Part 3: Application Concerns When Applying Roof Coatings
Application Concerns When Applying Roof Coatings
By Dave Lubach, Associate Editor August 2014 - Roofing
Rooftop temperatures and moisture are two key issues for managers and technicians to consider during roof-coating application. Standard procedures call for ensuring the temperature is at least 40 degrees and applying coatings at least 24 hours before rain is forecast.
"If you (apply) a water-based coating and it rains an hour later, you could have a big mess," Martucci says.
In the case of high humidity, "water-based coatings such as acrylics cure slower and cannot be applied year-round in many areas," says Van Ripps of Palmer Asphalt Co. "Silicone coatings are a growing product segment for roof coatings and are moisture-cure coatings that can be used year-round."
Determining the proper thickness for application purposes is also important. A guideline for managers is 20 mils of dry thickness, Martucci says.
"The biggest mistake is putting it on too thin," he says. "You want a quality coating that when it cures and dries, what you're left with is the solids.
"If you have a watered down coating with a low solid content, what you're going to be left with is a thin film. And that's not enough to protect the roof. You want to make sure they have enough protection on the roof that it's put down at the manufacturers' specification."
Training front-line technicians on proper techniques for applying roof coatings can help managers meet such goals.
"Proper training of the application crew is critical to ensuring that a roof-coating project is completed correctly," Baumann says. "That training should include such topics as how to choose the right products for the specific application, proper coating-application techniques, the importance of not applying coatings on windy days to ensure that nearby parked cars do not become coated, and the personal protection equipment that crews should employ."