White roof savings

NY Times:

Returning to their ranch-style house in Sacramento after a long summer workday, Jon and Kim Waldrep were routinely met by a wall of heat.

“We’d come home in the summer, and the house would be 115 degrees, stifling,” said Mr. Waldrep, a regional manager for a national company.

He or his wife would race to the thermostat and turn on the air-conditioning as their four small children, just picked up from day care, awaited relief.

All that changed last month. “Now we come home on days when it’s over 100 degrees outside, and the house is at 80 degrees,” Mr. Waldrep said.

Their solution was a new roof: a shiny plasticized white covering that experts say is not only an energy saver but also a way to help cool the planet.

Relying on the centuries-old principle that white objects absorb less heat than dark ones, homeowners like the Waldreps are in the vanguard of a movement embracing “cool roofs” as one of the most affordable weapons against climate change.

Studies show that white roofs reduce air-conditioning costs by 20 percent or more in hot, sunny weather. Lower energy consumption also means fewer of the carbon dioxide emissions that contribute to global warming.

What is more, a white roof can cost as little as 15 percent more than its dark counterpart, depending on the materials used, while slashing electricity bills.

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Actually there was no difference in price when I installed a white metal roof. I probably could save some money by going with the silver Galvalum finish which actually reflects even more heat. I also installed a reflective barrier inside the roof as well as super insulating the ceiling and walls. The results was remarkably efficient. We just had one of the hottest Junes since I have been living here and my electric bill was a little over $200 for a 2,500 square foot house.