The future of roofing technology with timeless styling
Silicone Roof Coatings have been a high-quality roofing option for a while, but people are unaware of what it can do for your commercial roof. Silicone roofing is durable to sun damage and bad weather and can withstand standing water without ever losing any of its coating. It’s eco-friendly and available in different colors. Finally, it’s also convenient and easy to use.
With more than 30 years of experience, we are the roofing experts you’ve been looking for in the Fort Smith and Northwest Arkansas area.
Roof Selection Guide
Download this free roofing guide and you’ll get valuable tools and information you’ll need to pick the right roofing product.
Silicone Roof Coatings have many different benefits for your commercial roof, including:
- Coatings are usually applied in one coat due to the coating being applied thick. This is a huge time and labor saver, and ensures you get a high-quality product without paying more in labor than you would other coating options.
- Silicone Coatings are safe for the environment. They are solvent free and contain extremely low VOC levels. They meet and exceed material safety standards in all 50 states.
- The Coatings are not flammable.
- Coatings maintain adhesion and remain leak-free under constant water pressure.
- Easier to install, repair, and replace than any other type of roofing.
Silicone Info and Misconceptions
“Silicone Roof Coatings are Waterproof”
This is the most common misleading and incorrect term associated with silicone roof coatings, “silicones.” The correct terminology is that silicones are water-resistant, or more specifically water-repellent. The term waterproof means inherently being impervious to water; water cannot penetrate the membrane or coating. All silicones on the market today possess some level of permeability, typically 3.0-12.0 perms. This allows water vapors to permeate through the coating due to forces from hydrostatic pressure.
Silicones hold ponded water, which the National Roofing Contractors Association (NRCA) defines as holding pooling water for 48 hours. It is in the very nature of roof coatings to be permeable. This allows trapped moisture in the decking, insulation, or underlayment to evaporate allowing the building to breathe. If silicones find themselves in ponded water circumstances for periods longer than 48 hours, water begins to penetrate the coating. This will make its way to the underlying membrane or coating. After this, there is adhesive failure, coating delamination, telegraphing, and blistering. Roofing systems are waterproof due to the type of membranes or barriers that are underneath the silicone coating. However, even the best of the silicones by themselves are not waterproof.
“Nothing Sticks to Silicone”
This is a myth that has been perpetuated for years. It is true that asphaltic and bitumous mastics, cements, coatings, and emulsions as well as water or solvent borne acrylics, polyurethanes, and even Sprayed-in-place Polyurethane Foams (SPF) do not have positive adhesion to silicone coatings so it is understandable where the myth came from.
To put some brief science and explanation behind the phenomenon, silicone films have lower surface energies than most. Especially compared to other coating types in the market place, coming in around 20-30 dynes/cm. For reference, Teflon™ and non-stick coatings are around 18 dynes/cm. In contrast, acrylic and epoxy coatings tend to be closer to 40-50 dynes/cm. The lower the substrate surface energy, the more difficult it is to adhere to the substrate. Silicones have low surface energy so they are difficult to adhere to. This means cured that silicone surfaces are slick and slippery.
The answer is knowing which silicone coatings in the market place have low surface energies. Then choose one that can stick to other higher surface energy silicones and coatings. It is important to be aware that certain silicone technologies in the market do adhere to existing and new silicone coatings.
“Silicone Roof Coatings out-compete Acrylic Roof Coatings”
More than just an opinion, this idea has proliferated the roof coatings industry for nearly a decade. As one may guess, opinions aside, there are pros and cons that exist for both silicone and acrylic roof coatings. Silicone coatings show greater resistance to ponded water areas than do acrylic coatings while acrylic coatings have greater Dirt Pickup Resistance (DPR) and much greater tear resistance than their silicone counterparts. There are times and places suited for both technologies. Below is an analysis of when to use either coating.
Generally, positively sloped roofs with inclines greater than 1/12 are excellent candidates for acrylic top coats. Roofs with a positive slope and good drainage all throughout will not need a silicone coating for the entire space. In addition, the dirt pickup resistance and hard film of acrylic coatings are a great plus. The coating is more durable and less likely to take damage from hail, foot-traffic, and/or debris from storms and winds. In those low-lying areas where ponding may occur, silicone coatings will apply in a hybrid type manner as a patch over those areas but the remainder of the roof can be coated with the acrylic coating. This will allow the roof coating system to be “tailor-made” and custom to that specific roof, utilizing the strengths of both the acrylic and silicone coating together.
Near dead-flat and low-sloped roofs with inclines less than 1/24 (½:12) should immediately call into mind the need for a more water-resistant solution than an acrylic top coat. Areas with very low slope, less than 1/24, are highly susceptible to ponding and a silicone coating make sense. With ponding, the acrylic coating will swell which leads to potential leaks in the roofing and coating delamination. If the low-sloped roof exhibits no signs of ponded water and there is adequate, positive drainage then either coating type is likely a candidate to consider.
There are downsides and upsides of both coatings to consider from a cost, labor, and application standpoint. For instance, silicone coatings have better resistance to water ponding. In contrast, acrylic coatings have more tear resistance, greater DPR performance, and greater durability.