How to Insulate a Dryer Vent

Most dryer vents run as uninsulated pipes from your dryer to the outside vent hood. They run exposed in your basement or another room, and the temperature differential between the room and the inside of the pipe isn't that drastic. However, if your dryer vent pipe runs into an unconditioned space like an attic or a crawl space, the temperature differential could be larger, causing condensation to form on the outside of the pipe. This may lead to mold or mildew. To prevent condensation, insulate a dryer vent that runs in an unconditioned space.

Things You'll Need

• Tape measure
• Duct insulation
• Utility knife
• 3-inch foil aluminum tape

Instructions

1. Calculate the circumference of your dryer vent pipe. Multiply the diameter of your dryer vent (usually 4 inches) by pi (3.14).

2. Add 4 to 6 inches to the circumference to allow for insulation thickness and enough overlap to secure the insulation to the pipe.

3. Cut a piece of duct insulation to the measurement, using a tape measure and a utility knife.

4. Wrap the insulation around the dryer vent and pull tight. It should overlap by an inch or two. Tape the insulation along the entire overlap seam with 3-inch foil aluminum tape.

5. Cut another piece of insulation and secure it to the dryer vent. Keep doing this until the entire length of dryer vent is wrapped with duct insulation. Tape all seams and connections with the foil tape.

Tips & Warnings

• Wear a dust mask and safety glasses when handling the insulation.

References

• U.S. Department of Energy: Duct Insulation
• Timothy Gonyo; Sheet Metal Workers Local 18; Milwaukee, Wisconsin