Avoiding the Slippery Slopes of Roof Painting

Painting a roof is tricky business, anyone in the industry can tell you that, but the good news is that it's far from impossible. The first time I attempted to paint a roof was definitely a challenge — it was the summer of 1997 and I was approached by a McDonald's restaurant who requested that I paint their asphalt shingled roof with a specialty elastomeric coating. After some reservation, I agreed to do it.

I was right to have some reservations - it was not an easy task. The first attempt took a crew of three men over five days and three times the amount of paint we had originally anticipated. The first challenge we faced was coverage. It was particularly difficult because we could not spray the paint - or at least we didn't think that we could - without getting overspray on every car in the lot. Initially, we tried to paint by brush and roll, but found that this is nearly impossible to do since you must keep a wet edge at all times. Otherwise, you will have flashing and lap marks that can be seen from a mile away. After a bit of trial and error, we formulated a special spray technique that allowed us to successfully apply the coating. Turns out the coating was only the first obstacle; after about a year the elastomeric coating started to fade - especially the bright colors.

At that point, we began to do lab tests with the coating manufacturers to find a solution for the fading. The manufacturers make paint systems that can potentially work as a top coat over the elastomeric and last for many years. The issue here is that the system is a two-part urethane which yields a very strong and unpleasant odor. We ultimately had to nix this approach, because we had to keep in mind that our client is still running a business each day, regardless of the work being done. With a foul-smelling solvent being applied to the roof, there is no way anyone would be walking in for lunch! We eventually designed a safe, odorless system to coat the roof that would hold its color for at least five years.

At that point I thought we had this roof-painting business in the bag, after having worked out so many kinks and overcoming various obstacles. However, I had not taken into account locations that have metal roofs made of Kynar and other rolled steel. When these materials are dry, it is very difficult to get water based paint to stick to them. Off to the paint labs we went again! We were finding that many of the products out there just didn't work in the real world. After some more trial and error, we came up with a fast-drying alkyd oil-based primer. This primer is ideal because it is heavy enough that the overspray will drop fast, and it will land dry if it is blown by the wind. This system works very well and holds up to the damp adhesion test.

As a painter, my job is not only to apply the paint - but to ensure that my clients are receiving high quality products that will stand the test of time and the elements. Learning the ins and outs of painting roofs became a labor of love for me. After investing a lot of time, and after much trial and error, I can confidently say that painting roofs - regardless of the material - is possible. In the ten years since my company started including roof painting in our services, we have painted more than 3,000 asphalt shingle and metal roofs across the country and have helped many other painters and clients paint their roofs as well.