White is the best color for energy efficiency due to the albedo effect. With a white ceiling or a ceiling with a color that has equally lighter tones, the sun's rays are reflected rather than absorbed. If all materials are the same, lighter ceilings (such as white, light gray, and light brown) tend to have a higher reflectivity index. A reflectivity index isn't the only measure of a roof's energy efficiency, but it's a good starting point.
While you won't be able to check the reflectivity index of your roof on your own, a roofing professional will be able to provide you with the information you need. If you want to increase the energy efficiency of your roof, it may be useful to use paint or coating for the ceiling. Some ceiling coverings make the ceiling a lighter color, such as white, or will use special reflective pigments that reflect sunlight. For example, a study found that a white roof was 4.62% colder on a hot day in Arizona than a non-white one.
In addition, during the hottest part of the day inside the building (5 in the afternoon), a white roof was 8.49% colder than a non-white one. According to research conducted by the Lawrence Berkeley National Laboratory, increasing the SRI from 25 to 40 can lower the roof temperature by more than 13 degrees. This reduction can result in savings of 15 to 20% on your electricity bill. Metal roofs tend to have a high reflectivity index and dissipate heat naturally.
According to researchers at the U.S. Department of Energy, metal roof panels or shingles can reduce cooling costs by nearly 25%. When it comes to color, light-colored metal is generally a more energy efficient roof option than dark-colored metal roofing. However, the reflectance of the shingle roof depends primarily on its color.
For example, red clay can only reflect 20% of solar energy, while white clay tiles can reflect up to 70% of sunlight. A light-colored roof absorbs less heat through the roof during summer. As a result, air conditioning works better, consumes less energy and reduces utility bills. On the contrary, a dark-colored ceiling will most likely warm the highest rooms in the house.
Your cooling system works harder to compensate for additional heat, driving up your bills. When it comes time to choose a ceiling, lighter ceilings work better than darker ones. However, there is no specific color that best suits your energy bills, since good insulation is what makes the difference in the amount of heat that enters your building. Your roof protects your tenants and their possessions, their investment and (if done correctly) their energy bills, especially in hot, desert climates like Las Vegas.
In general, roofs with higher reflectivity indices (more than 65%) reflect the sun's rays better and keep the house cool during the warmer months. Energy efficiency is important, but you'll need to choose a roofing material that also fits your other criteria, such as cost, quality, and durability. There are a variety of roofing materials to choose from, and some lower energy costs better than others. Popular roofing materials that can increase energy efficiency include metal options, composites and some asphalt options.
If you plan to opt for composite roofs, choose a light color for the highest level of energy efficiency ceiling. Depending on the type of roof you choose, you may only need to include an air gap, as the insulation could allow mold or mildew to grow. However, while this commonly used roofing material is affordable and durable, its energy efficiency levels differ dramatically between products. Energy-saving roofing materials, such as slate, ceramic, stone, or concrete shingles, will absorb and retain heat and emit heat inside the roof cavity.
A professional and reputable roofing company can help you decide which energy-efficient roofing material is best suited for your home, situation and region. A dark-colored ceiling can reach temperatures much higher than the outside air temperature, sometimes up to 90 degrees. .