Metateps

Add some insulation. If you're building a new home, exceed the local recommendation for insulating walls and ceilings. It will cut down on both heating and cooling bills. Also, insulate hot-water and hot-air ducts and pipes that provide heat around the house. Put a thermostat-controlled fan in the attic to exhaust hot air.

Replace ordinary single-glazed windows with argon-filled double-glazed or thermopane windows. Storm windows and doors significantly reduce heat loss. Covering the window frame inside with clear plastic does the same job, but be wary when the weather warms up: The temperatures between the glass and the plastic can cause the glass to crack if it's hit by cold rain, and can melt any plastic imprisoned between the two layers. Commercial reflective films can screen out heat without significantly reducing the light coming through, or the view out of the window. Add some exterior awnings over south-facing windows. Drapes and shades will buffer the home from heat and cold.

Paint your house an appropriate color. Dark shades are better in cold environments, as they collect more heat; light shades are best in warm climates, reflecting solar energy.

Weatherize your home with caulk and weather stripping to block air leaks around doors, windows, and cracks in the walls.