As the temperatures are rising in Massachusetts, you are probably doing everything you can to stay cool. Running the air conditioning and fans in your home are often not enough to escape the heat. The sun beating down on your roof can cause its temperature to rise. According to the Department of Energy, on a sunny day the temperature of a traditional black roof can be 50°F warmer than the air temperature. When dealing with this warm climate, it would be beneficial to know how to cool your roof in the summer.
What are Cool Roofs?
Cool roofs have been designed to reflect more light and absorb less heat than traditional roofs. They have a high emissivity, which means that they emit infrared energy. They can be made of a sheet covering, highly reflective paint, or highly reflective tiles or shingles.
Benefits of Cool Roofs
There are many benefits to having a cool roof placed on your home or building. It allows you to save on electricity bills by decreasing the use of air conditioning. Also, it improves the comfort inside a home that isn’t air conditioned. High temperatures cause shingles to expand and contract, causing cracks in their surface. A cool roof can help prevent this damage, extending the roof’s life.
When there are many buildings in a small urban or suburban area, air temperature can feel higher than it is. This is called the”heat island effect.” If buildings in a tight area replace their roofs with cool roofs, then it can reduce the air temperature around them. Also in these areas, these roofs can lower peak electricity demand which will help prevent power outages. Cool roofs reduce cooling energy use in buildings, which in turn reduces power plant emissions such as carbon dioxide and mercury.
Types of Cool Roofs
Cool roof coatings are white or use reflective pigments that reflect the sunlight, rather than absorb it. They are thick paints that protect the surface of the roof from UV rays.
Which materials you use for your cool roof will depend on the slope of your roof. Flat or low sloped roofs have a few options for materials. The first option is single-ply membranes that are used to reformulate or coat black membranes to make them reflective. Next are built up roofs that consist of base sheet, fabric reinforcement layers, and a protective surface layer. They can be made cool by using reflective mineral granules of factory applied coating instead of a dark coating, or by applying a cool roof coating on top of the dark asphaltic emulsion coating. Modified bitumen can be made cool by pre-coating it with a cool roof coating. Lastly, spray polyurethane foam roofs rely on a protective coating that is already reflective, which allows them to perform as cool roofs.
Steep roofs can use tiles and shingles to make them cool. Tiles can be made of slate, clay, or concrete and some are naturally reflective enough to perform as cool roofs, or they can be coated with surface treatments to transform them into cool roof material. You can buy cool asphalt shingles that use specially coated granules, or you can buy wood, polymers, or metal shingles that can be coated to make them more reflective. GAF Timberline® Cool Series Shingles, as shown in the image above, can provide potential energy savings and cost savings when you install them on your roof.
When you are deciding whether or not a cool roof is for you, you should weigh out the cost with the energy savings. Then you need to decide if you want to install a cool roof to a new construction home, coat an existing roof, or replace an existing roof with a cool roof. If you have any questions, please contact All Weather Tite in Marlborough, MA. We will be happy to give you a free estimate on your new roof.