Sprayed Polyurethane Foam is applied as a liquid using plural-component spray equipment. It then expands approximately 30 times its original liquid volume to form a hard, closed cell monolithic roof surface. The “A” and “B” components (isocyanate and polyol resin) are pumped from separate tanks or drums, into a specially designed proportioning machine. The materials are heated to a specific process temperature and proportioned to the correct ratio. The two liquid materials are kept separate until they pass through the machine, through the heated hoses and out to gun, where they are finally mixed and sprayed onto the substrate. The SPF is applied to a specific thickness defined by the specification. SPF is typically applied in ½ inch to 1-inch layers, or “passes.” Roof specifications or sloping designs that require more foam are applied in multiple passes. The SPF is sprayed down as a liquid, quickly rises in seconds, and can be walked on in minutes. The Polyurethane Foam dries within seconds after applied to the roof surface. Its expansion results in a weather tight roofing membrane that is fully adhered to the substrate. Because of polyurethane’s lightweight it adds little additional weight to the structure and is often used in remedial applications. Polyurethane Foam has a history of more than 35 years as a maintainable roofing medium. Polyurethane Foam adds excellent insulation value to the structure and utility bills can reflect the difference.

Once the SPF has been applied, a protective layer of elastomeric coating and/or gravel is applied. This protective layer produces a durable weather resistant surface and that can be walked on for normal maintenance. In cases of higher trafficability and durability, it may be recommended to use a Cementitious Topped Coated Foam Roofing System.

SPF adheres to just about everything so it can be installed over concrete, wood, steel, and most existing roof systems which saves on the expense of roof removal and landfill fees. SPF Roofing installers can spray apply a tapered roof system with the foam which eliminates the need for costly tapered insulation systems. The cants and vertical wall terminations are also spray applied making them an integral part of the roof system and minimizing additional component costs.

Spraying foam requires at great deal of training and experience to assure proper mixing of the foam is being achieved while maintaining a high level of productivity and quality of workmanship. Spraying foam is an art, and the more experience a contractor has, the better your roof system will look, flow, perform, and drain properly.

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Spray Foam (SPF) Roofing Systems provide many benefits to building owners. Spray Foam is a remarkably versatile energy efficient material that is used to provide many solutions for the building and construction industry. The two most prominent benefits are waterproofing/leak prevention and insulation value. Many additional benefits also exist such as superior comprehensive strength, lightweight, self-flashing, energy savings, durability and long lasting systems with low maintenance. Compared to other insulated roofing systems, a foam roofing system will appear to be more expensive at first. However, over the long-run it is significantly less expensive. Due to the lack of proper public education, there are many misgivings about polyurethane foam. Most people still refer to it as “Styrofoam stuff” or worse yet, they believe it to be hazardous material (both are not true).

LIST OF BENEFITS EXCLUSIVE TO FOAM ROOFING SYSTEMS:

“Green” Roof System
ENERGY STAR qualified
LEED Rated System
Leak free monolithic seal over your entire roof deck
Self flashing
High insulation value / Rapid payback with energy savings
Strong adhesion and high wind uplift resistance
Waterproofing / Weather resistant
Lightweight and high strength
UL and FM approved systems
Superior Compressive Strength
Durable and Long Lasting
Easy Elimination of Ponding Water
Flashing Leaks are non-existent
Minimizes Thermal Shock
Very Versatile

DENSITY AND HIGHEST “R” VALUE
Higher density means increased strength and higher R-value. Most SPF roofs have densities ranging from about 2.5 pounds per cubic foot to 3 pounds per cubic foot. Three pound density foam has a compressive strength of about 50 psi and an R-value of 7.14 installed and 6.86 aged (these numbers may vary slightly depending on the foam manufacturer). A school district in southern California had recently installed some new, one-room relocatable classroom buildings. During the late spring and early fall, these classrooms were using their air conditioners an average of 50 minutes every hour. The school district installed foam roofs on some of these classrooms in order to see if it would provide an energy savings. The roofs consisted of three pound density foam, 1.5 inches thick with an acrylic coating system. The air conditioner usage was cut down to fifteen minutes every hour. That’s a fifty-eight percent savings on energy costs. SEAMLESS Seams are one of the major sources of leaks in roof systems and sprayed polyurethane foam forms a seamless insulated roofing system. It has no joints or seams that often allow outside water and air to pass through the roofing system into the building structure. Whether a roof is 10,000 square feet, 100,000 square feet or larger in size, it will have no seams.

ELIMINATES FLASHING LEAKS
BUR and Single-Ply roofs require flashing material with sealants which frequently result in leaks. Sprayed polyurethane foam solves that problem. Because sprayed polyurethane foam conforms to the substrate and is a seamless monolithic application, it is ideal for flashing parapet walls, roof penetrations and roof mounted equipment, including vents, pipes, stacks, HVAC equipment, skylights, and cooling towers.

LIGHTWEIGHT
One inch of polyurethane foam insulation plus 30 mils of an elastomeric coating weigh approximately 60 lbs per 100 SF, as compared to approximately 600 lbs per 100 SF for a typical conventional four-ply built-up roofing system. CHEMICALLY STABLE It is odorless, resists attack by either mildew or fungi, and has no nutritive value.
MINIMIZES THERMAL SHOCK Because it is seamless, has a high “R” value, and is covered by a reflective elastomeric coating, it greatly reduces the thermal shock a building is subjected to because of fluctuating outdoor temperatures.

DURABILITY AND RIGIDITY
When most people hear of a “foam” roof, they automatically think of the type of soft foam similar to that used for seat cushions and are concerned that they won’t be able to walk on it without causing problems or damaging the roof. Although foam roofs are very light weight, they are very durable and can handle foot and construction traffic as well as other roofs if not better.

FLEXIBILITY
It has the ability to withstand a structures normal expansion and contraction without affecting the ability to keep the structure protected from the outside elements.

WATERTIGHT
Water does not travel laterally in SPF roofs as it can in BUR or single-ply roofs. A leak in the top membrane of a BUR or single-ply roof will create the spreading of water, saturating the insulation and causing multiple interior leaks. Polyurethane foam is made of billions of minute closed cells which resist the penetration of water and vapors. With SPF, even if a hole is punched through the entire thick membrane, water movement will be restricted to the hole.

LONG LASTING
Insulated built-up roof systems, need to be entirely replaced every 10-15 years. That means, the old system may need to be ripped off and an entirely new system purchased. Comparatively, a foam roofing system if properly applied and maintained lasts indefinitely; and will only need to be recoated every 10-15 years depending on the amount of coating installed. Therefore, a foam roof system is significantly cheaper over the long-term. The only element that damages a foam roof system is UV degradation. A typical install on a coated foam roof system will have 30-35 mils of coating. The rule of thumb, is 1 to 1.5 mils is lost every year. Once the amount of mils left is between 17 and 20, UV will be able to penetrate through the coating and will damage the foam.

SKILLED CRAFTSMEN
This is the most crucial element for installation of ANY SYSTEM currently on the market today. Check references, ask to see an existing jobsite, ask to talk directly with one or more of their customers who currently use the same system. Applying a foam system is an art, it requires experience, “Jack with a Foam Truck” just won’t do.

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