Lighter Roofs Could Save $1Billion USD Annually

Hmm Iin places where it snows lighter roofs will help in the summer but in the winter wouldnt it also stop then sun from helping to heat your home ?

Light colored roofs can also extend the lifespan of the roofing membrane, as less UV degradation occurs with lighter materials as the energy is reflected in stead of absorbed. Giving the roofing materials a longer life span DOES mean that less is off-gassed while the membrane is in service, and the longer it lasts means that less goes in the landfill and less needs to be manufactured to replace it.

majortom-
I live in Iowa and in temperate climates you'll have enough insulation in the attic to keep the house energy efficient that it doesn't matter what color the roof is for winter or summer.

I had this thought about 10 years ago... I know some people were aware of global warming, but far more take it seriously today.
I was just thinking "It's damn hot on this roof... why is it black? Someone should be fired for this. ...out of a cannon into the sun!"

We made a similar suggestion as an entry to the 2008 Buckminster Fuller Contest. See http://challenge.bfi.org/application_summary/34#

Well, AFAIK, heat is not distributed by UV rays but IR (infra red) ones.
I haven't stopped being amazed what else people realize they can improve. Actually, it's nothing new under the Sun as my neighbor practiced painting roof of his cottage with a sliver color many years ago, in order to prevent overheating the inside.
Power cost is the best invention motivation, indeed.

My worry about infrared-reflecting paint on walls is that it might make you uncomfortable and maybe tan your retinas. All that radiation being reflected. Roofs would be better, I guess.

Instead of reflecting sunlight, how about capturing it with a cultivated roof?

The whole point is not to capture sunlight on a green roof, or even to directly affect the heating or cooling of your house. The earth is warming because excess CO2 causes little bit of heating which leads to a bit more humidity, which traps a LOT more sunlight before it can be reflected back into space due to increases in cloud cover and the strong IR absorption of water vapor. BUT, if the earth is "whiter" it reflects more sunlight back into space, despite the presence of higher CO2 levels. Just like a car with a white interior stays cooler on a sunny day, than a car with a black interior.

This is the main reason scientists are concerned about the ice caps melting. It doesn't increase sea levels directly, but blue ocean water absorbs a lot more sunlight than white snow- leading to a runaway heating affect that can't be stopped.

see a related proposal called "EarthLight" at the Buckminster Fuller site- challenge.bfi.org/application_summary/34#

I have "white" shingles. My HOA does not allow a coated roof, but I would love one. The winds from thunderstorms rip the shingles up because the pitch is too low. I don't doubt that it would increase the reflection of IR heat to have a white coated roof.

I'm really glad the state and national policies are overriding the HOA rules. Telecommunications Act of 1996, solar panels, etc...

I've sometimes thought that we should have seasonal panels or something that change from white to black depending on whether it's too cold or hot. White shutters over a black roof works, but you have to keep the birds and debris out too. I had an idea about sliding solar panels on a huge trolly that moves back forth to cover and uncover the roof. The cost of the trolly would probably be nearly the same as the PV panels unless it was made in volume (difficult with many different floor plans).

This is a huge trend in Hawaii, where I live. All condos that have their roofs redone have them done in white.

"Hmm Iin places where it snows lighter roofs will help in the summer but in the winter wouldnt it also stop then sun from helping to heat your home ?"

It would depend on the number of degree heating days and degree cooling days in your area.

Some places are 9 months of winter and three months of poor sledding, and others are 3 months of hell and 8 months of nice weather, and 1 month of cold.

:)

The whole point is not to capture sunlight on a green roof, or even to directly affect the heating or cooling of your house. The earth is warming because excess CO2 causes little bit of heating which leads to a bit more humidity, which traps a LOT more sunlight before it can be reflected back into space due to increases in cloud cover and the strong IR absorption of water vapor. BUT, if the earth is "whiter" it reflects more sunlight back into space, even in the presence of higher CO2 levels. Just like a car with a white interior stays cooler on a sunny day, than a car with a black interior.

This is the main reason scientists are concerned about the ice caps melting. It doesn't increase sea levels directly, but blue ocean water absorbs a lot more sunlight than white snow- leading to a runaway affect that can't be stopped.

see a related proposal called "EarthLight" at the Buckminster Fuller site- challenge.bfi.org/application_summary/34#

"Hmm Iin places where it snows lighter roofs will help in the summer but in the winter wouldnt it also stop then sun from helping to heat your home ?"

In snowy climates, you want the snow to build up on your roof (they're USUALLY built to withstand the weight) because it acts as additional insulation. If a roof has bare spots on it in the middle of winter it is often an indication of poor attic insulation and heat escaping from the house.

This is a really good idea. Many who are in a sunny area but can't afford solar panels just yet, may find white or pastel colored paints a really cheap method.

I watched the E! True Hollywood Story about Christie Brinkley a few years ago. She is an advocate for environmental conservation and this was her idea - to make all roofs (rooves?) white to reflect the sun!

This is an ages old idea that spans back centuries. Look at ancient buildings in England, Japan, and Africa.

However, this is something that has been happening (without a lot of attention) across the US for years (and elsewhere in the world for as long or longer, I am sure). It will not create "green jobs" as the same companies already producing roofing are producing the same products in different colors. The market is in place, the manufacturers are established, and they are already staffed. So while this is a great idea, we need to remember that not everything mentioned that is "green" and seems new will suddenly create this wealth of new "green jobs" (I'm getting a bit sick of this catchphrase being overused in situations where it blatantly doesn't apply - can you tell?)

If you want more info on cool roofing, how it works, and what products are out there right now for you to use on any building you own or design, check out coolroofs.org - it's been a great resource for years!

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Great Tip Heather! Totally understand about established industries, my point was only to say that if California, a HUGE state, suddenly mandates that all new residential and commercial buildings (and remodels) have to have lighter roofs, then there will be a need for staff to do this. Might create a few jobs. Or at least companies that are already doing this will get a boost in work. (hopefully!)

I found it hilarious that I mentioned this idea about 5 years ago to several people and they all thought something along the lines of "wha