Courtesy Dicor Corporation
Just like painting, much of the work in coating an RV roof is in the preparation. Roof coating is a multi-step process, beginning with lap sealant replacement or touch-up performed one to two weeks ahead of the actual coating. This will allow the sealant to be well-cured before the coating covers it, helping the sealant and coating to bond with maximum effectiveness. In the same vein, peel-and-stick patches are best applied one or two days before coating.
Next comes cleaning. A very clean surface is key to making any coating stick well. First, sweep any loose dirt, debris, sticks, stones or leaves from the roof. Then use the appropriate Dicor Products cleaner/activator for your kind of roof and for the coating system you are using.
The type of roof you have will determine the type of coating system you will be applying to the roof surface. Each roofing material has its own individual characteristics that require a certain type of coating system. Because of this, Dicor Products offers three coating systems: one for EPDM and TPO, a specially formulated roof-coating system for fiberglass, and a metal roof-coating system.
Tip: Mask off sidewalls. For the cleaning and coating procedure, I always mask off the sidewalls and caps of the RV with a good-quality tape, such as FrogTape. The cleaning/activator agent is designed to loosen dirt from the roof material. The chemicals in the cleaning and coating materials are made for the particular roof material they are acting on, not for your sidewalls and end caps. Masking off the sidewalls and front and rear end caps takes a little more prep time, but then you don’t have to keep constantly rinsing the walls and end caps (unless you like the exercise). This prevents the dirt, debris, and cleaning agent from having an opportunity to affix themselves to the sidewalls and end caps. It also prevents any accidental contact with the coating and these surfaces. It’s easier and safer all the way around.
Even bigger tip: Read the instructions! Before starting anything (listen up, guys), read the instructions! Different cleaning and coating formulas are made for different roof materials. I have been mostly talking about EPDM and TPO roofing here, but there are materials, processes, and products designed for fiberglass and metal roofing as well. Such instructions can help you make best use of your time and your product.
As for your tools, I find a medium nap roller is the best way to apply the coating material.
[Editor’s note: This information is provided by roof membrane manufacturer Dicor. While there’s plenty of "promotion” for their product included, some of the information and principles may be of assistance to our readers.]