LIKE MANY PROJECTS OF MASSIVE scope, the New Urban Challenge sounded deceptively simple at its inception: design and build a 2,300-square-foot house to mirror the square footage of the average new house built in America. Put it on a tight lot in a high-density development because that's where the building industry is headed. That by itself probably would have been enough for any builder to undertake.

But good ideas have a way of growing, and the New Urban Challenge was no exception. Working with Houston-based production builder David Weekley Homes, Builder and Home magazines decided to give three top architects the same square footage and lot size, with the thought that they would each design a house for the same hypothetical buyer.

That was a better idea but still not quite everything it could be. So the idea grew again. Each architect ultimately was charged with designing a house for a different buyer demographic—a family with two young children, a professional couple with no children, and an active adult, empty-nester couple.

The homes would be built side by side in Orlando, Fla.'s Baldwin Park. The 1,100-acre community is built on the site of the former Orlando Naval Training Center and is one of the largest infill redevelopment projects in the United States. The houses would front a park-like mews on 45-by-120 lots with detached, alley-loaded garages. Not only would there be strict architectural guidelines to follow, but the houses would also need to help the owners simplify their lives and meet their desire to form an emotional and spiritual connection with the place they call home—and incorporate products and services from 44 national sponsors.

The response from the architects was intensely personal. They designed houses they would want to live in themselves.

Seattle-based architect Bill Kreager immediately chose the active adult buyer and continually referred to it during design and construction as “our house.” The Shingled Cottage, with its master bedroom on the main level, is first and foremost a gathering place for friends and far-flung family, with cozy window seats that grandchildren can delight in, no less than four distinct gathering spaces, and a garage apartment geared to the minimalist needs of a returning college student.

Geoffrey Mouen, who fled New York to Central Florida with his young family because he and his wife longed to raise their twins themselves instead of leaving the children in the hands of a nanny, designed the Classic Residence. It features a massive front porch that functions as an outdoor living room, his-and-hers master baths, a quiet retreat off a family-centric kitchen and great room, and a kid-friendly playroom above the garage.

New York City urbanite Donald Rattner created a sophisticated Mediterranean-inspired Villa for a Modern Couple, a pair of professionals with gourmet tastes and a passion for entertaining. An inviting loggia is the entry point to a spectacular two-story great room, abundant flex space, a dramatic second-floor mezzanine, and a contemporary media room above the garage for upscale social events.

“The architects weren't given restrictions of creating houses that can be stamped out in a mass-produced way,” says David Pace, the managing director of Baldwin Park. “We said, ‘Show us how to take a small house and (make it) live large so people who would buy a larger house would look at this and not feel they're compromising.' These are incredibly good houses. Each of these houses is almost like a roll-top desk you live in. There is no space that's not cleverly used.”

Bob Rohde, vice president of design at David Weekley Homes, says the houses also represent the full range of today's home buying market. Putting them next to each other creates unique opportunities for building community across the generations.

Learn more about markets featured in this article: Orlando, FL.