With the temperatures here in Los Angeles starting to creep up and the summer months lurking just around the corner, I got to thinking about something that I had heard about a few years back. White Roof?
From Energy Secretary Steven Chu in a CNN report back in 2009, “Whitening the world’s roofs and roads would have the same effect on global warming as removing all the world’s cars for 11 years.”
From Bill Clinton’s Newsweek piece titled, “It’s Still The Economy, Stupid”, June 2011, he had this to say – Look at the tar roofs covering millions of American buildings. They absorb huge amounts of heat when it’s hot. And they require more air conditioning to cool the rooms. Mayor Bloomberg started a program to hire and train young people to paint New York’s roofs white. A big percentage of the kids have been able to parlay this simple work into higher-skilled training programs or energy-related retrofit jobs. (And, believe it or not, painting the roof white can lower the electricity use by 20 percent on a hot day!)
Proponents of the idea tout other advantages—reflective surfaces also reduce temperatures in urban “heat islands,” and reduce the need for air-conditioning, which in turn reduces the demand for electricity, which generates its own greenhouse-gas emissions.
Mayor Bloomberg in New York said this “It’s such a simple concept—anyone who has ever gotten dressed in the summer knows it—light-colored surfaces absorb less heat than darker surfaces do,” Bloomberg said from a factory rooftop in Long Island City. “Coating rooftops with reflective, white paint can reduce roof temperatures by as much as 60 degrees and indoor temperatures by 10 to 20 degrees.” Gore thanked the mayor for keeping the city “at the forefront of enacting innovative policies that reduce our carbon footprint.”
So, can painting roofs white save you money and cut down greenhouse gases? I believe it can.
According to Chu white roofs have three major benefits:
1. It keeps buildings cooler, reducing the amount of energy required for air conditioning.
2. It reduces the so-call “heat island” effect, the heating up of entire urban areas which then causes other buildings in the vicinity to heat up, whether they are in direct contact with the sun or not.
3. A white roof or road will actually reflect the sun’s rays back into space, keeping the atmosphere cooler.
You might wonder what about the colder climates where one might think that a black roof would provide a heating benefit during the winter months?
There are several factors that say any winter heating benefit would be minimal:
In winter months -
- the angle of the sun is less direct, which also helps to minimize warming potential.
- many roofs are covered with snow for much of the winter, turning them “white” and eliminating any potential black roof heat gain.
- the energy required to air condition a building in the summer is usually considerably greater than the energy to heat it in the winter, making the potential for summer energy cost savings much greater
- white roofs can provide more than just energy savings
- a white roof saves money on roof repairs. Since black roofs become overheated in the sun, they are prone to warping and cracking. This means more roof repair. A white roof saves money on roof repair because it is more durable. A white roof can also extend the life of a buildings cooling equipment by decreasing use.
I am not saying that you must go out and replace or paint your roof, but if you’re doing new construction or in need of an upgrade, a white or lighter colored roof is a Green Alternative to the black asphalt shingles.
For more information on White Roofs, Materials, etc.. Cool Roof Resources
Something to think about!
Until next time, I’m the Go Green Guy saying “Think Green! Live Green! and Go Green America.”
About the Author (Author Profile)
Creator/Host of Go Green America TV
Jeff (Jf) Davis aka The Go Green Guy is from Maine
Moved to LA to follow his passion as an actor
these days he is still acting, lives in LA with his wife and two boys
an writes about Green Living for his website Go Green America TV
that will soon be a TV show!!