Spray Polyurethane Foam Roof Installation

Choosing a Foam Coating

• You will need to hire a contractor with foam roofing experience to spray the roof and properly treat it. One of the most important decisions you will be making yourself is what kind of foam you will be using. There is only one type of polyurethane foam that is used to form the base of the roof, but an additional coating is also applied to protect the foam. This coating can be made from a wider range of materials. You may need to choose from acrylic, butyl rubber, hypalon, silicone, and other materials. Choose based on price and durability. You will want a coating that is not too expensive, but also one that will last as long as possible. Silicone options are popular for wet climates, since they have strong waterproofing capabilities. Elastomer options may hold up better in warm weather.

  You should also choose a type of coating based on its appearance. Most contractors will offer several coatings with mineral particles or sand in them. This gives the coating a more natural look and affects the general appearance of your roof. Try to choose a texture and material that blends in with your landscaping and looks natural compared to the other colors of your house.

Process

• The contractor will combine the foam compounds and spray it on site (this is usually done on a flat roof, but can also be done on more common slanted roofs with the right techniques). The foam begins as two liquids that the contractor will bring in tanks to the site, and then pump together before spraying it. It will quickly harden and dry, but the contractor may go over the roof a second time so that the foam reaches the proper height. Find a contractor who is aware of local building codes and how they affect the foam roof.

Additional Coatings

• After the foam is completely dry, the contractor should spray on a base coat over the foam to protect it, then apply the final coating, which seals the foam from weather damage and adds the gravel or texture you chose. With this coating in place, the roof can be walked on for regular maintenance. When finished, the roof should still be light in color so that it reflects sunlight and dissipates heat.