What Is A Foam Roof System?

Posted on: 26 August 2015

In a traditional home, builders focus on insulating the roof from the inside of the home using fiberglass batts tucked between roof joists. A foam roofing system is a form of energy efficient roofing where the foam itself acts as both roof structure and insulation. While less common than traditional roofs, these sprayed-on systems can reduce energy costs while making the home more comfortable for occupants. Read on to learn how these systems work and whether one might be right for your home.


A foam roof system is a "one stop shop" of sorts; instead of installing multiple layers of substrate and insulation, the foam itself acts as both roof and insulation. Typically these systems are installed over existing roofs but can also be sprayed onto a simple substrate like plywood. The foam consists of a two-part mixture that starts as a liquid and hardens as it dries. Finally, installers apply a top coat, which could consist of a liquid-based elastomeric coating or of some form of membrane like rubber.


Foam roof systems offer energy savings of about 30 percent compared to more traditional roof systems. In addition to these energy savings, these sprayed roofs are seamless, which means fewer leaks, and flexible enough for use around roofs with a large number of penetrations, roof curbs or other obstructions. They are also very lightweight, weighing only about 50 pounds per square compared to the 800 pounds per square of a traditional built-up roof (BUR). 


Perhaps more than any other roof material, installation timing matters a great deal when working with a foam roofing system. Roofs installed when it's too hot, cold, humid, windy or wet will not last, and are subject to blistering, poor adherence and other failures. When having a foam roof installed, you must heed the advice of your installer regarding timing, even if it means waiting a few months. You should never attempt to install one of these roofs yourself, as failing to achieve the proper mixture when mixing the liquid foam will lead to failure or poor results.


When you install a foam roofing system, pay careful attention to the warranty. While you will likely receive a warranty from the manufacturer, installation and labor are covered by the installer's warranty. This warranty will cover any installation-related problems, such as a faulty foam mixture or poor adherence. While there is no industry standard, the National Roofing Contractors Association recommends that you look for an installer warranty with a range of one to two years.