How long

Major Mechanical Systems

Routine maintenance--such as cleaning furnace or air-conditioner filters and scheduling periodic service--
might be the only practical way a homeowner can extend the life of major mechanical systems. "Those
things go a long way toward making these units last longer," says Gary Kemp, a sales representative at Bell
Brothers Heating and Air Conditioning in Des Moines, Iowa.

Water quality plays a role in the longevity of boilers, water heaters and water pumps. Water that is highly
acidic or full of minerals is tougher on equipment than treated water, and life spans should be lowered
accordingly. This is the case in many rural parts of the country, where houses often have their own wells.
For heating systems, boilers last longer than hot-air systems because the water helps to moderate heat
extremes, making hot and cold cycles less stressful on the equipment.

Building Structure

Calculating the life expectancy of a roof, siding, exterior paint, flashing and the like is far from an exact
science. Geography plays an important role. For example, a wood-shingle roof that wears like iron in a
moderate climate might succumb much more quickly when exposed to constant dampness, harsh sunlight
or other environmental extremes. Another key factor is the quality of the material. Vertical-grain wood
siding cut from the heartwood of trees naturally resistant to decay, such as western red cedar, will last far
longer than plain-sawn lumber of lesser quality. The trade-off is a higher initial cost, a factor if you don't plan
on being in the house that long. Finally, there is the question of workmanship. Even the most expensive
paint in the world won't last long when applied to an improperly prepped wall.

Roofing-replacement costs are especially complicated to predict. Not only are there many grades of roofing
material, but the job might also call for demolition, flashing, gutters and sheathing. Complicated roof shapes
drive costs up, too.

Appliances

Most of us have run across an ancient refrigerator or range in someone's kitchen that's still working
flawlessly long after it should have been hauled to the dump. Like most statistical summaries, the chart
showing the life expectancy of major appliances is based on averages. With an estimated 600 million
appliances at work in American households, there will be plenty of exceptions. In fact, the Association of
Home Appliances Manufacturers says most appliances are not junked at all. A majority are sold, traded in,
left behind in a move or given away, and they faithfully serve second or even third owners. As a result,
according to the trade group, how long these household workhorses actually last is impossible to say.

Americans spend more than $15 billion a year on new appliances. Very expensive, restaurant-quality
appliances are increasingly popular. The estimated retail prices above, however, are for products from
Whirlpool and General Electric, two widely available brands

(check the price of dozens of models on their Websites). You can spend a lot more if you want.

GE's Terry Dunn says any appliance that uses water will benefit from a water softener and water-filtration
system. "Fewer chemicals and minerals will prolong the life and improve the performance," he explains.

Tips for prolonging life for other appliances:

Clean the condenser coils on refrigerators annually.

Change air-conditioner filters monthly during the operating season.

Replace washer fill hoses every five years; turn off the water supply when away for an extended period.
Drain hoses if below-freezing temperatures are expected.

Inspect and clean the exhaust duct on the clothes dryer at least once a year, and clean the lint filter before
each use.

Don't allow heavy grease buildup on the oven interior.