Causes of air leakage.
Source: U.S. Department of Energy

"Air sealing" was perhaps the top energy-saving concept on the lists of all the experts we interviewed. They all agreed that elimination of air leaks, wherever you find them, will help you reduce energy costs.

Jerry Nash, from the State of Michigan's Energy Office said that when trying to conserve energy at home, reducing air infiltration will produce "the best return on your investment."

In winter, you want to seal the heat in and make sure the cold stays out. Stopping drafts also makes you feel more comfortable, and that helps you resist turning up the thermostat.

In general, air leaks around moving parts (windows and doors) can be closed with weather stripping, while caulk is used for sealing leaky gaps between non-moving parts -- such as window frames and walls.

Cellulose and fiberglass insulation typically used in attic spaces and other areas "can slow down air flow, but they don't stop air leaks," said Phil Smith, an energy specialist from the Minnesota Department of Public Service. "There is a thermal boundary between the heated space and the unheated space. That's where you want to make your air seals."

Smith recommends that you first turn your attention to the attic area, where air leaks can be "astoundingly" significant. "Change the lid first, and you change the physics of the building to your advantage."

Stressing the importance of slowing the movement of air and moisture between heated and unheated spaces, Smith termed the area above the ceilings in rooms right under the attic "a sort of DMZ."

Not only should those places be well insulated, but the insulation should be protected by a vapor barrier to keep moisture from passing through it into the unheated space. Smith noted that in the past, ceilings were usually covered with oil paint which had vapor retardant qualities -- something lacking in many newer, acrylic-based paints.

According to Smith, often overlooked places for air leaks into the attic include:

• Spaces around electrical and plumbing penetrations (such as the vent pipe)
• Area above light fixtures, especially recessed ones
• Spaces above dropped ceilings as well as the soffits above bath or kitchen cabinets
• Any other areas where walls are not completely sealed at the attic, such as stairway walls and interior partition walls
• Attic doors, which should be insulated, weather stripped, and closed tightly to stop heated air from escaping into the attic. Smith says this should be "the tightest door in the house."
• Chimney chase ways. While no combustible material, including insulation, should be closer than two inches from the chimney, a draft blocker made of sheet metal can be installed and sealed with specialized caulk that can withstand very high temperatures
  

Foam draft blockers (gaskets) for electric outlet and wall switch boxes are easy to install, inexpensive and widely available. According to Chris Carroll from the State of Maine Energy Conservation Division, "Studies have found that one to two percent of air driven infiltration can come from two-whole outlet boxes and switches."
Drafty windows can be sealed with removable window insulation in the form of storm window kits available at a hardware store. These kits are used to install a clear shrink-wrap plastic film on the insides of your windows and seal them from drafts.
Window quilts (also called insulated window shades) can be used to cut the cost of keeping your house warm in the winter, cool in the summer.
Check the condition of existing caulk and weather stripping. Remove and replace any materials that have deteriorated. Caulk that is cracked or shrunken is no longer effective.
Get a cover for any air conditioners installed in your outside walls or windows.
Make sure that all inside window sashes are locked; it tightens the seal.
Keep the fireplace damper closed when no fire is burning, and consider glass doors to prevent interior heat from entering the chimney.

Another major utility savings can be had by turning down the thermostat in the winter and leaving it at least 81 in the summer.

This tip is the one you hear most often -- and it's a simple, effective way to cut your heating costs. Indeed, experts we talked with agreed that many households can cut heating bills by 20% or more by lowering your from 70 to 65 degrees when you're home, and to 55 when you're asleep or away or leave it up to 81 when your away in the summer.

Turned down furnaces use less electricity/fule and should be cleaned and tuned up once a year by a qualified service person.

Alll wood burning systems should be inspected by a solid fuel technician, and chimneys should be inspected and cleaned annually.

Other energy savers?

If you heat using hot air:

• Check ductwork for leaks and separations.
• Sealing duct joints, with mastic or high quality non-cloth-backed tape\
• Insulating ducts in unheated spaces can reduce energy loss. Duct work that is not well sealed can also reduce the systems cooling efficiency.
• Filters should be cleaned or replaced monthly. A dirty filter can block air flow, and heat can be lost through the chimney
• Heating outlets have plastic deflectors installed -- they will direct heated air into the room.
• Don't block radiators and baseboard heaters or registers with draperies or furniture. It's also a good idea to vacuum them regularly -- dust reduces their efficiency.
• During the day, open draperies and window shades on the sunny side of the house to capture warmth. Or velcro sun shade to the outside of your windows to keep it cool in the summer. Close them at night to keep cool/heat in.
• Don't waste energy by heating closets and unused rooms Close them off.
• Keep fireplace dampers closed when no fire is burning, and consider glass doors to prevent interior heat from entering the chimney.
  

How to save on your Hot Water Bills:

• Insulate your hot water pipes and tank -- but make sure not to cover up the tank's thermostat.
• The Department of Energy recommends that you lower your water heater temperature to 120 degrees.
• Electric water heaters often have two thermostats-one each for the upper and lower heating elements. These should be adjusted to the same level to prevent one element from doing all the work and wearing out prematurely.
• Drain a quart of water from your hot water tank every 3 months. This will remove sediment that prevents heat transfer and lowers the heater's efficiency.
• Installing low-flow faucets and showerheads will reduce hot water consumption.
• Repair leaky faucets promptly. They waste gallons of water in a short time. A leaky a hot water faucet just sends your energy dollars down the drain.
  

How to save on your Electric Bills:

• Compact fluorescent lamps (CFLs) can be a big money-saver,CFLs fit in a normal light socket and are four times as energy efficient as a regular incandescent bulb and last from six to ten thousand hours. That makes them especially useful in outdoor fixture. Over its life, a CFL that costs $22 will pay for itself plus $35.
• In their booklet "PowerSmart: Easy Tips to Save Money and the Planet," the Alliance to Save Energy notes that replacing as few as four 100-watt incandescent bulbs with four comparable 23-watt compact fluorescent bulbs would save $82 over three years
• Dimmer controls and three-way light switches save energy by allowing you to choose the light level you need.
• Inspect the seals on refrigerator and freezer doors. If they aren't airtight, your appliances aren't running efficiently. Check the gaskets by closing the door on a dollar bill. If it pulls out easily, you probably need a new gasket. Also remember that dust accumulating on the coils at the back (or bottom) of the unit should be brushed off regularly.
• The perfect time to use the self-cleaning feature of an oven is right after you finish baking -- while the oven is still hot. That way the oven will need less energy to get to the proper cleaning temperature. Try not to use the self-cleaning feature too often.
• Don't use the drying cycle of your automatic dishwasher. Allowing the dishes to air dry will cut energy use significantly. If your machine doesn't have an air-dry option, stop the machine after the final rinse and prop open the door to help the dishes dry faster.
• Periodically check your the vent and lint filters on your clothes dryer to make sure they aren't blocked. Not only will this save energy, but it may also prevent a fire.