What Is Silicone Roof Coating?

Silicone can be used as a liquid applied roof coating to provide waterproof characteristics and UV stability. Roof substrates of all kinds break down over time and eventually cause roof leaks. These leaks typically cause expensive damage to the building itself, as well as the contents of the building.

As roof substrates age they eventually begin to fail. When this happens, a building owner has three obvious options:

• Repair the leaks. Repairing leaks can be very challenging. The source of the leak is often very difficult to find and the repair is simply a band-aid approach that offers a short-term solution.
• Roof replacement. Not only are roof replacements very costly, but the material from the original roof ends up in a landfill. Many building owners are looking for more ecofriendly solutions to the maintenance of their buildings.
• Maintenance coating. Using silicone as a maintenance coating is a way to offer a long-term solution while being much more cost efficient, and ecofriendly, than a full roof replacement. When done properly, a silicone roof coating offers a new layer of protection that can last for years.

Why does silicone work as a roof coating?

The benefit of silicone as a roof coating comes from its non-carbon nature. Silicone is inherently resistant to bacteria growth and resists degradation from ponding water while still providing breathability for the substrate. This breathability helps to protect the substrate which leads to a longer lifespan.

When is it best to use silicone?

Silicone is used when there are concerns associated with UV stability. Silicone is naturally resistant to ultraviolet rays which cause oxidation and can reduce the life of a roofing substrate. Another benefit of silicone is its ability to withstand indefinite exposure to ponding water. Proper drainage is always necessary on a low slope roof, but the risk of standing water still exists. A silicone roof coating provides a waterproof barrier that protects the roofing structure, which in turn helps to expand the lifespan. And since silicone is resistant to mold and mildew, dirt and grime build-ups can easily be washed off with water.

What are the best silicone products and why?

There are three main types of silicone for the liquid applied roofing industry:

• High Solids Silicone is the most used silicone roof coating. With the ability to apply by spray, roller, or brush, it offers lower VOC, a glossy finish, and decreased application time due to higher volume solids.
• Standard Solids Silicone has a higher VOC content, but gives better adhesion and a smoother finish with less roller marks and brush strokes. A lower solid content does mean a lower volume solid, but with the increased adhesion this is the preferred product for recoating other silicone.
• Silicone Flashing Grade is an extremely thick silicone that is used for flashing or seams when combined with fabric. A high solids content in the mastic allows for minimal shrinkage while maintaining excellent adhesion and flexibility. Adhesion and flexibility are important because they allow the flashing grade to move without cracking and remain fixed to the surface.

How is silicone applied?

Silicone is extremely easy to apply. The first installation method is by brush. This is normally for silicone flashing grade or for application over seams in combination with fabric. The second method is roller applied. Roof silicone is compatible with almost all roof roller types. The third method is spray applied and is usually done with a high-pressure spray rig.

Silicone plays a large role in liquid applied roofing. The advantages as a maintenance coating far outweigh costly roof replacements. The properties of silicone are superior to other fluid applied products like acrylic. And more roofing contractors are realizing the benefit of offering application services to commercial building owners. The choice is simple. Contact us today for a free roof inspection from a VFI authorized roofing contractor in your area.