I started looking into Whole House Fans (hereafter WHFs) and as another option, but upon further research found that they needed to vented into an attic space, or outside the home. Because of our Mansard roof, and the floor plan of the second floor neither of these options was possible. We did, however, have a narrow door into the attic of the garage at the end of the hall. This was enough to set my plan in motion.
I did some research on WHFs and found information online regarding sizing the fan to the square footage of your house, pricing, *CFM (Cubic Feet per Minute), etc. I found that I needed "X" amount of CFM for my home and did some online shopping for WHFs.
STICKER SHOCK....WHFs are expensive. While digging around online I stumbled across Drum Fans. These fans are typically used for moving air around workshops, so they're pretty capable of producing gale force winds. I also found that, on average, the drum fans have a higher CFM rating than any WHF with the same blade diameter, and they were 1/3 to 1/4 the price. So I started shopping around for a suitable Drum Fan that I could convert into a WHF. I spec'd one online that moved 2,000 CFM more than a suitably sized WHF, but being "Mr Instant Gratification" I looked for one locally and luckily stumbled across local hardware store that was out of stock, but had a floor model that they'd be willing to sell for less - so I was now at 1/5 the price of a WHF.... BONUS!!!