Good evening:
First, based on your profile info, I have no idea of your qualifications, or backround.
Whole house fans can have motors that range from 1/2 to 5 HP. "Attic fans' usually are under 9 amps each, and yes a dedicated circuit may be required. Control can be a t'stat, timeclock, humidistat, switch, or any combo.
Depending where you are, working in a multi family may require a lic. electrical contractor; and a permit probably is also required.
More info on what you intend to do would be helpful
John
