Challenge: Stop Air Leaks, Caulk & Weatherstrip Your Home

You may not have noticed, but there are cracks all over your home that are leaking air...and heat.

This weekend, gather the family and search out the air leaks in your home, following our tips below, then take an hour or two to seal out the drafts. The time and relatively minor effort will be well spent: Caulking and weatherstripping an electrically heated home can save 1,000 lbs of CO2 and can reduce your home's heating (and cooling) bills by up to 40%.

What You Should Know

• If just one-fourth of the households in America weather-stripped and caulked their windows and doors this weekend, the reduction in heating and cooling costs would prevent eight million tons of carbon dioxide from being emitted this year - and every year after.

• Contrary to popular belief, insulation does not block the flow of air, only the flow of heat.

• If you add up all the tiny air leaks in an average home, not including leaks from ducts, they're equivalent to leaving a three-foot-square window wide open!

Easy Things You Can Do

Find the leak:

• Some evening, when your house is at least 20° warmer than outdoors, hold your hand up to various places around window and door frames. If you feel any drafts, the windows and door frames need weatherstripping.
  
• You can also use a smoking incense stick to look for drafts. Hold the stick near the places you think might have cracks, if the smoke dances, you've found a place to seal.
  
• Beyond doors and windowpanes, go to the following seven places to check for leaks:
  
  • Wherever a wall meets a floor, ceiling, doorframe, or another wall
    
  • Around the edges of light switches, electrical outlets, and light fixtures
    
  • Around fireplace flues, dryer vents, and range hood vents
    
  • Wherever pipes go thorugh walls or ceilings: check behind the washing machine, underneath the sink, behind the shower and toilet, et cetera
    
  • On the outside of your house: between the sliding panels, where the chimney and siding meet, where the foundation meets the house, where the cable lines go into the house, et cetera
    
  • Around all window and exterior doors (including sky lights and storm windows)--if you can rattle them or see light shining in around them, air is leaking through
    
  • In your attic--this is the most common place to find air leaks--around your attic door or pull-down stairs, around any wiring, piping, or ductwork that enters the attic through your ceilings or walls, and where your chimney goes into the attic. A dirt streak on your attic insulatin means there's an air leak underneath (where dusty air has been escaping and creating a stain).

Tackle the Big Leaks take more effort to seal and should be done first. To fix a big leak in your attic, staple a plastic sheet over it and caulk around the edges of the sheet. You can also greatly reduce air leakage in your attic by having a contractor blow high-density cellulose insulation into large or hard-to-reach spaces.

Use Caulk for leaks that are less than a half-inch wide, to seal around almost everything: doors, windows, soffits, medicine cabinets, heating registers, light switches, and electrical outlets; pipes or cable wires that go through walls; where walls, floor, and ceilings meet; and any leaks to the outside. Be sure to choose the approppriate type of caulk for your needs (exterior, interior, windows, et cetera).

Use Foam Sealant or foam caulking to seal gaps that are more than a half-inch wide. There are three main types: expanding, nonexpanding, and sprayed in. use the type most appropriate for the job and don't use on doors and windows.

Use Weather Stripping around the edges of exterior doors, attic doors and hatches and windows in order to make them air tight. Pay close attention to the thresholds of your doors--if weather stripping is not enough to plug the leak, attach a door shoe (a plastic flap that sweeps along your floor), or make a cloth "snake," fill it with sand or beans, and lay it against the bottom of the door to keep the wind out.

Use Window Putty (also called glazing compound) to hold loose windowpanes in place and seal them.

Special Considerations: When sealing around your fireplace flue, chimney, kitchen exhaust fan, or dryer vent, be sure to use heat-resistant, noncombustible caulk or foam. Second, make sure all electrical outlets (even the ones in your basement) have covers on them, and install rubber gaskets behind all outlets and switches to prevent air leakage. Last if you have lighting fixtures that are recessed into the ceilling, make sure that they are airtight "Insulted Ceiling" (IC) fixtures, and then seal around them with heat-resistant caulk.


Sources: 30 Simple Energy Things You Can Do To Save The Earth, by PG&E, 51 Easy Ways You Can Prevent Global Warming and Save Money by Jeffrey Langholz, PhD, and Kelly Turner.