Washington area builders have found a way to squeeze more homes onto each acre of land by building houses that are thinner and longer than conventional models.

At a time when local land prices are at a premium, some builders and architects are experimenting with a design called "narrow-wides," in which 40-foot-wide homes are built on 50-foot-wide lots that run 100 feet deep. Typical subdivision houses are 60 to 65 feet wide on 80- to 100-foot-wide lots.

As a result of the thinner designs, builders are able to construct as many as six single-family detached houses per acre, two more than with traditional quarter-acre zoning. The narrow houses are made possible because most local zoning regulations require only minimal distances between the sides of homes and are arranged in a way to give each house some sense of individual identity and access from a street.

The downside of the design is that the houses usually have 10- or 20-foot garages in the front, sometimes dominating the designs and creating what some builders and architects call "garagescapes."

On the other hand, builders say, narrow-wide designs allow detached homes with more privacy than is possible in a town house complex.

"The concept is a coming thing, because land is so expensive that you have to build on smaller and smaller lots," said William (Chip) Benson, vice president of Ruxton Homes, which is considering building such homes. "The characteristic of these homes is that they're much deeper than they are wide. It's just the opposite of what most people are used to. But in time we're going to see a lot more of them."

Fairfield Homes, L.J. Hooker Homes, Pulte Homes and Richmarr are among the area builders constructing 40- to 60-foot-wide houses costing $200,000 to $400,000 that are built on lots of between 5,000 and 6,000 square feet.

Builders are targeting two types of buyers: Those already living in town houses who want more space, and those living in large houses who want smaller ones.

One of the motivations for building narrow-wides has been the rising cost of land. According to real estate economist Michael Sumichrast, land prices, environmental and permit costs now amount to about 25 percent of the total cost of a house, up from about 11 percent in the 1950s.

In the Washington area, where the average price of a new house is $175,300, the land and permit costs total $43,825. In short, builders are being forced to make the best use of their land while still providing privacy, some degree of luxury and innovative design.

In Reston, Fairfield Homes is offering its first narrow-wide models in a 58-unit project called Old Brookville. One reason the company chose to build such houses is that it already has a town house project within a few miles of the Old Brookville development.

"We didn't want to build any more town houses," said Jerry Aubrey, a Fairfield Homes sales manager. "We wanted to reach the market that was between the town house buyer and the single-family home buyer."

Fairfield's two models are the Bridgewater and the Oyster Bay, which cost between $220,000 and $230,000. Each has a single-car garage, vaulted ceilings and plenty of windows. There are five homes per acre, which allows for between 15 feet and 18 feet between each house.

"They're built to create a village cluster like in Cape Cod," Aubrey said. "They're a great alternative"The concept is a coming thing, because land is so expensive that you have to build on smaller and smaller lots." Ruxton Homes' William Benson

when the kids are gone or you want something a little bit more than a town house. People are kind of surprised when they see them. They find they're a lot bigger than they really appear and they like the floor plans."

George Bean, the sales manager for L.J. Hooker's Fairways at Penderbrook, said he was skeptical at first about how well the design would sell.

Hooker is building three styles of houses on the fairways of the Penderbrook Golf Course near Fair Oaks, the huge shopping mall at Rte. 50 and West Ox Road. The models aren't expected to be completed until March, but Bean said 11 of the planned 89 houses have been sold.

Each two-story house has a two-car garage, a fireplace, oak floors and a full basement; prices range from $337,000 to $367,000.

The houses are larger than typical narrow-wides, which average about 2,000 square feet. The Ashburton is 2,817 square feet, the Berkshire 2,624 and the Collingsworth 3,244.

"I've been selling homes for 14 years and was a little dubious at first," Bean said. "Most people like to buy something that's been built before.

"But I've been amazed," he said. "Most people buying haven't been looking for big lots and usually one or both people are golfers. They're designed to look as attractive from the rear as they are from the front."

Jean Palmer, sales manager for The Greens, a Pulte Homes project at Penderbrook, said she calls narrow-wides a sort of "contemporary carriage house. It's just a different style house."

Pulte is building 47 homes starting at $299,900. Each of the homes is between 2,200 square feet and 4,800 square feet. Like the Fairfield models, there are lots of windows, skylights and decks.

But Mark Humphreys, executive vice president for Womack-Humphreys Architects, said that despite the trend, buyers are still cautious about the design.

"If you put a two-car garage on these very narrow lots, it really doesn't leave much house," he said. "There tends to be some resistance from buyers who may feel they're buying a lot of garage for a couple hundred thousand dollars."