Tips for Successfully Installing Liquid Roof Coatings

The basic elements of applying a roof coating may initially sound so simple that explanation seems unnecessary: clean, spray, let it dry. At Energy Seal, we’ve found it’s more complicated than that – the key to success is in the details. In this post we expand on those fundamentals to help you make sure that the coating you choose will protect your roof and your building for years to come.

1. Clean the roof comprehensively with the right equipment.

Most people would say this step is too obvious to even mention, but this process requires a cleaning far beyond what most people associate with that word. The roof should be pressure-washed at a minimum of 1,500 PSI (pounds of force per square inch). This isn’t strong enough to remove stains caused by, for example, oil, but it’s more than enough to remove the kind of grime and random substances that normally accumulate on a roof over time. If those aren’t removed, the roof coating may adhere to them instead of the roof itself.

We at Energy Seal recommend using Acu-Wash, a detergent surfactant, applied with a roto spray tip, followed by a thorough rinse. The roof should be completely dry before the application process begins, which may require as much as 24 hours.

2. Check your local weather report.

Water, whether lingering from the cleaning stage or falling from the sky, can wash a roof coating away before it can adhere. No one can predict the weather perfectly, but you can improve your odds of success by scheduling your coating for a week in which no rain is expected. Manufacturers design coatings to be applied in two layers, each of which needs to set, or cure, thoroughly, for a period of time that varies among products.

In fact, the coating is so sensitive to moisture that we recommend starting the application as early in the day as possible so it has more time to dry before dew settles overnight. It’s also important to consider the humidity level in your area when you’re planning. Where humidity is high and temperatures are relatively low, you may have to wait longer between the two coats.

But temperatures that are too low can also threaten a successful installation. If a coating freezes before it sets, it may fracture into a network of cracks resembling a spider’s web, which, obviously, will not provide effective protection. 

3. Maintain the same thickness across the entire roof.

The first “step” to guarantee a consistent millage, or depth, is walking at a steady pace during the application. The crucial element, though, is frequent pauses to measure the thickness with a wet film gauge. 

To use the product Acu-Shield as an example, the manufacturer specifies that the wet film thickness of each layer should be at least 20 wet mils for each coat and each of the two layers should be allowed to cure for 24 to 48 hours. This is important not only to get the maximum benefits from the coating, but also to keep the product’s warranty in force. 

4. Seal all seams, flashings, and fasteners completely to prevent leaks.

We recommend sealing with a combination of both Acu-Caulk and Acu-Fabric. The result resembles a practically impenetrable bandage. Acu-Tape is useful for sealing flashings and seams.

Energy Seal experts don’t just have the facts about the products we sell – they also have the kind of knowledge that only comes from first-hand experience. Whether your questions are about installing a roof coating yourself or arranging for us to install one for you, we’re here to help.