How long things last

Want to know when your old furnace or washing machine is going to give out? Here are a few guesstimates.

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Moreover, appliances are often replaced long before they are worn out because changes in styling, technology and consumer preferences make newer products more desirable.

The National Association of Home Builders' "Study of Life Expectancy of Home Components" gives a decent guesttimate by compiling life-cycle data from scores of product manufacturers and testing labs.

Of the major appliances in a home, gas ranges have the longest life expectancy: 15 years. Dryers and refrigerators last about 13 years.

Some of the appliances with the shortest lifespan are: compactors (6 years), dishwashers (9 years) and microwave ovens (9 years).