While there are many different types and styles of these fans available in the marketplace, if you are looking to purchase a whole house fan – consider investing in a system that is whisper quiet, easy to install and requires no maintenance. The fan is stationary and is typically attached to ceiling joists or a frame built to support the fan and its motor. The fan works great if we prop the louvers open. Make sure there is at least 30 inches of clearance above the blades of the fan, or air will be forced back through the shutter. Whole house fans pull the air into your house and through any available open windows. Louvers open when the fan is running and close to seal the hole when it is not. Re: Whole house fan - possible to add variable speed? They also rattle a bit. As far as performance, I notice the fan's louvers (in the living space) open about halfway when the fan is on. ... it won't >> open the louvers I think, which are just sucked open. It moves cool air in and moves hot air out at the same time. fuse (or worse?). More air helps the shutters open all the way. There are also insulated caps that can be slipped over the louvers for added insulation in the winter. We do not know when the fan was installed or who made it - however, it is a very large whole house fan - 42" blades with 46" frame. When we measure the shutter cover in place now we get odd measurements. In order to achieve cooling in these hot, humid climates (imagine a night that stays hot and sticky all night long) the air must move fast enough to create evaporative cooling on the skin (like a fan blowing right on you on a hot day). Do not put the fan in the bedroom. Whole house fans may also be installed in walls or on rooftops for homes without an attic. There is a belt-driven whole house fan in the attic that we would like to get working again. This type of fan is installed in the ceiling, and louvers open when the fan is turned on. Whole-house fans usually have automatic louvers. So that tells me the #'s are about right and that I need at least 7-8sf of add'l vent space. Open windows if the shutter rattles. However, it is also a superior, powerful air circulation method. It makes too much noise and you won't be able to sleep. The louvers on the whole house fan won't stay open. We have recently purchased an older home, built in 1931. Traditional whole house fans were popular in the 1950s, before A/C was common, mostly in the South and Midwest. Usually the heavier the fan and louvers, the less of a problem this will be. Most whole house fans tend to be 24 or 30 inches. I installed one of these fans in a house near Chicago, and frankly, the overall insulation of the house was poor enough that there would be no point to insulate just one 2x2 foot bit of the ceiling. Re: Whole house fan - possible to add variable speed? The fan is as far as possible from the bedrooms. Newer whole-house fans are available that have a flow range between 1,000 and 3,000 cfm. Now the problem is we don't know how to accurately measure. Using a whole house fan is a cost effective and efficient way to cool your home. The motor is not the problem. The traditional whole-house fan is fairly large and noisier than small fans, but can move between 4,000 and 7,000 cfm of air. Like a box unit or a ceiling fan, a whole house fan cools down your house. Access panel opening is ~7.5sf. They then push it out through your attic forcefully. I have a 36" whole house fan in the eave with a screened louver in front of the fan and a draft operated register in the ceiling in the center of the house. Also if a whole house fan gets too slow, it won't open the louvers I think, which are just sucked open. We were told to replace the shutter. If I open the attic access panel, the louvers open fully and its noticeably quieter.