Gayle G
Gayle G
  • Hometalker
  • Raleigh, NC
Asked on Apr 26, 2012

What are the pros and cons of a whole house fan versus an attic fan? We are in a two story house, approx 1950 sq. ft.

WalterSusan SWoodbridge Environmental Tiptophouse.com
+8

Answered

In the warmer months the upstairs gets very warm so we are looking for a way to cool the upstairs.
10 answers
  • Debi M
    on Apr 27, 2012

    we installed an attic fan for that very reason. Our home is very similar to yours. The attic fan keeps the upstairs much cooler. We also have a tin roof on our home, so having the attic fan is a real asset in helping cool the upstairs.

  • 3po3
    on Apr 27, 2012

    A whole house fan is more expensive and a more complex install because it needs lots of gable and roof vents. However, it will cool your house more efficiently than an attic fan. On the other hand, as Debi said, an attic fan just pulls heat out of the attic, but that could be enough to cool the upstairs in your climate.

  • KMS Woodworks
    on Apr 27, 2012

    Sealing and Insulation are still some of the best ways to keep a house cool. R-38 in the attic is pretty much a "starting" point.

  • Gayle G
    on Apr 27, 2012

    Thanks for the answers, but I'm still hoping for more ideas. Thanks to each of you for your responses. One concern with the whole house is having the windows open. Not a good idea during pollen season. Some say open the windows, some say not necessary. It is all very interesting. Thank you.

  • Donna McCrummen
    on Apr 27, 2012

    If I mistakenly put my whole house fan on without a window open it sucks the oil smell in from the furnace. Open a window so the fan has air to suck in.

  • Douglas K
    on Apr 27, 2012

    The difference between the two are distinct. The attic fan is meant to bring in air from the soffits (the overhang of the roof) and pick-up the warm air or moist air and to exit that air out roof top vents. The whole house fan (direct drive or belt drive) is meant to bring in air from the whole house (open lower windows) and to push that air out attic vents, both soffit and roof top vents. The whole house style is the most efficient means of cooling off the upstairs of a house with outside air(hopefully cooler). The attic vent will get rid of the hot air in your attic, but you will need some sort of cooling to the upstairs to make that area livable. If the pollins in your area are a problem, I guess, it is a matter of how much does it bother you. Good luck.

  • Gayle G
    on Apr 27, 2012

    many thanks to all of you.

  • Just want to chime in on this a bit. Whole house fans called many times as poor mans air conditioning works well if properly installed and controlled. To many people install these types of fans on their ceilings without providing enough escape air out of the attic. The resulting condition oftentimes becomes mold. As these fans tend to work real well in the evening when the air outside begins to cool, it also begins to condense, which is why we see dew on the grass. Well this dew also collects in the attic along with all the mold spores that are carried in the air. Ideally the best location for this type of fan is on the gable end of the house, or in a attic dormer designed just to hold the fan. Then a vent of sorts is installed in the ceiling or wall leading into the area in which the fan is located. This allows the fan to draw the air out of the attic as well as pull it into the windows of the rooms throughout the rest of the home. The attic vent fan is just that. It pulls outside air into the attic lowering the attic temps so it makes it easier for the insulation to do its job. Currently the new methods of ventilation does not suggest a attic fan, in fact its frown upon as it uses energy not needed if the attic is properly vented both along the soffit and ridge of the home. As a home energy company, we try to foam the back side of the roof and seal off the entire soffit area with spray foam. We get over R-32, no issues with moisture and if HVAC equipment is located in the attic space it brings it into the building envelope which lowers its load requirements close to 25%, meaning you can get away with smaller more efficient equipment.

  • Susan S
    on Apr 30, 2012

    Chime #2. here: My home is the same sq. footage - 2 story colonial. Do you have ceiling fans as well? We use our in the MBR all year long - usually on low and just the simple air circulation makes a big difference too. My husband SWEARS that by closing some of the air vents downstairs forces more of the cool air upstairs. Can't really say I've noticed any difference but then I think it's a "guy thing"!! LOL

  • Walter
    on Dec 22, 2014

    Some of the newer style of whole house fans are extremely quiet and do not require any framing. We recently purchased a ducted whole house fan from Centric Air and hired an electrician to install it. It took him a couple of hours to install it and after he completed the job he said it was the easiest whole house fan he ever installed.

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