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Heating Weatherizing

One of the quickest dollar-saving tasks you can do is caulk, seal, and weather strip all seams, cracks, and openings to the outside. You can save 10% or more on an energy bill by reducing the air leaks in a building. According to the World Watch Institute, as much energy leaks through windows in the U.S. annually as moves through the Trans-Alaska pipeline every year.

Where do I start?

The following areas are common sources of air leaks:

  •     Dropped ceiling,
  •     Recessed light,
  •     Attic entrance,
  •     Electric wires and box,
  •     Plumbing utilities and access panel,
  •     Water and furnace flues,
  •     All ducts,
  •     Door and window sashes and frames,
  •     Chimney penetration,
  •     Warm air register,
  •     Baseboards, coves, and interior trim,
  •     Electrical outlets and switches,
  •     Light fixtures, and
  •     Sill plates.

First, test a building for air tightness. On a windy day, hold a lit incense stick next to windows, doors, electrical boxes and outlets, plumbing fixtures, 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 weather stripping.

Weatherizing Tips

  • Install rubber gaskets behind outlet and switch plates on exterior walls.

  • Look for dirty spots in your insulation, which often indicate holes where air leaks into and out of the building. You can seal the holes by stapling sheets of plastic over the holes and caulking the edges of the plastic.

  • Install storm windows over single-pane windows or install double-pane windows. Storm windows as much as double the R-value of single-pane windows and they can help reduce drafts, water condensation, and frost formation. As a less costly and less permanent alternative, you can use a heavy-duty, clear plastic sheet on a frame or tape clear plastic film to the inside of window frames during cold winter months. Remember, the plastic must be sealed tightly to the frame to help reduce infiltration.

  • For new construction, reduce exterior wall leaks by either installing house wrap, taping the joints of exterior sheathing, or comprehensively caulking and sealing the exterior walls.


  • Cellulose Insulation Manufacturers Association (CIMA), (937) 222-2462,

  •  National Association of Home Builders (NAHB), (800) 368-5242,