Bill Bradbury wrote:
We used 5" and 6" fantech fans with cloth bags on the inlets and short duct runs into ceiling diffusers. Make sure to have a spring damper inline so air won't go out of the house into the attic.
From the way you talk it sounds like you're an HVAC pro?
Does the spring damper resolve any fire blocking issues?
How does the cloth bag work if it's on the inlet side? I've seen them on the output side of fans to act as dust collection bags. On the inlet is the bag just covering the 5" opening of the fan or do you have it stretched around a wire contraption to give it more surface area?