Washington ? Thank goodness for fickle consumers and their changing tastes.

Their constant itch to refresh and remodel their homes keeps the makers of toilets, cabinets, countertops and more in business, which in turn helps keep the economy humming.

Never mind if many of these things do not need replacing. In a recent study, the National Association of Home Builders (NAHB) detailed the life expectancy of roofs, floors and everything in between and found that some components, such as doors, can last decades if cared for properly.

The study’s goal: inform people about how many years they can reasonably expect from those parts so they can better preserve their homes’ value. Behavioral experts suggest that durability is closely linked in the consumer psyche to quality and a feeling of permanence that embodies the very meaning of home.

So why is it that consumers crave longevity yet junk their cabinets, faucets and appliances long before they wear out?

“People want a whole range of things to last a long time, even emotions,” said Daniel Ariely, a behavioral economist at the Massachusetts Institute of Technology. “But they seldom account for the time gap between their initial decision to acquire something and their decision to replace it later.”

During that gap, people change. So do their tastes, desires and lifestyles. Manufacturers are forever catering to, counting on and even encouraging those changes as they try to improve their sales.

Consider faucets. The ones in kitchens should last 15 years on average, while the ones in bathrooms should last about 20, the NAHB study concluded based on comments from about a dozen faucet manufacturers.

Yet only about 30 percent of residential faucets sold each year replace ones that are broken or worn, said Jack Suvak, marketing research director at Moen, a maker of kitchen and bath products. The rest are split between newly built homes and remodeling projects, wherein people typically start replacing their fixtures a couple of years after moving in.

“Most homeowners are not comfortable with what they inherited,” Suvak said. “They want to make it their own.”

Then there’s the pocketbook factor. Not everyone can afford the top-of-the-line, longest-lasting products, which is why some consumers might settle for asphalt shingle roofs, for instance, instead of paying for more durable copper roofs, Racki said.

But the long term is important, said Frank Lesh, president of the American Society of Home Inspectors. Think about your house as you would a car, he urged. “It’s like a machine. And machines wear out.”

So pace yourself. Adopt what Lesh calls “the 1 percent rule” when it comes to your home’s upkeep: Budget 1 percent of the value of your home each year for maintenance.