Weatherization near you

The three overlap, so it helps to know where each one stops. Weatherization is the seasonal, surface-level package: it deals with the moving parts and visible joints of the living space, uses low-cost materials and needs little more than a ladder, a utility knife and a caulking gun. Air sealing, covered on its own page, goes after the large hidden leaks at the attic floor, the tops of walls and the rim joist. Insulation adds resistance to heat flow through the attic, walls and basement.

Natural Resources Canada's Keeping the Heat In guide treats weatherstripping and caulking as part of its wider advice on controlling air leakage, so a weatherization visit is often the first step rather than the whole answer. If the drafts persist after the doors and windows are done, or you notice attic frost or ice dams, an EnerGuide evaluation will show whether bigger leaks or missing insulation are the real problem.

A contractor or program advisor usually starts with a walk-through, asking where the house feels cold and checking every exterior door and window, the outlets on outside walls, the attic hatch and any pipes in unheated spaces. The materials are then matched to each spot: different weatherstripping profiles for narrow and wide gaps, exterior-grade caulking outside and paintable caulking inside, an adjustable sweep or a replacement threshold at the door bottom.

Most of the work happens indoors and is finished in a day. Outdoor caulking needs mild, dry weather to cure properly, which is one reason early fall is the easiest time to book. Anything the visit turns up that falls outside weatherization, such as a window that won't close, a failing exterior door, suspect wiring behind a cold outlet or damp insulation in the attic, is noted for the right trade rather than patched over.

Several programs install weatherization measures at no charge for households that meet an income limit or receive certain benefits. The income thresholds are posted on each program's page and can change from one year to the next, so check the current criteria before applying. When this page was reviewed, these programs were running:

Every gap you close removes a little of the accidental ventilation an older house has always relied on. A few new sweeps and window kits rarely change much on their own, but combined with insulation and air sealing they can leave less air for a naturally vented furnace, water heater or wood fireplace, the combustion spillage risk Natural Resources Canada describes. Moisture that used to leak out stays in, too, so condensation on the new window film is a sign to run the exhaust fans more.