Roof Coating Case Study -
Polyuretahne Foam Roof

This polyurethane foam roof was over ten years old. On average, most of these roof types have 1 to 2 inches of foam sprayed onto an existing roof substrate such as a built up, modified bitumen, or metal roof. They are then coated with either an acrylic or silicone roof coating. Polyurethane foam is a great roof system, but it must be re-coated every ten years to protect it from the sun's harmful UV rays.

The American WeatherStar roof coating system used requires cleaning the top surface of the roof with 1,500 to 2,000 psi of pressure. In order to not damage the current coating system installed on the roof, heavy power-washing is not recommended. We do recommend a detergent, such as TSP, to clean any heavy residue off the roof surface.

The next step was to cut out any damaged foam and spray additional AWS foam into the damaged areas to match the current foam system. It is especially important to cut out any areas where water has saturated the system. If there are only small blisters, these may be cut out and patched using a polyester fabric and one of several top coats to seal the area.

After all areas of concern are addressed, WeatherStar Fabric Bond was applied to the entire roof area to ensure that the top coating will adhere to the current foam roof system. A bonding primer is not always necessary, but there were adhesion concerns on this roof. AWS Bonding Primer 905 and AWS SBS Primer 950 are also suitable adhesion primers.

Finally, two coats of Miami-Dade County approved WeatherStar Silicone 410 are sprayed on the roof surface to form a seamless, bright white membrane to protect the foam from UV rays for many years to come.

Other options on a flat roof include AWS Urethane 520 or if the roof has enough slope and drains water, any one of the American WeatherStar acrylic coatings will work as well.

Note: If your previous foam and coatings project used silicone as the top coat, WeatherStar Silicone 410 should be used to restore your roof as nothing will stick to silicone except for silicone.

Please contact us to receive a FREE survey of your roof!

Choose another roof type below to see the dramatic difference
we can make on your roof: