Test your windows and doors for airtightness. Move a lighted candle around the frames and sashes of your windows. If the flame dances around, you need caulking and/or weatherstripping.
Insulate. No matter how you heat or cool your home, you can reduce the load on your heating and cooling equipment by as much as 20 to 30 percent by investing a few hundred dollars in insulation. The benefits of insulation – lower utility costs – continue for years.
Clean or replace filters regularly. Keep outside units free of leaves or debris that may clog vents.
Use kitchen, bath, and other ventilating fans sparingly. In just 1 hour these fans can blow away a houseful of warmed/cooled air. Turn them off just as soon as they have done their job.
Keep your fireplace damper closed when not in use. An open damper in a 48-inch square fireplace can let up to 8 percent of your heat out of the chimney.
Consider installing an energy-efficient heat pump, if you use an electric furnace for heating. The heat pump uses thermal energy from outside air for both heating and cooling.
Don’t let cold air seep out of your home through the attic access door.
Keep draperies and shades in sunny windows closed in summer to help keep out the heat.
Use double-pane glass throughout the house. Windows with double-pane heat-reflecting or heat-absorbing glass provide additional energy saving, especially in south and west exposures. If replacement windows are too expensive, consider installing storm windows and doors.