Paint My Roof
It wouldn't have much of an effect. Winters tend to lack a lot of sun and the sun during winter isn't "strong" enough to affect the indoor temperature. Most likely the sun rays going through the windows would do much more.
Yes! "Steven Chu, the U.S Secretary of Energy and a Noble Prize winning scientist, has said that painting roofs white or another light color would help to reduce global warming by reflecting sunlight back into space —it would be like removing every vehicle from the planet for 11 years."
Source Date: 28 December 09
"The Earth has an albedo of 0.29, meaning that it reflects 29 % of the sunlight that falls upon it. With an albedo of 0.1, towns absorb more sunlight than the global average...
Painting all roofs white could nudge the Earth's albedo from 0.29 towards 0.30. According to a very simple "zero-dimensional" model of the Earth, this would lead to a drop in global temperature of up to 1 degree C, almost exactly canceling out the global warming that has taken place since the start of the industrial revolution."
Source Date: 28 December 09
Yes! Since most flat rooftops are coated with tar and gravel, painting over tar will be a very common thing to do. All that is required to properly paint over tar is a primer with an asphalt base. After the primer has been set any other paint can be painted over it.
It cleans the air through its titanium dioxide content.
"Better known as a pigment for whiteness, titanium dioxide can clear the air because it is an efficient photocatalyst: it speeds the breakdown of water vapor by ultraviolet light. The results of this reaction are hydroxyl radicals, which attack both inorganic and organic compounds, and turn them into molecules that can be harmlessly washed away with the next rainfall."
Source Date: February 02
