clinehall wrote:
my sister just did that deal with the reflective insulation in the attic in Wilmington. I am anxious to see here results. I think that could be done in a couple of saturdays with out any problem
When we built the house we're in now back in 2002, we used plywood boards with reflective radiant shielding for the roof. These had just come on the market at the time. It is essentially a typical plywood panel with an aluminum foil like surface that faces the inside of the attic which significantly reduces the thermal radiation from the inside attic roof into the attic itself.
The emissivity of the aluminum panel side is something less than 0.1 while that of typical plywood is in the range of 0.8 to 0.9. Hence it clearly will reduce radiation heat transfer off the attic roof substantially. It works the other way of course too in the winter although the temperature difference is likely lower compared to the delta T in the summer. Since it was here from day one, I can't really give any improvement thoughts other than the attic isn't nearly as hot in the summer. There must be some on-line data for this stuff, but I've not searched.
As an aside, we also used blown cellulose insulation in all the walls and attic which has worked out superbly. The walls are much warmer in the winter resulting in it "feeling" warmer in the house (less radiation from your body to the wall that it can "see"), so we're able to comfortably have the thermostat lower than would be typical I guess. A side benefit is that the house is much quieter than a fiberglass insulated one. We also used it in the interior walls of all the bathrooms and my office to suppress noise.
So far I'm very pleased with the energy consumption of the house some 7 years on now.
By the way, I swear there was a thread not too long ago on the board here about geothermal heat pumps.
