SPF (Spray Polyurethane Foam) Roofing Systems

SPF (Spray Polyurethane Foam) roofing starts out with the use of two liquid components: an isocyanate “A” component and a “B” component of plyol or resin. These two components react with each other when mixed together at a one-to-one ratio, expanding to form a seamless (monolithic), solid fully-adhered and closed-cell, roof system 20 to 30 times its original size and with water-resistant and thermal insulating qualities.

Because it can adhere to virtually any substance, SPF can be used on steel, wood, concrete and most existing roof systems. This helps cut down cost on roof removal as well as landfill fees. Another advantage of SPF mechanics it that can spray apply a tapered roof system with foam that makes it unnecessary to use expensive tapered insulation systems. The vertical wall terminations and cants can also be spray applied that can be integrated into the roof system thus cutting cost on additional components.



The two components of SPF (“A” and “B”) are pumped out of separate 55 gallon drums, combined together at the spray gun, and applied through techniques known as “passes”. A pass uses a single application of foam that varies in thickness: usually half an inch to around a full inch. SPF roofs usually are many inches thick since they entail multiple passes of SPF.

A protective elastomeric coating needs to be installed over SPF. The type of coating should be able to stretch with the foam and bring it back to its original shape. Spray and coatings of different urethranes, butyl rubber, silicone and acrylic can be applied. They each have different costs and have different physical characteristics as well. There are usually three stages involved in coatings: base coat, mid-coat, and final coat. During the mid coat stage, granules can be embedded or to boost resistance of the system to fire, protect against mechanical damage or protection against UV, only the top coat can be applied.

Foam roofs are very tough and are able to handle construction and foot traffic and even other roofs.

The SPF used by Lapolla’s spray foam insulation and roofing systems is called Foam-LOK. Foam-LOK preserves in energy due to its use of an exceptionally high R-value insulation system on the rood deck of the building envelope. This sophisticated roofing system and insulation can be spray applied to any susbtrate and shape specification. It stops heat transfer through the roof deck, prevents the escape of air conditioning and stops outside air from coming into the building.