Protective Roof Coatings Over SPF

To protect SPF from moisture, foot traffic, and ultraviolet rays from the sun, protection is required. Damage is prevented from any of these elements with a protective coating that seals the foam.

Gravel or a layer of elastomeric coating is applied to protect the SPF once it has been applied to the proper thickness and finish specifications. Producing a weather-resistant surface, the protective layer also makes the surface easier to walk on to provide normal maintenance without causing any damage.

White or light-colored roof coatings are the most common type of cool coatings that are applied over spray polyurethane foam and other deck surfaces. These types of cool coatings can be polyurea, acrylic, silicone, or urethanes.

A thin layer of gravel spread applied over the foam is another protective method used by a few contractors and suppliers. Even though elastomeric coatings are more common, the gravel system has a high success rate. Coatings such as polyurea, acrylic, urethanes, butyl rubber, and silicone are spray-applied as either single or double component systems. It is important to check with an SPF supplier before choosing what type of coating material to use for they all vary in cost due to their different physical properties.

A base coat followed by a topcoat is the typical way these coatings are installed. Granules that offer added protection against mechanical ultraviolet damage are often embedded into the final coat.

To keep your SPF roof system in peak performance for decades to come, coatings require replacement or maintenance. They can be removed or re-applied just like paint on the walls of your house.

During different climate conditions, an SPF roof will expand and contract, like most other systems. Because the SPF expands and contracts, the protective coating should have the same ability of expanding and contracting and it is of the utmost importance that the coating does this, otherwise cracks and damage can occur. The characteristic that matches the SPF and coating system to the climate and roof system is called elongation. For advice on how to properly choose a coating that elongates with SPF and details of said coating, contact your materials supplier. Profoam carries a full line of elastomeric roof coatings for use over Spray Foam or direct to Metal, BUR, and other conventional roofing systems.

Cool Roofing – ENERGY STAR (DOE)

Save money while protecting the environment – that is what a cool roof accomplishes. Utilizing the right coating product can beget heat reflectivity and energy efficiencyIn a similar sense to wearing light-colored clothing on a hot day, roof coatings can provide solar-reflective surfaces to maintain lower roof temperatures.

During the warmer summer months, temperatures can reach 170° degrees F on traditional dark roofs such as a low-slope black asphalt roof, and they can drop to -20° degrees F during the winter in northern and higher elevated regions. Much of the heat generated by absorbing the sun’s ultraviolet (UV) radiation transfers to the building interior, and can have significant adverse effects on energy consumption.

Qualified roof coating material mitigates the amount of air conditioning needed in buildings and can reduce energy bills by up to 50 percent. The Cool Roof Program defines certain standards for solar reflectance, three-year aged maintenance of reflectivity, and emission in roof coating systems. Reflectivity is the percentage of the sun’s heat a roof keeps off a building, and emissivity is the percentage of heat a roof lets out of a building.

Lighter colored (white) roof coatings reflect the sun’s UV rays and heat and can lower the temperature of the roof by up to 100° degrees F.

The most common cool roof coatings used over sprayed polyurethane foam (SPF) and other roof deck surfaces are light/white-colored. The most common types are:

  •  Acrylic – Acrylic coatings are typically water-based. They are a common staple in the market because they are cost-effective, environmentally friendly, and easy to use. They are typically high in reflectivity, which cools the roof down. Acrylic coatings can be elastomeric, allowing for fluctuations in temperature without affecting the actual coating. In general, acrylic coatings help reduce cooling costs at a more economical value, while at the same time increasing the service life of a roof surface by protecting it from UV exposure.
  •  Silicone – Silicone coatings are also very common, and because of their permeability, they tend to be applied on spray polyurethane foam (SPF) roofs.  Silicones are also very well suited for areas with extreme temperature ranges and where UV exposure is more frequent. Once the base coat is applied, a slick surface is generated, and only another layer of silicone coating can be applied as the recoat.