What is a Cool Roof?

What is a Cool Roof?
Cool roof

Cool roofs can also benefit the environment

Cool Roofs

Are you interested in learning more about cool roofs? No, not “that’s a really cool looking roof” kind of roof. These are specially designed to reflect more sunlight than the average roof, hence absorbing less heat. As you may suspect, this comes with plenty of benefits.

A traditional dark roof can reach temperatures of 150º F or higher when exposed to the summer sun. However, a cool roof under similar weather conditions can stay more than 50° F cooler. This stark contrast roof temperature helps property owners in the following ways:


  1. – reduce their energy bills by decreasing the amount of air conditioning that is needed
  2. – consistently lower roof temperatures can extend the life of the roof and reduce thermal shock
  3. – rooms that are not air conditioned, like a garage, will be kept at lower temperatures
  4. – reducing power plant demand can also lower the risk for outages


Cool roofs can also benefit the environment, and not just by reducing energy usage and power plant emissions, though those are definitely great thing as well! If communities make a concerted effort to convert to cool roofs, local air temperatures can be reduced, improving air quality and slowing the formation of smog.


So, What Makes a Roof Cool?

What makes a roof cool is the surface material that is used on the roof. For instance, low sloped roofs can use single-ply membranes that are pre-fabricated sheets of PVC that reflect sunlight. Built-up roofs are another option, which are also sometimes referred to as tar and gravel roofs. They are converted to cool roofs by using reflective marble chips or gray slag rather than dark gravel.

The good news is that you don’t have to install a new roof. You can make an existing roof cool by choosing the right surface. Just as you wear white in hot weather to stay cool, existing roofs can be coated with such as silicone or special reflective pigments that will reflect sunlight. So, if the prospects of a white roof isn’t appealing, there are other colors to choose from as well as materials.



While installing a cool roof may seem like a no-brainer, you need to consider certain factors, such as the weather conditions in your area, before you move forward.

Cool roofs are ideal for warm or hot climates. But for those of us in the Pacific Northwest, roofing materials that are used need to keep our cold and damp conditions in mind. The moisture from condensation may result in eventual material degradation. It’s possible that cool roofs are more susceptible to accumulating moisture than dark roofs that are otherwise the same design.


If you live in the Portland, Oregon area, Pacific West Roofing can help guide you on your path to making your roof a cool one.

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