After 70+ years of application, roof coatings are tried and tested. They provide a wide range of benefits for any commercial property owner, whether you’re looking to extend the life of your aging system or protect your new roof.
There are many different factors to consider when choosing the right material for your roof coating, i.e., cost, roof slope, and long-term expectations.
It is important to note that roof coatings are a way to extend the life of a commercial roof; however, it is not a solution that will last forever. In this article, we will discuss the benefits of commercial roof coatings, compare the types of coating materials and applications, and advise on when coatings are no longer a viable solution.
Benefits of Roof Coatings
Commercial roof coatings provide numerous benefits, including cost, durability, and relative ease of application. Many building owners will opt for a roof coating when their existing roof is starting to show signs of deterioration but does not need to be fully replaced. When this occurs, expert roofing contractors can evaluate and determine a viable solution to extend the roof's life. Beyond the waterproofing benefits, a newly applied roof coating is also aesthetically pleasing as it can make an old roof look new again.
Roofs with minimal damage to the existing roof and only experiencing minor water penetration issues are good candidates for coating. The durability of the appropriate material will provide immediate results and mitigate the problems the building is experiencing. This makes coating a roof a much quicker and more affordable solution versus a complete tear-off and replacement.
The sooner these problems are recognized, the more likely a qualified commercial roofing contractor can save your roof. If the underlying roof system is failing, for example, the membrane laps are splitting loose, then coating is not a good solution. A coating system can only perform when the underlying roof system is intact.
It is also important to note that roof coatings are not exclusively for repairing and restoring a roof’s viability. The proactive application of a roof coating during the installation of a new roof can offer additional protection and extend the expected life of the roof. In some cases, the architectural purpose of the roof may require a coating to enable the roof to sustain excessive weight and wear or obtain a reflectivity credit.
Types of Commercial Roof Coatings
There are four basic types of commercial liquid roof coatings. Three could be classified as a traditional coating that extends the life of an existing roof. The fourth type is a more innovative product designed to strengthen a roof to hold pavers or heavy foot traffic.
The traditional roof coatings are acrylic, polyurethane, and silicone. The roof coating designed for heavy reinforcement is called PMMA.
Acrylic Roof Coating
Acrylic roof coatings are water-based, easy to apply, and generally the most cost-effective of all the commercial roof coatings available. These characteristics make this solution a popular option. Another advantage is the material’s high UV resistance, which can drastically reduce a building’s energy costs during the summer heat.
There are also some disadvantages to using an acrylic roof coating. First, the solution is prone to weathering over time and will lose thickness due to extreme environmental conditions. Additionally, the material is very susceptible to ponding water, so it is generally only recommended for flat roofs with exceptional drainage or sloped metal roofs.
Polyurethane Roof Coating
Polyurethane roof coatings are solvent-based and also provide a low-cost option. Additionally, this material offers good abrasion resistance and mechanical properties. These characteristics make this solution a good choice in areas where hail is common or on roofs where high foot traffic is expected.
Using polyurethane to extend the life of an existing roof is relatively uncommon because installation emits a nearly intolerable chemical smell. It is recommended that building operations be suspended when applying. A more typical application would be fortifying other commercial roofing systems during construction.
Silicone Roof Coatings
Silicone roof coatings are the most durable and versatile roof restoration materials available and are a popular choice for re-finishing almost any commercial roof type. Silicone’s exceptional resistance to ponding water is the main reason for the coating’s prevalence. The material stands out for its UV protection as well. Reflecting 80-90% of the sun’s UV rays dramatically reduces energy costs for building owners during the summer and lessens wear and tear on HVAC systems.
These benefits make this particular material the most prevalent coating choice to withstand the harsh climate of Florida and the rest of the Southeastern United States.
Silicone roof coatings are a near-perfect solution for our region, but the material also has a few negative attributes that should be considered. First, the material attracts dirt that can accumulate and lessen the UV reflectiveness of the coating. This can be mitigated by a light pressure washing annually. Additionally, the material’s resistance to water makes it very slippery when wet. If you expect high foot traffic on the roof, a silicone roof coating may not be the best solution for your building. There are types of aggregate, like sand, which can be mixed into the coating to provide slip resistance.
PMMA Commercial Roof Coatings
PMMA coating is a newer technology, which is installed as an integral part of a new roof system. Due to the material’s relatively high cost, it is more commonly used to fortify a roof during installation to withstand a heavy payload like pavers or a rooftop garden. In addition to providing strength, the system offers a high degree of resistance to water and exceptional UV protection as well. We have installed PMMA systems on dead-flat roofs with pond water, and they have performed very well.
PMMA coatings are typically a catalyzed, reinforced system. The liquid material is mixed with an activator to allow the material to harden quickly. The application process consists of a base coat of liquid, followed by an impregnated fleece material, and lastly, a finish layer of liquid. The fleece reinforcement provides strength for the system to not crack and fail over the lifespan of the roof system.
Should You Coat Or Replace Your Commercial Roof?
Three main factors weigh into the decision to coat or replace the commercial roofing system on your building.
The first, and possibly most important, is the condition of your roof. Coatings can help extend the life of a roof that only shows minimal damage or wear. If a roof has significant structural membrane damage or is saturated with water, coating it will not be a viable long-term solution.
The second factor is the age of your roof. Coating a roof is an excellent option to ensure it achieves its expected life based on a warranty. If the roof is already over 20 years old, it makes sense to replace it instead of putting a band-aid on it only to tear it off and replace the whole system in a few years.
Finally, your budget always impacts decisions related to your building’s roof. Applying a coating is less expensive than replacing it in most scenarios, but it is not a permanent solution. At some point, you will have to install a completely new roof, so consultation with a qualified roofing contractor will be necessary to determine if you are actually saving money or simply delaying a big expense.
Register Roofing has been applying coatings to extend the life of commercial roofs for decades. If you’re noticing premature issues with your roof, let our experts assess the situation and determine if a commercial roof coating is the best option for you.