Does My Roof Need To Be Coated?

So your home inspector or contractor recommended you coat the flat roof on your home, but you aren’t really convinced it makes a difference. You’ve come to the right place to find out! (See also Can my roof be repaired? And Roof Repairs and Tune-ups)

First off, do roof coatings make a difference in extending the life of a roof?

The answer to that question is 100% yes. Roof coatings come in a variety of colors and materials, but generally they are at least reflective and sometimes contain materials to moisturize the roof membranes. If you have a metal roof then an asphalt based coating is terrific at warding off rust, which is the biggest enemy of metal roofs.

There’s many types of roofs and how much a coating can help depends on your roof type. In Washington DC the majority of flat roofs are Modified Bitumen, EPDM, TPO or standing seam metal. So knowing how much it will help, and in what ways, you need to identify the material your roof is made out of. See Roof Types in Washington DC for help.

On modified bitumen roofs a coating can prevent premature surface cracks and delaminating of the membrane. It also adds back some oils to the membrane to make it less brittle as it ages.

Sometimes a roof can benefit from a coating due to poor drainage situations. When ponding water occurs on a roof the best option is almost always to eliminate the ponding water, but this isn’t always possible due to budget constraints or even poor drainage due to design flaws. In these cases, a coating that resists ponding water, like a pure silicone coating, can be the best course of action.

Will coating my roof help with energy efficiency?

This one depends on a few factors, but the answer is usually a yes. We recently had a client who had a 4 story row home in Shaw and they complained of their top floor being hot on warm days, even with the AC running full blast. We checked the roof and sure enough it was a new modified bitumen roof that wasn’t coated and so was the natural black color. We recommend coating the roof with asphalt aluminum roof coating as a first step. The next step would be to add some spray insulation between the ceiling and roof deck, but since this was a recent renovation they’d built it without access to the crawl space and that would be a more expensive and difficult task than a regular house.

We took some temperature readings on the roof surface the day we coated it. The outside temperature was 85F with full sun. At 10AM the roof surface read a toasty 155F, but after coating the roof and taking the temperature at 12noon, it read a full 70 degrees cooler.

We are big believers in coating and sealing roofs, because if you can extend the life of your roof it’s good for your wallet and it’s less roofing materials in our landfills so it’s good for the environment too. Of course not all roofs can be coated, some are just too far gone, but we can take a look and help you decide if you need a coating or Full or Partial Roof Replacement. Call us today!