Top 5 Places & Top 25 Ways to Weatherize Your Home

Excerpted from the Solar Living Sourcebook by John Schaeffer. See the book for a helpful cutaway illustration pointing out 42 places to weatherize that are discussed in this weatherization article.
Short of printing your own money, weatherization and insulation are the best bets for putting cash in your wallet — and they’re a lot safer in the long run than counterfeiting. Weatherization, the plugging and sealing of air leaks, can save you 25 to 40 percent on your heating and cooling bills.

The average unweatherized house in the United States leaks air at a rate equivalent to a four-foot-square hole in the wall. Weatherization is the first place for the average home owner to concentrate for the most benefit with the least effort and expense. You’ll save money and help the planet!

The following suggestions are adapted with permission from Homemade Money by Richard Heede and the Rocky Mountain Institute.

1. In the attic

  • Weatherstrip and insulate the attic access door.
  • Seal around the outside of the chimney with metal flashing and high-temperature sealant such as flue caulk or muffler cement.
  • Seal around plumbing vents, both in the attic floor and in the roof. Check roof flashings (where the plumbing vent pipes pass through the roof) for signs of water leakage while you’re peering at the underside of the roof.
  • Seal the top of interior walls in pre-1950s houses anywhere you can peer down into the wall cavity. Use strips of rigid insulation, and seal the edges with silicone caulk.
  • Stuff fiberglass insulation around electrical wire penetrations at the top of interior walls and where wires enter ceiling fixtures. (But not around recessed light fixtures unless the fixtures are rated IC [for insulation contact]). Fluorescent fixtures usually are safe to insulate around; they don’t produce a lot of waste heat. Incandescent fixtures should be upgraded to compact fluorescent bulbs).
  • Staple Radiant Barrier under the rafters or joists to reflect 97 percent of the radiant heat that strikes it
  • Seal all other holes between the heated space and the attic.

2. In the basement or crawlspace

  • Seal and insulate around any accessible heating or A/C ducts. This applies to both the basement and attic.
  • Seal any holes that allow air to rise from the basement or crawlspace directly into the living space above. Check around plumbing, chimney, and electrical penetrations.
  • Caulk around basement window frames.
  • Seal holes in the foundation wall as well as gaps between the concrete foundation and the wood structure (at the sill plate and rim joist). Use caulk or foam sealant.

3. Around windows and doors

  • Replace broken glass and reputty loose panes.
  • Install new sash locks, or adjust existing ones on double-hung and slider windows.
  • Caulk on the inside around window and door trim, sealing where the frame meets the wall and all other window woodwork joints.
  • Weatherstrip exterior doors, including those to garages and porches.
  • For windows that will be opened, use weatherstripping or temporary flexible rope caulk.

4. In living areas

  • Install foam-rubber gaskets behind electrical outlet and switch trim plates on exterior walls.
  • Use paintable or colored caulk around bath and kitchen cabinets on exterior walls.
  • Caulk any cracks where the floor meets exterior walls. Such cracks are often hidden behind the edge of the carpet.
  • Got a fireplace? If you don’t use it, plug the flue with an inflatable plug, or install a rigid insulation plug. If you do use it, make sure the damper closes tightly when a fire isn’t burning.

5. Around the exterior

  • Caulk around all penetrations where electrical, telephone, cable, gas, dryer vents, and water lines enter the house. You may want to stuff some fiberglass insulation in the larger gaps first.
  • Caulk around all sides of window and door frames to keep out the rain and reduce air infiltration.
  • Check your dryer exhaust vent hood. If it’s missing the flapper, or it doesn’t close by itself, replace it with a tight-fitting model.
  • Remove window air conditioners in winter; or at least cover them tightly, and make rigid insulation covers for the flimsy side panels.
  • Caulk cracks in overhangs of cantilevered bays and chimney chases.