roof coatings repair guide

The Ultimate Roof Coatings Repair Guide

When it comes to roof coating repair, the necessary steps to fixing a damaged roof coating will depend on the type of coating, its age and the extent of the damage. 

Commercial roof repair is not a one-size-fits-all solution, so it is important to educate yourself and make sure you choose competent contractors who know your roof and what is needed to protect your building.

In this ultimate guide to roof coating repair, we’re going to look at:

  • The different types of roof coatings
  • The common causes of damage
  • Best practices for repair
  • When to know it’s time to skip the repair and go straight to replacement  

Know Your Roof Coating

There are several types of roof coatings on the market, and then you also have to consider roof coatings vs. fluid applied reinforced roofing. What’s the difference? 

When people talk about applying a roof coating, they are usually referring to an application of just that, roof coatings, rolled or sprayed on usually in two applications or passes.  

A Fluid Applied Reinforced Roofing System utilizes similar roof coatings but they are applied much thicker and layered with one or more reinforcing membranes. The multiple applications and reinforcing layer gives the roof coatings superior waterproofing and strength to withstand the movement of your buildings and any harsh elements that it might be exposed to, including standing water.  

Fluid Applied Reinforced Roof Systems

Fluid Applied Reinforced Roof (FARR) systems combine the durability of reinforced polyester fabric, with the continuous seal of a fluid or emulsion roof coating. These coatings can be asphalt, acrylic, silicone or aluminum, and each offers different benefits and concerns that can affect which one you choose.

As with all roof coatings, FARR systems go on in a liquid form, which means they make a seamless membrane that protects your roof from water intrusion, while the polyester layers add strength — some FARR systems are even FM rated for hail — and the redundancy of layered applications further insures that the structure below is protected. 

While FARR systems are designed to be compatible with many types of existing roofing systems, like metal, gravel and BUR, not all coatings are compatible with all roofs. One of the leading causes of damage comes from improper application, like when a contractor applies the wrong coating over a TPO roof without a primer


Asphalt roof coating is perhaps what many people think of as a “normal” roofing material. Asphalt-based roofing materials have been used for hundreds of years, and they offer waterproofing by the thickness of application. 

Asphalt emulsion coatings are a new version of the old asphalt coatings that were heated in a kettle for hot mop application. The new formulation does not need to be heated and has almost no odor. These coatings are typically black, which means they absorb more solar energy than white and light-colored acrylics, silicone and aluminum roofs. They are designed to be top-coated with an energy-efficient coating.   


Silicone is another roof coating that is frequently recommended as an inexpensive option. Typically white in color, it’s popular with energy-conscious building owners and operators because it reflects solar energy rather than absorbing it, which reduces the energy load on building HVAC systems.

Silicone roof coatings are also advertised as a great option for roofs where ponding water is an issue, as the coating is not water-based; it can stand up to long exposure to water with less risk to the roof deck, insulation and other building envelope components below. 

Unfortunately, because silicone is slippery by nature, it also doesn’t always adhere as well as other options to existing roof systems, repair materials or to itself. Contractors often struggle to repair damaged silicone roofs because it’s hard to get adhesion over the repaired area, which risks future damage. Sometimes, the only option is to replace the roof entirely, which is costly.


acrylic roof repair

Acrylic is one of the coatings that is often used in FARR systems, but it can be applied on its own as well. Acrylic cool roof coatings are another option that is highly energy-efficient, which not only reduces energy demand in the building but also prevents premature aging of the roof.

Acrylic coatings are frequently recommended as a waterproofing option, and while they stand up well to heavy rains, some acrylic coatings may not do as well under ponding water.  Because acrylics are water-based they can begin to break down if they’re not designed to stand up to ponding water. However, many manufacturers offer acrylic coatings that have been specially formulated to last under ponding water and, with proper application, they have been proven to perform over many years of use.  


Polyurethane roof coatings provide durability and flexibility and are well suited to extending the lifespan of flat commercial and metal roofs. They can be colored to suit your needs and provide a continuous waterproof membrane to protect your building.

When choosing a polyurethane coating, make sure you understand what it is designed to do. Aliphatic polyurethane coatings are designed to be a long-lasting and protective coating on top of your existing roof, while aromatic coatings are meant to be a base layer as part of a larger project. Choosing the wrong polyurethane coating can mean premature failure of your roof.

Polyurethane coatings are also solvent-based, which helps with their waterproofness, but can also create issues around nuisance odors during application. If you’re choosing a roof coating for a building with sensitive receptors, like hospital patients or long-term care residents, polyurethane may not be your best choice.


Aluminum coating roofs are reflective. They create a reflective surface and stand up well to wear and tear from regular foot traffic.

While aluminum coatings are energy-efficient, they don’t offer the same reflectivity as acrylic coatings, so they aren’t as well suited for a building in the sunbelt with air-conditioned spaces that don’t have adequate insulation to keep out the heat. They can be an excellent lower-cost alternative for certain buildings.  

Historically, not all aluminum coatings were water-based, which made it difficult to adhere to certain substrates. However, modern formulations like 525 Silverwhite are water-based and cost-effective. 

Common Causes of Roof Damage

roof damage causes

All roofs wear over time, but the hope is that you’ve chosen a roof coating that will stand up to the most common causes of roof damage it is likely to face. Let’s look at common causes of roof damage and how to avoid them.


Water damage is often the most pressing concern when it comes to your roof, but often comes in two forms:

  • Heavy precipitation
  • Ponding water

If you live in an area that faces frequent rain, or a busy rainy or hurricane season, then you want to choose a roof coating that stands up to the weather over time. But not all roof coatings that do well in rain also stand up to the effects of ponding water. A product like silicone or specially formulated acrylic will do better in ponding water.

Solar Energy

Just like our skin, the sun’s rays can be harmful to your roof, especially if you’re located in an area with excessive sunlight and hot days throughout the year. You want to choose a reflective coating, like acrylic, that won’t absorb solar energy the way darker colored roofing materials do.

Leaks and Spills

Although it may not seem like it at first, a roof can be a busy place, even if it doesn’t have human visitors very often. Certain roof coatings are formulated to stand up to chemicals like leaking coolant or solvent exhaust from an industrial process better than others. 

While you hope your preventative roof maintenance program and pollution control equipment will prevent these kinds of leaks and spills from occurring, choosing a roof coating that will stand up to these types of chemicals will help protect your building. 

Foot Traffic

While they may seem durable, not all roofs are the same when it comes to foot traffic. If your roof sees regular traffic, perhaps from a helicopter pad, you want to know you’ve chosen a coating that will last as people come and go. Options like FARR systems, with their polyester reinforcement, are a good choice in these situations.

Extreme Weather

While it would be difficult for any roof to stand up to hurricane-force winds, if your building is in an area that is facing more and more extreme weather events, you want to know your roof will do everything it can to protect your building’s interior.

Whether you’re facing extreme weather like high winds and rain, extreme cold or hail, look for products and systems with FM 4470 Class 1 approvals. FM Approvals is the only organization in the world that tests and approves roof assemblies. An FM Approved roof means that you get a tested roof assembly and not just a collection of parts that might not work together. 

Best Practices for Commercial Roof Repair

commercial roof repair best practices

Commercial roof repair can be as simple as applying a little elastomeric cement over a localized area, or as involved as removing the entire roof system and installing a new one. One is simple, straightforward and fairly inexpensive, while the other can take a significant chunk out of the year’s capital repairs budget.

The trouble is, if you don’t do a small repair well, it can become a big problem later, so it’s worth taking the time to fully understand the extent of the damage, hire a qualified contractor and make sure they’re choosing the right materials for the job.

The first step in roof repair is undertaking a detailed roof assessment. Check obviously damaged areas, but also take a moment to inspect the roof in general. Small pinhole penetrations in a single ply overlay can create big leaks inside. A thermal scan can be an effective way of identifying if there are cracks that aren’t immediately visible.

Roofing projects of any sort pose specific health and safety risks. Make sure the contractor you choose can provide proof of appropriate working at heights and fall prevention and fall arrest training. Ask them if they understand the risks inherent to your roof in particular. For example, a silicone roof can become very slippery when it’s wet, so make sure your contractor is aware of this if you’re repairing a silicone roof.

Next, once you and your contractor have agreed on the extent and cost of the repairs, make sure they’re using products that will last for a long time and hopefully limit the risk of future damage. 

Some roof coatings require the use of a primer as part of repairs, to make sure the patch or new coating adheres properly to the substrate. Skipping this step can create even bigger headaches in the future, so make sure all repair materials are properly specified.

If the roof damage was a result of ongoing issues like ponding water, make sure you take the time to diagnose the source of the problem. Ponding water can put an unneeded load on your building’s structure, so the cause — whether it’s a blocked roof drain or a pitch in the roof that is collapsing — you want to do everything you can to prevent it in the future.

Should I Replace My Commercial Roof?

Sometimes, it may become apparent that a few spot repairs are not going to be enough to get your roof back into working order. If your roof is showing evidence of widespread aging, you may need to replace the entire roof.

A commercial roof replacement can feel like a big expensive task: A tear-off and replace involves significant disruption to your building’s tenants and workers.

Before you commit to a full replacement, make sure there aren’t more efficient and cost-effective options available to you. An aging roof can be rejuvenated with a new roof coating system, but only if you ensure the right one is selected and properly applied.

If you’re hoping to avoid a costly roof replacement, contact Western Colloid to discuss your options. We can have a complimentary roof assessment done, and suggest potential coating solutions that can extend your roof’s lifespan indefinitely – and be easy on your budget.