Americans spend $160 billion each year to heat, cool, light and live in their homes, according to a survey by the Propane Education and Research Council.

See Air Leaks | Efficient Appliances | Slash Bills

Could you save more of that? Sure. But how much energy homeowners conserve in their home depends on how much time, money and effort they want to put into it.

Finding out how much work and cost is involved means knowing how energy efficient your home is now.

An energy audit can help troubleshoot where heat is escaping from the home.

Organizations such as the Alliance to Save Energy offer links to free online calculators to compute a home's energy efficiency, home energy checkup lists and do-it-yourself home energy audits. Or you can pay from $100 to $300 to have a professional do it.

"Our primary goal is to find where warm air leaks out from a building," said Erik Lindberg, president and co-founder of Enervision, an energy-auditing company in Minneapolis.

Lindberg said that most people focus on cold air leaking in, but it's more effective to keep warm air from leaking out because heat loss represents cost.

He said if you stop the exit of warm air, you will also stop cold air from coming in.

As part of the energy audit, Lindberg uses an infrared camera to scan the upper part of the building for air leaks, among other things.

"The images are almost like X-rays," Lindberg said. "We can tell whether there's insulation or not, and whether there are air leaks and how to eliminate them."

His process involves a pressure test to find out how "tight" the house is and find leakage areas. Lindberg said he also looks at consumption issues and figures out how much energy is being used to heat the house.

"(It) gives you realistic goals for improvement," he said.

Why Conserve?

Why do homeowners choose to conserve energy and buy energy-efficient appliances? The biggest incentive is to save money by cutting high utility bills.

But there are other benefits that many people might not realize.

Rozanne Weissman, director of communications and marketing at the Alliance to Save Energy, said taking steps to improve energy usage lowers the overall energy price; decreases harmful emissions and all types of air pollution; increases energy security -- and can make a home more comfortable.

Lindberg said people should be concerned about their home's energy usage so they can save money; if the house is unevenly heated or drafty, they might be concerned about the distribution of heat in the house, which can prevent roof damage from ice dams forming. An ice dam is a ridge of ice that forms at the edge of a roof and prevents melting snow from draining off the roof. The water that backs up behind the dam can leak into a home and cause damage to walls, ceilings, insulation, and other areas

Ice dams occur, Lindberg said, when about 12 inches of snow accumulates on the roof, then it warms up from interior ceiling below then trickles under the gutter and then refreezes, then water starts to go under the shingles.

There are several means of improving a home's energy efficiency that range from a few bucks to thousands of dollars. People can choose the level based on their pocketbook.

No-Cost Steps

There are several easy steps that will cost homeowners nothing but their time.

• Close the fireplace damper. If the damper is open, the heat gets sucked out of the house. For wood-burning fireplaces, consumers may want a glass fireplace screen in front to prevent more heat from escaping.
  "It saves you an incredible amount. That's like a big hole in your wallet," said Al Garrett, director of training at House Doctors Handyman Service.
• Open curtains during the daytime.
  "If you open the curtains on the sunny side of the house, it saves you more money than you realize," Garrett said.

Low-Cost Steps

While it may cost you money in the short term, some fixes will cost less if you tackle them right away.

• For starters, take a look at the shell of the home. Weissman said heating the home is half of family's energy bill, so anything they can do to make sure heat is not escaping the home can cut down that cost.
  "Check your home's first line of defense against the elements," Weissman said.
  Doing that helps to find out the sources of cold drafts.
  Scott Morgan, host of HGTV's "Dream Builders" and spokesman for the Propane Education and Research Council, suggested walking around the house with a candle. When the flame flickers, it indicates drafts.
• Weissman said to seal leaks between the moving parts of doors by putting weather stripping around the door where it meets the frame.
• Garrett said to buy a door broom that mounts on the inside of the door.
  "Homeowners with a screwdriver can install it in 15 minutes," Garrett said.
• Seal cracks in the home's nonmoving parts, such as doors and walls.
• Morgan said if the home has old windows, they should be reglazed where the panes meet the glass.
  "I am the world's biggest fan of sealing with silicone sealant both on the inside and outside. You'll notice a tremendous difference," he said.
• Garrett said old, wood-framed single-pane windows are a good candidate for plastic covering on the interior, giving them another closed air barrier. The covering can also reduce condensation. Kits are sold at hardware stores.
  It involves using double-sided tape around the window frame, then taking a sheet of clear plastic and applying it to the tape. Garrett suggested taking a hair dryer and running it over the plastic to further seal it.
• Garrett said that depending on the design of the home, there are insulated light switch covers that can cut down on drafts seeping in.
• Weissman said to put timers on lights in a home so the light isn't on all day. Switching to energy-efficient light bulbs can also help.
• With big-ticket items such as a furnace system, Garrett recommended spending a few dollars annually on maintenance to prevent costly repairs. He said to seal any seams in a metal duct system with tape or putty to make the system efficient.
  The California Energy Commission's Consumer Energy Center stressed not to use duct tape to seal the ducts.
  A technician can also help detect whether carbon monoxide is coming into the house through heating system.
• Clean and replace the furnace's air filter each month. This will also help the furnace's accompanying air conditioning system.
• If the furnace operates on short cycles, Lindberg recommended having it looked at by a technician.
  "It's like your car. If it starts and stops, it doesn't get good economy," he said.
• Regulating the heating or cooling system with a programmable thermostat can be a big step in controlling the home's temperature.
  Programmable thermostats allow homeowners to set the exact temperature for different blocks of time during a 24-hour period.
  An hour before bedtime, set it to 65 degrees or less, and an hour before getting up, set it to 68 degrees. During the day, set it to 65 degrees, and in the late afternoon or evening, set it to 68 degrees, according to the Propane Education and Research Council.
  Consumers can save as much as 10 percent annually on heating and cooling bills by turning the thermostat back 10 percent to 15 percent for eight hours a day, according to the council's Web site.
• Garrett said to insulate any exposed water pipes and the water heater so the water won't get as cold as fast, which will save energy.
  "You can drop as much as 5 to 10 percent of your water bill. It adds up a lot more than people realize," he said.
  Newer water heaters might not need insulation.
  "I don't recommend wrapping the water heater. It was commonly recommended years ago, but most modern water heaters are better insulated. Most prohibit wrapping because they are afraid it will overheat," Lindberg said.
  To keep the water heater from having to work harder to heat up water, cut down the extremes to which it has go.
  Morgan said if there's a thermostat on the hot water heater, to drop it 5 percent from 120 to 115 degrees to keep the water warm all day long. He said if the water heater doesn't have a thermostat, to adjust it to the lower side of medium.

Pricier Steps And Tax Credits

Adding insulation or spray foam can be key to helping the house's heating and cooling system run more efficiently. And by doing so, homeowners may be eligible for federal tax credits.

Garrett said older homes were lightly insulated, if at all.

"A lot of products used were not permanent insulators and go away with age," he said.

States have different thresholds of insulating power levels, or R-values, which tell consumers the level of insulation they should install. These levels should meet the criteria for the federal tax credit, according to the NAIMA Web site.

Fiberglass and mineral wool insulation have the highest R-values. The new R-value of the insulation installed can be added to the R-value of the insulation that's already there to meet the state standard, according to the National American Insulation Manufacturers Association Web site.

The tax credit allows for up to a $500 tax break on 10 percent spent on eligible energy efficiency upgrades, such as insulation, not including installation fees, and it must be installed between Jan. 1, 2006 and Dec. 31, 2007 to claim the credit on your 2006 tax returns, the NAIMA Web site says.

Areas to consider when bolstering insulation are attics, attic doors, walls and even crawlspaces if there are cold floors.

Garrett said the insulation in crawlspaces will often fall between floor joists, so it's good to check to see if the insulation is in place.

"It's not a hard job, but it's not a pleasant one, either," he said.

For long-term energy savings, homeowners may want to consider upgrading to more energy-efficient high-ticket items for their home.

Under the Energy Policy Act of 2005, these items are eligible for tax breaks: storm windows; windows; skylights; exterior doors; storm doors; metal roofs; insulation; central air-conditioning units; air source heat pumps; geothermal heat pumps; gas, oil orpropane furnaces; hot water boilers and water heaters. For details on the type of tax credits offered, see Energy Star's guide.

When considering new windows, Morgan suggested low-emissions windows, which have two panes with thermal glass that have a break in the middle. He said the center is typically filled with argon gas, which keeps condensation at bay and makes a noticeable difference in drafts and heat loss.

One way to cut down how hard your water heater must work is with a tankless hot water system.

Morgan said it is the size of a medicine cabinet and it doesn't require replumbing. He said the portable tank runs on natural gas and propane. Instead of heating 50 to 80 gallons of water, it's on-demand hot water, and within seven seconds, there's hot water available on four floors of a home.

A pricey alternative to overhauling a home heating and cooling system is using a geothermal pump that draws heat from the earth into the home.

Lindberg said geothermal pumps are becoming more common with new homes.

"Ground source heat pumps are fairly expensive and the payback is lengthy," Lindberg said.

No matter what consumers spend to save energy or increase the home's energy efficiency, every step can help keep down the overall cost.

Heating costs may be dropping, but they have not come down to what they once were, Weissman said.

"Heating costs may be lower than last year, but ... the average U.S. household will be spending nearly $5,000 for the year 2006 to power our homes," she said. "It's 32 percent above what it was two years ago because our energy expenses have really gone up." More Resources:

• Get Your Home Ready For Winter's Chill
• DIY Home Audit
• Home Energy Checkup Calculator
• Free Low-Cost Ways To Save Energy
• Self Home Audit With Children
• Energy Star Guide To Energy Efficient Heating And Cooling