Right on... Thats a hell of a lot of CFM to be sucked out of that building, no exhaust issue I would think.... If I may make a suggestion, wire the fan 460 volts. It will be cheaper to run, because it will pull less amps. If your wondering who I am, I do start, test and air balance for the largest mechanical contractor in SD. I've been a sheetmetal foreman for years as well. If I can help you in anyway, please let me know.......