White Roofs

Secretary Steven Chu discusses the benefits of switching to white roofs and light colored pavements.

• Category

  Science & Technology

[kaevne]

I agree, Steven Chu I admired you as an Asian-American in the Cabinet, but this kind of blatant discrimination against colored-roofs is appalling.

[Ares550]

White roofs are great, they really should be implemented wherever possible.

White surfaces would control the "heat island" effect in large cities, which cause

higher energy usage, pollution, and poorer water quality (eutrophication).

HOWEVER

There is a disadvantage to white roofs. They are commonly made with PVC, which can become brittle and fail over time. in areas of large temperature variations or where there is snow, it may not be worth the while to use these surfaces.

[Patrick Grieshammer]

Cont'd... foam. Many different things that have different expansion and contraction figures. This is called thermal shock and it is the cause of cracks, splits, tears, and many other damages that make your roof fail and leak. You can make your roof last twice as long by cutting down on the thermal shock. You can also redo this every 5, 10, 15 years as needed to make your roof last indefinately. This is called sustainable roofing.

[Patrick Grieshammer]

By reflecting between 80 and 95% of the UV rays from the sun. Reflectivity and emmisivity work hand in hand to protect year round. But the real savings in colder climates is to the roof itself. A black roof will change temp from night and day nearly 100 degrees, regardless of the season. Black roof summer daylight 180, night 80. Winter daylight 100, night 0. That's a 100 degree swing each day which expands and contracts your entire roof, which made up of metal, asphalt, rubber, brick, concrete,

[Patrick Grieshammer]

There are many white coatings for virtually any type of roof. They are extremely reflective, up to 95% reflectivity, easy to apply and economical versus putting on a membane such as PVC. They are also sustainable, which means you can recoat in 10 or 15 years to keep the roof white and cool.

[Patrick Grieshammer]

PVC is a small piece of the white roofing market. TPO, which is flexible unlike the PVC materials, White EPDM, which is rubber and extremely flexible, white granulated asphalt rolls, as well as white coatings that can go over any roof surface.

[Patrick Grieshammer]

It's already happening in the state of California, by law, Title 24, and has been adopted in many other states and municipalites including New York city.

[Gainesvilleroofing]

This seems to be just a bunch of hoo ha and has no practical application as you can't possibly get enough cooperation to make this happen. Unless we pass another law mandating yet another thing that impinges on our freedoms.

[carehire99]

pretty clever stuff.

[ehmfrancisco]

Finding ways and introducing it to the public to help conserve energy reflects the dedication of Steven Chu to his work.

[shandcunt]

@Ares550 "They are commonly made with PVC" - Why does a different colour mean different building materials. Im no genuis but what about.....paint?

Why couldnt you jst paint your roof tiles / shingles / whatever

[Jeff Berlat]

All the street on Freeways are already white.