Short answer: walk through your home looking for air leaks, thin insulation, tired heating equipment, old lighting and always-on electronics. The Department of Energy says reducing drafts alone can save 10-20% a year on energy (energy.gov). Bring a flashlight, a notepad and, if you have one, a plug-in energy meter.
Before you start
- Pull 12 months of bills to see your usage pattern. A big winter spike means heating; a summer spike means cooling. See how to read your bill.
- Pick a cold or windy day: leaks are easier to feel.
- Turn off fuel-burning appliances’ thermostats if you plan a “depressurization” test (see below).
Checklist 1: Air leaks
- Feel for drafts at baseboards, where walls meet ceilings, around windows and doors, outlets and switch plates on exterior walls, plumbing and wiring holes, and the fireplace damper.
- Look for daylight around door frames and gaps in weatherstripping.
- Optional test: on a cool, windy day close all windows and doors, turn on bathroom and kitchen exhaust fans, then move a lit incense stick around suspect spots. Smoke that wavers points to a leak.
Fix: caulk, foam and weatherstripping. Details in insulation and air sealing.
Checklist 2: Safety with fuel-burning appliances
The DOE warns that a tighter house can cause furnaces, water heaters and fireplaces to backdraft. Look for soot or burn marks near appliances. The DOE rule of thumb: one square inch of vent opening per 1,000 Btu of appliance input. Have a pro check combustion appliances after major sealing, and keep CO alarms working.
Checklist 3: Insulation
- Attic: if the insulation is level with or below the ceiling joists, add more. Check that the attic hatch is insulated and sealed.
- Basement and crawl space: DOE recommends at least R-25; the foundation perimeter R-19 or more.
- Ducts in attics or crawl spaces: at least R-6, and seal dirty-streaked seams with duct mastic.
- Walls: with power to the outlet turned off at the breaker (and confirmed off), remove an exterior-wall outlet cover and look into the gap with a flashlight.
Checklist 4: Heating and cooling equipment
- Replace furnace or heat pump filters every one to two months in heavy-use seasons.
- Book a professional check-up about once a year.
- Systems older than about 15 years are worth pricing replacements for, per DOE. See heat pump installation cost.
Checklist 5: Lighting and electronics
- Lighting is about 10% of a typical electric bill (DOE). Replace remaining incandescent and halogen bulbs with LEDs.
- Use a plug-in meter to find devices drawing power while “off”. See phantom power.
Turn findings into a plan
| Priority | Typical fixes |
|---|---|
| Do this week | Weatherstripping, caulk, outlet gaskets, LED bulbs, filter change |
| Do this season | Attic air sealing and insulation, duct sealing |
| Plan for | Heating system or water heater replacement, windows |
When you’re ready for a deeper look, many utilities offer a professional assessment with a blower-door test at low or no cost, the DOE notes.
FAQ
DIY or professional? DIY finds the obvious problems; a pro with a blower door and infrared camera finds the hidden ones and checks combustion safety.