Friday, July 31, 2009

The Power of a White Roof

The New York Times ran a front page article about the energy savings of putting a white roof on a home. Evidently, white roofs which cost fractionally more than dark versions, can reduce air conditioning costs by 20 percent or more in hot sunny weather. The white EPDM torch down roof on the Oak Beach project is part of what earned it a perfect score on the H.E.R.S. scale (Home Energy Rating) by Energy Star. True, some renewable energy systems can be costly (photovoltaic, wind turbines, biodiesel) but clearly a white roof combined with efficient windows and proper insulation can be a cost effective way to reduce energy consumption. In fact, some scientists believe that if all of the world's roofs were white, it could save the equivalent of 24 billion metric tons in carbon dioxide emissions. Of course in cold climates, the roofing may not be as beneficial since heating costs outweigh cooling; however 'cool' roofing seems to be a logical trend in energy efficiency that's gaining some traction.


modernemama said...

If all commercial buildings had white roofs it would make a significant impact. When the hot mop asphalt goes on our flat roof (probably 5-10 years on this sort of construction) I will definitely white EPDM it.
PS Siding looks awesome on the house, great contrast with the roof... but is there an energy rating for different colored shingles?

Nadine @ BDG said...

Good question! I'll have to look into that.

Stan said...

Other than looks I never could under putting dark colored roofing on houses since it absorbs so much heat. White makes perfect sense. Except when it gets older, stained and dirty.

cluny said...

The color of siding has no impact on a home's energy efficiency, just the roof, as that is where the most sunshine is absorbed. And please forgive me, but the EPDM is glue down, no torches involved.
The house has been enrolled in the RELI annual Solar House tour. This is a national day of support and education for the use of PV's and other solar design elements. check out the website if you are interested