The late, great Michael Jackson once sang, "It doesn't matter if you're black or white." But when it comes to your roof, it really does matter. A black (or dark) roof absorbs heat on a sunny day--which is great in the winter--and a white roof reflects the sun--which is great in the summer. But for each roofing color, those advantages turn to disadvantages as the earth moves to the other side of the sun. The black roof turns the home into a sauna in the summer, driving up cooling costs, and the white roof reflects badly needed heat in the winter, elevating the heating costs.
Thanks to a handful of recent genius MIT graduates, the human race can now lay claim to color-changing roofing tiles. White in the hot months and black in the cold, the tiles use a technology that changes their color in response to temperature.
Bottom line figures: In their "white state," the tiles reflect as much as 80 percent of the sunlight, potentially saving up to 20 percent in cooling costs. "Black state" figures have yet to be released.
No word yet on what shade the tiles take on under overcast conditions. Rooftop mosaic, anyone?