Mobile homes tend to overheat in summer because they don’t have a large attic space to provide a buffer between the hot outdoors and the living space inside. In many mobile or manufactured homes, the space between the interior ceiling surface and the exterior metal roof is less than a foot. Though a thin layer of insulation is installed in this cavity, the heat of summer tends to transmit right down into your living quarters.
One of the best ways to slow this heat flow into your home is to apply a white elastomeric “cool-roof” coating that, thanks in part to its elastic, stretching qualities, forms a weather-resistant, protective membrane. With this coating in place, homeowners can expect to see lower electric bills, lower roof maintenance costs and longer lives for air-conditioning systems.
Metal mobile-home roofs are easy to recoat. In fact, many homeowners do so every few years to ensure their roof’s longevity and water tightness. You can apply a cool-roof coating when your mobile home next needs to be recoated, or you could do it right away to reap immediate benefits. Many homeowners note that their home is cooler the same day that a cool roof coating is applied.
Cool-roof coatings can be sprayed on or applied by brush or roller, just like traditional black or silver asphalt coatings. Their performance is superior to these coatings, however, because their reflectivity (ability to reflect the sun’s heat) and their emissivity (ability to release the roof’s heat) are far greater. In one sense, the liquid application of cool-roof coatings is like the difference between wearing a white shirt and black shirt on a blistering hot day: You’ll be cooler in the white shirt because it reflects more sunlight and absorbs less heat.
Cool-roof coatings are available on numerous websites and at a variety of stores, including The Home Depot, Lowe’s and Ace Hardware.
To ensure that your cool-roof coating adheres properly, the roof surface should first be washed and any loose previous coatings scraped away. Because cool-roof coatings are water-based, they should be applied when no rain is expected for at least one day. Above all else, follow the manufacturer’s instructions. Once you have a cool-roof coating on your mobile home, and you appreciate the difference in summertime comfort, you’ll never go back to the old-fashioned coatings.
Author Chris Dorsi is a managing partner with Saturn Resource Management. He is a Building Performance Institute-certified building analyst, a heating professional and envelope professional, a Residential Energy Services Network certified home-energy rater, and is retired from the American Society of Home Inspectors. For more information about improving energy efficiency at home, go to www.srmi.biz.