Gable Attic Fans - Do they really lower Energy Bills?
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Gable Attic Fans - Do they really lower Energy Bills?
I have a house in Phoenix Arizona with a gable roof and louvres on opposite sides 50 ft apart.
Would an attic fan help reduce cooling bills by moving out the oppressively hot air in the attic during the summers? I was thinking of mounting one on the south side gable that has a built in thermostat.
Any opinions and thoughts would be appreciated, thanks.
Would an attic fan help reduce cooling bills by moving out the oppressively hot air in the attic during the summers? I was thinking of mounting one on the south side gable that has a built in thermostat.
Any opinions and thoughts would be appreciated, thanks.
#2
Try to size it to the square footage. When I installed one in my last house, I wasn't watching the bills so much as how much quicker my central air cooled and held the temp, even in the heat of day. Draw from the north and exhaust to the south.
#3
If your objective it so save money, gable fans will use energy, so the savings isn't there. You may want to consider ridge vents and soffit vents to compliment the gable fans. This will be a passive way to move the hot air from the attic. Of course, as Goldstar said, be sure to size the fan correctly if you do plan on moving in that direction.
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Thanks for the responses. I've researched some more and it looks like there will be no energy savings (despite the outrageous claims of many sellers). But to cool the house down faster seems like an intriguing benefit.
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Just my $.02 from doing some research (about ceiling fans) and what other posters have mentioned here.
Yes, the gable fan will use some energy. Just like a ceiling fan uses energy. With a ceiling fan, it allows you to raise your thermostat. So you save energy because your AC is on less and the ceiling fan uses a lot less energy than an AC unit.
A previous poster mentioned that his house seemed to cool down quicker. So your AC is running less. I would imagine (similar to a ceiling fan), that the gable fan uses less electricity than your AC unit. So if the house cools off quicker, the AC runs less, and that is how you save money.
Is it a lot of money you save? I honestly have no idea and I wouldn't believe the saleman. I always here claims of 30-40% of your heating bills or cooling bills, yada yada. But cooling or heating isn't all of the bill.
Maybe in combination with other items (radiant heat barrier stapled to the underside of the rafters, etc.), you could make a larger dent in your bills and be eco-friendly by cutting energy consumption.
Again, just throwing in my $.02 from my journeys around the web. Hope it helps. Worst case is you can return the fan at the end of the summer if it doesn't make a difference (if the store has a 90 day return policy or something similar). You got the louvers already, so install should be fairly easy I would think.
-Neil
Yes, the gable fan will use some energy. Just like a ceiling fan uses energy. With a ceiling fan, it allows you to raise your thermostat. So you save energy because your AC is on less and the ceiling fan uses a lot less energy than an AC unit.
A previous poster mentioned that his house seemed to cool down quicker. So your AC is running less. I would imagine (similar to a ceiling fan), that the gable fan uses less electricity than your AC unit. So if the house cools off quicker, the AC runs less, and that is how you save money.
Is it a lot of money you save? I honestly have no idea and I wouldn't believe the saleman. I always here claims of 30-40% of your heating bills or cooling bills, yada yada. But cooling or heating isn't all of the bill.
Maybe in combination with other items (radiant heat barrier stapled to the underside of the rafters, etc.), you could make a larger dent in your bills and be eco-friendly by cutting energy consumption.
Again, just throwing in my $.02 from my journeys around the web. Hope it helps. Worst case is you can return the fan at the end of the summer if it doesn't make a difference (if the store has a 90 day return policy or something similar). You got the louvers already, so install should be fairly easy I would think.
-Neil
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Have you given consideration to a solar-powered fan? They are a fairly high initial cost (relative to an electric fan), but over the long haul, cost you nothing in energy cost.
I have one installed (replaced a passive mushroop cap vent) & it seems to have improved my upper level temp in the summer.
Just food for thought.
I have one installed (replaced a passive mushroop cap vent) & it seems to have improved my upper level temp in the summer.
Just food for thought.
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I looked at Solar Attic fans and I don't think their cost and lack of efficiency vs. an electric powered fan make them viable. Seems more like a faddish idea. Plus I don't want to make a hole in my roof.
Of course, the other risks of attic fans is the negative pressure drawing in cold air from the house so I would need to consider caulking all the light fixtures.
Of course, the other risks of attic fans is the negative pressure drawing in cold air from the house so I would need to consider caulking all the light fixtures.
#8
If you have gable vents on each end and maybe a few soffit vents, you should not create a negative situation. Again, get a fan sized for your square footage. As to drawing small amount of air from the house, if heat still rises. you would pull the hot ceiling air blanket into the attic - Plus. Of course ambient outside air would then infiltrate the living quarters - Negative.