How does a reflective roof coating make a commercial roof “cool”?
Is your building’s roof a “cool” roof? What does having a “cool” roof even mean?
July is just around the corner and it’s heating up across the Lou. A busy business owner doesn’t have time to dip their toes in the local pool. There’s work to be done, clients to meet, and money to be made while dipping in and out of AC-chilled interiors. You grab the mail on the way into the office and open your energy bill for the month. Wowza! You’re paying the equivalent of a small car loan to keep your office building cool each month. How do you keep your building cool without paying a small fortune?
You need a cool roofing solution for your commercial building. We call it a solution for a reason: paying too much for your AC is a problem that needs a solution. So, what is a cool roofing solution?
Virtually any commercial roof can be converted into a cool roof by applying a reflective coating. ENERGY-STAR defines a cool roof (or reflective roof) as having 65+% reflectivity and 50+% of emissivity after three years of aging. (ENERGY STAR) While the reflectivity rating is important, the emissivity rating may be even more important.
What does emissivity mean? A material, like metal, tar, and even SPF, has a special rate that it emits the radiance of the sun’s UV rays. If you leave a metal shovel out in the sun, the wooden handle may be a little warm to the touch but the metal part of the shovel may be much hotter, even burning your hand if you touch it. That’s because the wood naturally emits (releases) more of the sun’s radiance while the metal retains the radiance.
Let’s take that concept and apply it to commercial roofing. If you have an all-metal panel roof, your building is far more susceptible to letting the metal panels conduct the sun’s radiation into your building’s interior. This is because the metal has a low emissivity rating, which means that metal holds onto heat longer than most other materials.
Adding a covering of Spraying Polyurethane Foam (SPF) onto your existing roof surface creates a natural barrier against the sun’s radiation. This means your building is less likely to retain and conduct the sun’s heat into your attic and office space. By adding an acrylic-based reflective coating on top of your new SPF roof, you have increased reflectivity and emissivity to keep your building cool through the blazing days of summer.