Fan door clears shop air
Here's a simple way to rid your shop's air of fine particulates—the kind that stay suspended and prove most damaging to your lungs. Build the frame using 2×4s. Mount three 20" box fans and a power strip, then use the remaining frame space for storage cubbies. In nice weather, open the exterior door and use the fan door to exhaust particulates. Be sure to open another door or window to create a draft.
I have an outward-opening exterior door, so I simply attached the fan door to the existing door jamb with four heavy-duty hinges. Or, mount the fan door on sliding-door hardware, as shown. Another option: You could add outriggers and casters to the frame and simply roll it up to the open door when needed.
If your fan door swings open, or is mounted to outriggers, attach a furnace filter to each fan with bungee cords, and recirculate the air through the filters in cold weather.
—John Evans, Calgary, Alta.