I have a whole house fan and I find it extremely effective. Depending on the outside temperature, it can cool far faster than the a/c, equalizing the outside and inside temperatures in a matter of minutes. There are deadspots in my house, especially upstairs, that the a/c will not reach so the fan is critical. On full blast, it sounds like a squadron of helicopers dusting off at the same time. However, it has a dimmer type control for infinite speed control and it is very quiet on low speed. The main drawback is you can only use the fan when the outside condition permits it because the fan basically exchanges the air inside of your house with the air outside: it must be cooler outside than inside, it must not be dusty or smoggy outside, etc. Also, if you have allergies, the fan will pull all the pollen outside into your house. I inadvertently had the fan on for a few minutes when my neighbors were having a bbq and my house smelled like smoked kalbi all night. I could not use it for a couple of weeks during and after the wildfires last November because the air was so bad.