Join Date: Apr 2012
Location: Waynesfield, OH
I have no idea what the CFM of mine was, it was a recycled 4 speed blower from an industrial furnace (snatched it from work). But if you look at the commercial ambient air cleaners they move somewhere between 500 and 1200 CFM. A smaller room may get by with a smaller blower, after all it's the air changes that count. But I think I would try to cabbage a discarded furnace blower from an HVAC installer...you might get it free. For construction, there have been several plans published, my favorite one was in Wood and had the blower/intake on one end of the shop and the exhaust ducted to the opposite side. That was a little too complicated for me, I built a plywood wood box, put the blower more or less in the middle of it, and a cheap fiberglass filter to cover the exhaust. But for filtering I put 3 furnace filters (20x25") at the inlet. Each was a progressively tighter filtration. Doing that made the most expensive one (Filtrete Ultra-Allergen) to last longer. The first one had to be changed fairly often, the second a little more often,and so on. the second one was a Filtrete "red", and the first one was whatever cheap pleated filter I could find. This unit worked very well. Alas, I left it in my last shop when we moved.
"I long for the days when coke was a cola and a joint was a bad place to be" (Merle Haggard)