Painting the town WHITE

[Martin Cassini]

Obama's climate change minister, Nobel-prize winning scientist, Steven Chu, is promoting an idea which is elegant in its simplicity (and akin to FiT philosophy). Paint roofs white! Buy white cars. Use pale colours for tarmac, car parks and pavements. Why? To reflect sunlight back into space. Dark materials retain heat and cause infrared radiation, adding to global warming. In winter, white roofs reflect escaping heat back into buildings. The dramatic energy savings are similar to those we'd get from letting traffic filter instead of making it queue at gas-guzzling traffic lights. Article here.

[phunksta]

UK Flat roofs are generally coated in a white limestone chipping, with Green mineral bonded felt.
Pitched roofs are a majority of red clay tile. Slate is the other material - unfortunately black ;)
We also generally have a high degree of roof insulation to protect against our less than clement climate.

I would say that this advice has a keen US bias, where domestic aircon is prevalent.

I've got to agree with Prince Charles on this one: Stop de-forestation first, before tinkering.

[Martin Cassini]

White roofs are supposed to counter the heat island effect too, but yes, I've always seen the sense and supported the idea of green roofs, sedum roofs, roof gardens, etc. There is never going to be a single solution.

[Ian Perry]

Whilst a white roof may keep a building cooler, many buildings do not use energy to cool them, but to heat them. A green or brown roof averts the “urban heat island” effect, is better for the environment and provides good insulation to keep the interiors of buildings at appropriate temperatures. Birds, and other wildlife, enjoy green roofs. Would wildlife enjoy the glare of the sun reflecting from a white roof?
The redevelopment for the Millennium of the area of central Bristol, known as The Centre, included resurfacing the area with light grey paving. Yes, the light coloured surface does reflect the sun, but pedestrians are unable to see due to the glare!