Reflective roof paint repels the heat (as do lighter colored asphalt shingles - forget the black!)

[lindisfarne]

On bright days, the rooftop of the Anaheim Hilton is so blindingly white that it looks like a mirror positioned directly at the sun. That dazzling glare might just be the greenest thing to happen to the top of a building since solar panels.

The white coating deflects nearly 85% of the heat that hits it, reducing the surface temperature by as much as 50 degrees. That means less energy is needed to cool the hotel's interior, cutting air-conditioning costs and carbon emissions.

This is no ordinary coat of paint. Designed by an 82-year-old former military scientist from the Inland Empire, the tinted topcoat is filled with tiny hollow glass balls that deflect heat, layered over a waterproof undercoat made of recycled rubber.
...
His Hyperglass top coat is designed like a Rice Krispies treat. Glass "microspheres," which are used to lighten airplane parts and bowling balls, are suspended in a paint that includes Teflon. The whiter the titanium dioxide tint, the more heat bounces off.

Underneath, his Hyperflex primer serves as an insulation layer that also helps prevent water damage and erosion. And because it uses powdered recycled rubber, it helps address another thorny environmental issue: the millions of tires discarded annually in the U.S.
...
Hyperseal paints are free of harmful volatile organic compounds known as VOCs and are relatively cheap to produce, but the company's Palm Desert factory can make only 5 million gallons a year. Most large projects, such as bridges, require several hundred million gallons, Savin said. So he's looking to license his formula to other companies.
http://www.latimes.com/business/la-fi-cool-roof15-2009jul15,0,2823772.story

[Grown2Hate]

1. My only concern would be what my stupid ass HOA would have to say

about it. If I can do this, living in Arizona, I'd jump all over it!

[lindisfarne]

2. Some states have passed laws preventing HOAs from stopping people from doing this.n/t

[Abq_Sarah]

4. HOAs are a problem

For people trying to cut energy bills by installing cool roofs/coatings.

I was glad to see this stuff is compatible with steel/metal roofs since that's the most common roof type in use here. I'd hesitate to use it on a flat roof with an adobe/fake adobe house in any area that gets significant snowfall.

[BonnieJW]

7. I grew up in Tucson

and back in the 60's when my parents built their house, the roof had a final layer of white marble chips. The sun reflected off the chips and kept the house cool. This is not new technology.

[hatrack]

3. BTW, if you're having to re-roof this year, you can get a tax credit for EnergyStar shingles

We had to have a tear-off done (most of it covered by insurance, providentially) and discovered this great deal.

You get a credit equal to 30% of the cost of your shingles, which are typically about half of the total cost of a roofing job, maybe a bit more depending on the size of your house.

http://www.84lumber.com/energy/PDF/GAF_Shingles.pdf

[AZCat]

11. Depending on your location, you might get more than that back.

In Tucson, for example, the local electrical utility (Tucson Electric Power) has federal dollars set aside for rebates for energy efficiency upgrades to homes and business.

[TankLV]

5. well DUH...sort of like "ice cubes help cool things"...department...

I'm referring to the "white" reflects heat statement...while black absorbs it all...

[lindisfarne]

6. Yes, the "new" thing is many folks, including energy Secretary Chu, are saying to use light colored

roofs. Look around you - how many dark roofs in your city? Maybe it's important to say this?

[The Croquist]

8. Agreed!

I put the lightest shingles I could find on my roof (in Georgia) almost 20 years ago.

It was a no brainer...

[rgbecker]

9. Just a slightly different view from up, New England, way.

No a/c at my place and no energy costs because of heat...on the otherhand, any heat I can get out of the sun from October to April is welcome and a black roof is my answer. Just saying.

[The Croquist]

10. No argument

Think globally, act locally. When in doubt, save money.

[JDPriestly]

12. Our next-doortr-neighbor was just visiting our house today (near

downtown L.A., CA) and noted how cool it is. We don't have air conditioning. We have light-colored tiles on the roof, light paint on the wood shingles, lots of windows and lots of trees. We keep the windows open at night (those high enough off the ground so that no one could get in without our hearing them, but keep the shades closed during the day. We keep surprisingly cool.

And if all that doesn't work, try washing your feet and face in cold water. Might help.

[Kolesar]

13. Great post

I put ice packs on my knees.

Note that white shingles have an asphalt layer that still absorbs 80% of the sun's energy. We bought a Dupont Cool Roof membrane roof that reflects 80% of the heat.

Roofers will plunge their feet into buckets of ice water. After they remove their shoes and socks, of course.