How to Winterize an Attic Fan
- 1). Measure the fan opening in the ceiling. This is the louvered opening where air enters and exits the attic.
- 2). Cut a sheet of plastic 1 inch larger than the fan opening on all sides. Tape this plastic over the fan opening, sealing it with tape all the way around the opening.
- 3). Climb into the attic. Locate the safety switch beside the fan and turn it off.
- 4). Cut the insulation bats to fit inside the fan housing. Wearing gloves, stuff the insulation into the fan housing until it's full. Iowa State University notes this is the least expensive method of insulating a fan.
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