How Much Cooler Is A White Roof

In fact a high end kynar 500 white metal roof is energy star rated and classified as a cool roof by the cool roof rating council.

How much cooler is a white roof.

False white roofs attract and retain dirt easily which quickly diminishes some of the positive aspects of the membrane. During the maximum internal temperature increase hours of 7 00am 5 00pm a white roof is 6 97 cooler more energy efficient than a non white roof. The 50 year life cycle cost analysis found that even the most inexpensive kind of green roof with no public access and consisting of only sedum or prairie grass costs 7 per square foot more than black roofs over 50 years while white roofs save 2 per square foot compared to black roofs. Similarly if your roof experiences winter problems like ice dams your roof color probably isn t the primary culprit.

Switching to a white roof can actually reduce energy use by about 20 percent in hot sunny weather according to the lawrence berkeley national laboratory heat island. A cool roof under the same conditions could stay more than 50 f cooler and save energy and money by using less air conditioning. Unless routine maintenance and power washing is completed a white roof will often dull and look. However and here is the big kicker a properly ventilated attic space let me say that again properly ventilated was a 2 degree average difference.

So although your building may be cooler it s not doing much to decrease global warming. The benefits of a white roof. What they found was surface temprature hand to shingle was approximately 20 degrees warmer if black. The question is by just how much.

Standard or dark roofs can reach temperatures of 150 f or more in the summer sun. Atmosphere a white roof should act like a natural anti warming device while also reducing your energy costs by keeping your house cool in the summer. They built test houses white roof vs black roof. White roofs will stay white.

Dark roofs may have a small snow melt effect but not a sizeable one. In cooler climates think detroit or toronto the issue is less straightforward. Some scientists say white roofs can increase heating costs more than they save on a c costs. During the hottest point in the day inside the building 5 00pm a white roof is 8 49 cooler more energy efficient than a non white roof.

Turns out painting your roof white would be. The white powder actually reflects away much of the sunlight so the dark roof underneath cannot absorb heat and melt the snow.