By Cheryl Weber. So-called flex spaces have been a consumer-friendly feature in floor plans for nearly 10 years. But never before have buyers had so much freedom to design their home without changing its envelope. In the beginning, builders might have offered a bonus room over the garage or French doors that transform a bedroom to a den. But now they're experimenting with floor plans that can be stretched, flopped, twisted, and added to. A house has become a product line in layout, as well as amenities.

"What's happened is that flex spaces are proliferating because we're understanding that with the variety of different buyer profiles, everyone will live a little differently," says Sean Degen, vice president of architectural services for Pulte Homes, in Bloomfield Hills, Mich.

This out-of-the-box thinking may have started with the quintessential question of whether or not buyers want a formal living room. Next, the dining room came up for grabs. "A lot of first-time buyers don't have a formal dining set, so they might use the dining room as a kids' playroom until they inherit a table," Degen says. Put on French doors and -- presto -- there's the playroom. Add high-speed wiring and the owners have an office.

Home on the Range

Flex and bonus spaces are a key ingredient in the designs of David Weekley Homes, based in Houston. "We do it to show that our homes are more flexible and usable than others," says chairman and CEO David Weekley.

Photo: Courtesy Morrison Homes

Personal Touch: Morrison Homes puts interactive floor plans on its Web site to attract buyers. By clicking the shaded flex spaces on this house plan in an Orlando, Fla., community, consumers can tailor the layout to the way they live.

"It's meant as a competitive advantage." He estimates that 50 percent of the company's home buyers add some type of bonus space. "Both bonus and flex spaces are an important profit center," Weekley adds. "Any adjustments we make, we have a margin on." Modern-day consumers might want to live less formally, but they don't want to sacrifice square footage. Young families who opt for an office in the designated dining room often add a sunroom off the breakfast and kitchen areas, says Bob Rohde, vice president of product design for David Weekley Homes.

On the other hand, empty-nesters purchasing a four-bedroom house in the upper price ranges prefer to fold one of the bedrooms into a 300-square-foot master suite, which the company calls a super-master. The luxuries add up, with a large shower, dual vanities, and his and hers walk-in closets. In homes priced $250,000 and up, one of the builder's most popular options is adding livable space in the attic. "We do a lot of one-stories here in Texas," Rohde says. "With these big attics, we can add 500 to 600 square feet for $25,000. Most of the cost is already there for us; we're just beefing up some structure and adding carpet."

The possibilities extend as far as imagination, logistics, and local building codes will allow. In the Southwest and West, Pulte Homes offers a three-car garage in which the third bay can be converted to a pool cabana.

For Remington Homes, in Chicago, architect Mike Kephart, of Kephart Architects in Denver, designed a flex courtyard for the middle units of a townhouse complex. Buyers can choose between the courtyard and a living room or great room. "The middle units went from being the poorest selling to the best selling," Kephart says.

Of course, there are costs associated with allowing such flexibility. Weekley uses a comprehensive computerized system that captures cost data, prices the spaces accordingly, and replicates buyers' choices on purchase orders and sub agreements. The sales person and the contractor also meet face to face to ensure clear communication. "The biggest issue for us is communicating those decisions and getting materials ordered, making sure everyone is on the same page," Rohde says.

Selling Agility

Flexible floor plans are also changing the way builders approach sales and marketing. Rohde says he has to think about the plan portfolio in a different way. If a 2,400-square-foot home has a 500-square-foot bonus room, is it competing with a 2,900-square-foot home? "You have to analyze the value of one home compared to the other," he says. "Maybe it's a different plan type or targets a different buyer."

Last year, Atlanta-based Morrison Homes began using interactive floor plans to draw customers through the Internet. Shoppers spinning through one of the builder's 600 online plans can click on a menu of options to add a garage or fireplace or turn a fourth bedroom into a den. John Rymer, vice president of sales and marketing, found that visitors stayed on the company's Web site 20 percent longer when they had interactive plans to play with. And the longer people stayed on the Web site, the more likely they were to walk into a sales center.

"The idea is that people can do this 24/7 and configure the home before they come in," Rymer says. "Even though we did this before, people didn't know it until they walked in the showroom. People are intimidated by sales people."

Although David Weekley's buyers can view and print plans via the Internet, virtual design isn't in the works yet. "We're not sure we want to go there," Weekley says. "We want people to come in and see and touch and feel. Our sales folks are really consultants in every stretch of the word, helping buyers come up with a home that exactly fits their needs."