Attic/ceiling fans

[csgray]

When I was growing up in the hot and humid mid west my parents put attic fans in every house they built for us. These were fans with timer switches that were set into the ceiling in an upstairs central location, and vented into the attic. These fans could replace all the hot air in the house with cool outside evening air in a matter of minutes.

Does anyone have actual experience using these here in Puna? We would be doing a retrofit in a house with a mostly cathedral ceilings except a small well vented attic over the bedrooms and baths. The living room gets full western sun every afternoon and I would love to be able to pull that hot air outside and replace it with cool air when the sun goes down.

Maholo,

Carol

[Carey]

Those attic fans sound like "Whole House Fans":
http://en.wikipedia.org/wiki/Whole-house_fan
Very common in the midwest, but I haven't seen then here, may have to custom order????

[Rob Tucker]

Now there's an energy savings idea... bigger fans. I wonder what is so intimidating about buying and installing roof insulation that paying a higher electric bill for decades actually sounds attractive. Does anyone remember that we have the highest electric rates in the country?

[oink]

I have two whole house fans in my house. Here in S. Fl they work best in the winter when you don't really need them because the humidity is low. In the summer when it's hot and humid they leave everything wet and cause crazy mold. Some air flow may help keep mold down in high humidity but a breeze does not. That said, they will cool the house down quickly at night by ridding the house and attic of hot air.

Having learned my lessons with them I now only use them to rid the house of unwanted odors like when cooking fish. If both fans are turned on full blast they will slam your doors shut and whistle the screens. When I build again I will put in one just for the air clearing properties.

I have plenty of soffit vents all the way around, gable vents and ridge vents. I have radiant barrier and thick fiberglass insulation. I also have plenty of attic space, I can stand up in a lot of it. It still gets unreal hot. I will run the whole house fans if I have to work in the attic just to cool it down more.

I have a friend who built in the last couple of years. He has no attic vents. His attic is sealed and is completely sprayed with thick foam on the inside. The house is the poured foam block construction similar to what Rob sells. The attic on this house is almost cool in the middle of the summer. He runs the AC all of the time but his summer power bill is like my winter power bill.

Pua`a
S. FL
Big Islander to be.