Weatherize for Comfort & Savings

Upgrade & Optimize Your Home

Weatherizing your home is one of the easiest and most cost-effective ways to cut energy bills. With minimal up-front costs, weatherization and insulation should be one of your first energy-efficiency upgrades.

Through the Cracks: Enhancing Efficiency

Weatherizing includes caulking gaps and adding weather stripping to openings like doors and windows. Inspect your home and check all joints where different materials come together, for example between walls and a door or window frame, areas around electrical outlets, holes for plumbing, and walls and floor seams. Also check for less-prominent gaps around bathtubs and shower stalls, recessed cabinets, and attic hatches.

Detective Work: Locating Leaks

Hire a professional to perform an energy audit and blower door test on your home. This typically can cost anywhere between $200 and $500, depending on whether you choose only the blower door test, and the extent of the audit. You can also check yourself to get a general idea of where air leaks occur:

1) On a cool, windy day, turn off your furnace, shut all windows and doors, and turn on all exhaust fans, bathroom fans, and stove vents. Hold a lit incense stick or piece of lightweight string near seams in your home, around doors, windows, and vents. Use chalk to mark where the smoke or string moves.

2) To detect large leaks, work with a partner at night. Shine a flashlight through all seams with potential gaps, with one person inside and the other at the same point outside, where possible. A beam of light will reveal air leaks.

3) Shut doors and windows on sheets of paper. If you can pull the paper out without tearing it, weather stripping should be added.

Tool School

Caulk: Use caulk to fill gaps less than one-quarter inch between two immovable parts. 

Weather stripping: There are several different types for various kinds of windows and doorways to prevent leaks, without inhibiting functionality. Replace worn-out door thresholds, or use door bottoms or sweeps for doors without existing sills. 

Foam: Use expandable foam sealant to fill larger gaps that are not exposed to moisture or the elements. Backer rod or crack filler is a foam coil sold in ¼-inch to 1-inch dimensions. Use it to fill deep cracks and then finish with caulk.

Use & Care

Properly using and maintaining your home’s weatherization will maximize efficiency measures. Learn more about Weatherization Use & Care, where to start and how to keep your home sealed for savings. Return to Building and Materials.

This program is funded by California utility customers and administered by Southern California Edison under the auspices of the California Public Utilities Commission.