With her signature ingenuity, architect Maryann Thompson combines two Chestnut Hill duplexes to create a handsome home.

The modest Dutch colonial in Chestnut Hill was quite an anomaly for this neighborhood of stately homes and grand trees. It had been designed as a twinned duplex for servants' quarters in the early 1900s, and, unlike other area residences, had survived the luxury development boom. Harvey Makadon had lived in one half of the strange little house since 1983 and considered himself lucky to be able to afford the pricey neighborhood. He was especially lucky when his partner, Raymond Powrie, decided to buy the other half in 2006. "We were very worried about the fate of this house," says Powrie. "By buying the other half of the building, we ensured that nobody would come along, tear it down, and build a great big mansion."

On the advice of a friend, they talked with Maryann Thompson of her eponymous architecture firm about merging the houses into a single-family home without disrupting the feel of the original structure. "She seemed to understand that we wanted to respect the house's integrity," Makadon says. "It's really a little cottage. We didn't want to lose that sense of scale and proportion."

Thompson took a philosophical approach to the challenge of creating a contemporary living space while retaining the character of the original structure. "You start with something that's early 1900s, and layer onto it a statement of the era we're living in now. That these things can live side-by-side is a hopeful way to look at the world," she says. "It's an attitude that supports multiplicity." Her first move was to keep the double entry somewhat intact. "Rather than masking the reality that this used to be a two-family house," Thompson says, "we're celebrating what makes it unusual."

Just inside the front door sits a wood statue that Powrie found at an antique store in Chiang Mai, in northern Thailand. "Putting the statue there was like framing a picture," Powrie says, referring to how the statue unifies the space. It's one of many objects the couple, both physicians, bought during their travels for work and pleasure, but Makadon and Powrie bristle at being called art collectors. "We don't go out looking to buy certain things," Makadon says. "The driving force is our own taste. It's our vision of what we like that brings everything together."

Nevertheless, Thompson's first instinct was to design for the pair's impressive large-format photographic prints, pottery, and antiques—but Powrie and Makadon preferred a more organic design process. "When the house was finished, we had no idea where anything would go. We just looked around and started placing objects," says Makadon.

The Thai statue sits at the bottom of the two mirrored staircases—one leads to a guest area with a bedroom and bathroom; the other leads to a shared study with extensive built-in millwork and a master suite.

An informal dining area adjacent to the kitchen is enclosed by floor-to-ceiling glass, creating the feeling of a screened-in porch. The kitchen features bleached walnut cabinets and a green tile backsplash. Throughout the first floor, Thompson used Brazilian slate and whitewashed oak flooring. The muted palette provides a perfect backdrop for the art collection, elegant but far from ostentatious.

"They cautioned us not to overdo it," says Zac Cardwell, project manager at Maryann Thompson Architects. "They preserved the house, even [as they opened up the space]. They preserved their own personalities in the renovation, as well."

The success of the design has a lot to do with improved flow, says Powrie, and Makadon agrees. "Before the renovation, we didn't use the space all that well," he says. "It was small and cramped. Now I find that we use more of the house and it works better."