Home Garden

How to Block Lower Vents on a Gas Fireplace

When you are not using your gas fireplace, drafts come through the lower vents. This results in warm air escaping during the winter and cool air escaping in the summer. The vents on the gas fireplace should never be blocked when the fireplace is in operation. However, when the fireplace is cool and you are not using it for a period of time, it is possible to block the lower vents and stop the drafts. Although there are commercial products available, blocking the lower vents only requires a magnetic strip to cover the vent slots.

Things You'll Need

  • Tape measure
  • Magnetic sheets
  • Scissors
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Instructions

    • 1

      Check for a small handle on either side of the lower vents. Many gas fireplaces have a cover that slides over the vent holes similar to the lower vent holes on a charcoal grill. The handles are the same color as the lower part of the fireplace. If there are handles present, simply slide them to the opposite end of the vent. This closes the vent when the fireplace is not in use.

    • 2

      Measure the length and height of each lower vent. Some gas fireplaces have two while others have three vents. Add 2 inches to the overall length and height.

    • 3

      Cut a section of 1/4-inch-thick magnetic sheet to the size of each vent with a pair of scissors. Magnetic sheets are available at office supply stores and home improvement centers.

    • 4

      Place the magnetic sheets over the gas fireplace vents. The magnetic sheets will adhere to the metal of each vent.