Steve B wrote:

Anyone know how much of a temperature reduction I'd get by
painting the shingles white, vs suspending a white tarp a
few inches over them?

What about painting them with a more expensive but much more
durable coating -- I'm thinking aircraft-type aluminum paint.

It looks like this sprinkler sprayer concept is leading so far.

Insulating Roof Coating Insul Cool-Coat #2000

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See also:

http://infinitipaints.com/products/roof-coatings

http://www.gardner-gibson.com/elasto...f_coating.aspx

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http://www.garagejournal.com/forum/a...p/t-74794.html

09-08-2010, 02:43 PM
Holy crap, Batman! I coated my dark shingled shop over the weekend, and
got an honest 40 degree drop in temps inside! Put it on right over the
shingles, some guys said OK, some said not to. It's as cool in there as
my carport is in the shade. No more 130 degree sweatbox, and I can store
my paints in there now.
I bought the good 12 year stuff, we'll see how long it lasts.
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http://www.finishing.com/116/34.shtml

You can paint asphalt roof shingles with any acrylic (water-based)
paint. I tested part of my roof and it's holding up fine. You need to
water it down a bit so that it covers the texture more easily without
brushing over and over. I'm about to paint my entire roof using 5 shades
of green, and painting each individual shingle. Don't know how long this
will take, but my stone cottage needs a jewel-like roof to crown it
properly. The part I tested is on top of a sun porch, which I painted
gloss white so the summer sun will reflect off of it. I've painted a
whole lotta things in my life, and I've come to the conclusion that
people worry too much... just go ahead and paint. I've even painted some
of the corner stones on my cottage with flat "terra cotta" colored
paint, and it looks like that's what they are made of. Life is short...
just do it.
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