For years, a home’s energy efficiency has been assessed based on the amount of heat loss and permeation through the sides of the property—via windows, doors, and foundational cracks. Now, roof manufacturers are starting to reevaluate this issue from the top-down by looking at the vulnerabilities of common residential and commercial roofing materials, like asphalt shingles.
Most property owners, on the other hand, are not as mindful of their roof’s energy efficiency, and it often leads to increased energy and maintenance costs. For example, darker roofs are a popular choice, particularly among residential homeowners, because of their aesthetic value and ability to instantly improve curb appeal; however, during the warmer months, these roofs conduct more heat. As a result, the surface temperature of the entire system rises to unsustainable levels, leading to quicker discoloration and depreciation.
To reduce the harsh heating effects of prolonged sun exposure, many new roofs are coated with a layer of reflective pigments that improve their solar emittance and reflectance. These cool roof systems come in numerous styles, include low and steep-sloped designs, and are often white or lightly shaded to reduce heat conduction. This reduction in surface temperature prevents heat from permeating your home and driving up your air conditioning costs. Cool roofs will also improve indoor comfort for your friends and family while cutting down on your maintenance expenses.
It is important to note, though, that cool roofs have several design-induced flaws. Cool roofs are exactly that: cool; these systems are not equipped to optimize your home’s heat retention during the colder months since their engineered to deflect visible, ultraviolent, and infrared heat signatures. Before you install a cool roof, make sure you’re prepared to spend more to heat your home. Also, as previously mentioned, these roofs are often white or lightly colored, so they’re likely to become dirty quicker than darker roofs. As cool roofing technology has advanced, some manufacturers have started creating energy-efficient systems with dark shingles installed over the reflective coating layer, so be sure to ask your roofing contractor about their customization options during the consultation phase.
If you’re looking for a cool roofing solution that is less reliant on synthetic coating, another popular alternative is a green roof. These systems have a top layer of vegetation that shades the roof’s surface, which reduces heat retention, air pollutants, and greenhouse gas emissions. You can find a lot of grand examples of green roofs complete with full gardens and rows of towering trees. Those are typically found atop large commercial properties, but a green roof can be as simple or ornate as you wish; at minimum, all you need is a two or three-inch ground layer.
Green roofs are excellent options for residential and commercial properties, particularly in urban areas that experience the heat island effect, or hotter conditions brought on by a lack of moisture and shade due to heavy industrialization.Cool and energy-efficient roofing is merely the latest front in an ongoing push for innovation. Roofing technology is being advanced every year, so it’s key to work with a roofing contractor that will keep you in the know during your renovation project. Whether you’re looking for replacement roofing in the Quad Cities or you simply want reinforce your current system because you live on the coast, the best way to get the most precise appraisal of your home’s energy efficiency and thermal control needs is to consult a professional remodeler. Taking this step will bring you a little closer to answering the all-important question: Is your roof cool?