20 Inch Box Fan Air Filter

With all the wild fires and smoke this year I wanted an air filter for the house and I did not want to buy an expensive device that uses even more expensive filters. I designed these clips for my inexpensive 20 inch Lasko box fan. The clips will hold any 20" x 20" x 1" furnace filter. I used a reusable and washable filter I found at Lowes but any 20x20x1 filter will fit.

I designed two sizes of clips. The large clips do hold quite well and would make for a strong permanent installation. The small clips tend to sag and slide a bit, but do work just fine. The small clips are easier to install as they are more flexible.

If I had a garage I would use this while woodworking to keep the air clean.