The 2nd floor -- containing our 3 bedrooms -- IS my attic in my circa 1824 Bayman's Cottage. During the day the first floor is cooled by 1 window AC that does a decent job... but the 2nd floor heats up unbearably to over 100 degrees. If I do a whole house fan, I'm afraid it will suck unhealthy, moldy-cistern/basement air into my living space. So I was thinking of just trying to clear the hot air on the second floor... But what's most efficient? Do I put a separate wall venting attic fan high up on the outside wall in each of the 3 rooms? OR can I put one in-between-the-rafters fan in my ceiling crawlspace to vent out the back wall of my house attached to ducts running through the ceiling crawl space to each of the 3 bedrooms to gently and quietly suck out the hot air?