multiple hydroxyl groups. When polyol reacts with isocyanate, it forms polyurethane foam. A blowing agent is a substance that is capable of producing a cellular structure such as a foaming process. The low temperature blowing agents boil at the polyurethane foam reaction temperatures in order to form the cell structure of SPF.
How is SPF Installed?
With all the information that was given above, there must be some questions on how Spray Polyurethane Foam is installed. Well, the first thing before installing, is that the existing roof or roof deck, otherwise known as the substrate, needs to be prepared. The roofing contractor will prepare the roof by getting rid of all the dirt, dust or any other contaminants. The contractor would do this by simply using air pressure, vacuum, or just by sweeping it off. When reroofing, any wet existing components would need to be removed and replaced before the application of a new roof.
When that is all done, the contractor would then put the polyurethane foam as the first layer on top of the roof deck or existing roof. When the liquid is sprayed on the substrate, it would create a foam that would expand 20 times in size to form a solid, seamless foam surface. When that foam has expanded enough, that layer can be between 1 to 1.5 inches in thickness. The fact that polyurethane foam sticks fast to the most common surface, it can be installed on any type of roof slope. Once the SPF layer is completed, it would then be coated with layers of elastomeric or acrylic coating with embedded granules. The roof coating protects the roof as well as the SPF from UV light, weather conditions, normal wear, and satisfies the required fire ratings. After installation is completed, you are left with a seamless, durable, moisture-resistant, renewable foam roof covering.
Learn more about the Roof Coatings that will be installed over an SPF installation
Advantages of Spray Polyurethane Foam
We may know what SPF is and how SPF is installed, but we don’t know what advantages it comes with. Well, some of the advantages of SPF for a roofing application is its energy efficiency, durability, seamless, waterproof, and is environmentally friendly. With its energy efficiency, SPF distributes thermal, air, and moisture barriers to give the highest R-value per inch, which means the material provides better insulation for the building.
The durability of the foam allows for the material to expand and contract with the building in accordance with outside temperatures, decreasing the likelihood of cracks and splitting. Once installed, the SPF roof can be walked on without causing damage. If for some reason the roofing system is damaged, there are typically no leaks because the puncture usually doesn’t go through the full thickness of the foam.
Having seamless and waterproof features is absolutely essential when it comes to your roof. This is another advantage of SPF because of the fact that the SPF mixture is applied as a liquid, which can fill any gaps, seams, and cracks in the existing roof and substrate. The continuous solid surface does not require joints or seams, removing the most vulnerable area of leaking. SPF roofing can be installed by the technician to level out uneven roofs to reduce ponding water.
Here at Infinite Roofing, we strive to be as environmentally friendly as possible while completing our projects. SPF helps with our goal of being environmentally friendly because SPF does not produce any waste after installation, as long as it is properly maintained, which keeps the SPF roofing systems out of landfills. There are a variety of eco-friendly roofing products, which feature zero ozone depletion potential, ultra-low global warming potential, and solvent-free silicone coatings.
Disadvantages of Spray Polyurethane Foam
Hiring the right professional roofing contractor is one of the most important things when installing your roof. It’s important because when applying the spray polyurethane foam, it needs to be installed correctly from the beginning. The roofing installer needs to be able to be precise with the application and have a solid understanding of the chemicals that are being used in the process. If the roofing system is installed incorrectly, it can be detrimental to the lifespan of your roof. Another disadvantage of installing SPF is the timing. The reason is because the installation of an SPF roofing system cannot be performed during the cold or rainy weather. Meaning that there should be absolutely no SPF roofing systems being applied when the roofs substrate is within the 5 degrees Fahrenheit of the dew point as measured at the job site. The substrate temperature should be ranging from 50 F and 180 F. When the temperatures are below 50 degrees Fahrenheit, then low temperature, factory formulated materials, and high-temperature application techniques should be used. SPF also should not be applied while wind conditions exist that are strong enough to prevent any application when surface textures are acceptable. SPF should not be sprayed when winds exceed 12 mph at roof height unless there is some form of windscreen that is being used. In addition, the substrate needs to be completely dry and pass an infrared moisture survey.
SPF does not have a high resistance to punctures, therefore there is a persistent risk of mechanical damage as well as punctures being caused by branches, debris, or any animals with beaks or claws, which is the same for most roofing systems. The repair process would be very simple with a standard cartridge of caulk, unlike repairing other roofing systems. Even if the system was to experience mechanical damage, the upside is that there would be no leaking because of the thickness of the SPF. The closed-cell nature of the foam prevents any water from traveling laterally throughout the system.
When there is a lack of Isocyanate (Component A), it will exhibit a light color, slow and insufficient rise, a soft and spongy texture, and improper cell structure. The reason this a disadvantage is because this type of SPF would not be acceptable physical properties for installation. This SPF also will be vulnerable to water absorption and should be removed if this type of SPF was installed. A simple test that can be performed would be to cut out a small piece of the applied SPF, submerge it in water, and observe if it has an immediate water absorption. The lack of Polyol, also known as resin and component B, is more difficult to discover unless the condition is extreme. However, SPF that is applied with a slight excess of isocyanate is not as seriously affected as when isocyanate is lacking. That might be confusing, the reason why it’s not as seriously affected is because in this case the polyol is still reactive. What you would need to be looking for to find out if there is a lack of polyol, is when the product has a dark color, smooth, hard surface, irregular glassy cell structure, and improper density. All of these characteristics would tell you that there is an extreme lack of polyol. If any of these were to occur, the SPF should be removed and replaced to prevent any damage.