Chapter

Air Leaks and Energy Loss

Sealing Air Leaks

Warm air leaking into your home during the summer and out of your home during the winter can waste a lot of your energy dollars. One of the quickest dollar-saving tasks you can perform is caulk, seal and weatherstrip all seams, cracks and openings to the outside. You can save on your heating and cooling bills by reducing these air leaks in your home.

How Does Air Escape?

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Sources of Air Leaks in Your Home

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Areas that leak air into and out of your home cost you lots of money. Check the areas listed below:

  • dropped ceilings;
  • recessed light fixtures;
  • attic entrance;
  • sill plates;
  • water and furnace flues;
  • all ducts;
  • door frames;
  • chimney flashing;
  • window frames;
  • electrical outlets and switche plates; and
  • plumbing and utility accesses;

Tips for Finding and Sealing Air Leaks

Air infiltrates into and out of your home through every hole and crack. About one-third of this air infiltrates through openings in your ceilings, walls and floors. Here are some measures you can take yourself.

  • First, test your home for air-tightness. On a windy day, carefully hold a lit incense stick or a smoke pen next to your windows, doors, electrical boxes, plumbing fixtures, electrical outlets, ceiling fixtures, attic hatches, and other locations where there is a possible air path to the outside. If the smoke stream travels horizontally, you have located an air leak that may need caulking, sealing or weatherstripping.
  • Caulk and weatherstrip doors and windows that leak air.
  • Caulk and seal air leaks where plumbing, ducting or electrical wiring penetrates through walls, floors, ceilings, and soffits located over cabinets.
  • Install foam gaskets behind outlet and switch plates on walls.
  • Look for dirty spots in your insulation, which often indicate holes where air leaks into and out of your house. You can seal the holes with low-expansion spray foam made for this purpose.
  • Look for dirty spots on your ceiling paint and carpet, which may indicate air leaks at interior wall-ceiling joints and wall-floor joints. These joints can be caulked.
  • Install storm windows over single-pane windows, or replace them with more efficient windows, such as double-pane.
  • When the fireplace is not in use, keep the flue damper tightly closed. A chimney is designed specifically for smoke to escape, so until you close it, warm air escapes—24 hours a day!
  • For new construction, reduce exterior wall leaks by installing housewrap, taping the joints of exterior sheathing, and caulking and sealing all the exterior walls.
  • Use foam sealant for larger gaps around windows, baseboards, and other places where warm air may be leaking out.
  • Kitchen exhaust fan covers can keep air from leaking in when the exhaust fan is not in use. The covers typically attach via magnets for ease of replacement.
  • Replacing existing door bottoms and thresholds with ones that have pliable sealing gaskets is a great way to prevent conditioned air from leaking out underneath exterior doors.
  • Fireplace flues are made from metal and, over time, repeated heating and cooling can cause the metal to warp or break, creating a channel for hot or cold air loss. Inflatable chimney balloons are designed to fit beneath your fireplace flue during periods of non-use. They’re made from several layers of durable plastic and can be removed easily and reused hundreds of times. Should you forget to remove the balloon before making a fire, the balloon will automatically deflate within seconds of coming into contact with heat.