The design/build model presents architects with distinct advantages in custom residential work—accurate pricing, streamlined construction documents, and exclusive control over the finished product. And architect-led design/build firms, like conventional custom builders, can avoid the overhead of a large field crew by subcontracting some or all of the production work. Cleveland-based design/build architects Michelle and Alexander Kolbe have seized on these benefits while adding a twist of their own. Along with Bensonwood—an established builder in Walpole, N.H.—they combine custom design and personal attention with the quality control and efficiency of panelized, prefabricated construction.
The Kolbes’ firm, evoDOMUS, works to serve clients “who don’t want to get involved with more than one company,” Alexander Kolbe says. Sample designs on the firm’s website are primarily inspiration for potential clients. “We design each home individually, from scratch,” he says. “Then we work up a budget, and clients decide whether to build with us or not.” For those who choose to proceed, this is where things get interesting.
Teaming up beats subbing out
While evoDOMUS is overseeing site preparation and foundation work, Bensonwood is fabricating the building’s structure in its climate-controlled indoor production facility. Structural panels arrive at the site shrink-wrapped in plastic. A Bensonwood crew assembles the building shell, performs a blower-door test, and hands off the project to evoDOMUS’ finish crew. “It’s a hybrid process,” Kolbe explains. “Everything inside the house is built in the field … and we hand the owners the keys to a finished home. We’re the only point of contact for the client, and that’s a big thing for the people we work with.”
The custom prefab approach follows a model that is common in Germany, where Alexander Kolbe grew up (he and his American-born wife met while practicing architecture in Berlin). “We worked with some of the top German [prefab] manufacturers for many years,” he says, and they grew to appreciate the design advantages of panelization over the methods more common in the U.S. modular buildings, which “all have this boxy, containerlike thing going.” Using panels, in contrast, “we have no size limitation; we have no span limitation; we can do anything.”
Prefab’s benefits go beyond saving money
On its website, evoDOMUS makes a strong case for prefabrication, but an appeal to bargain hunters isn’t part of the pitch. The method can indeed be more cost efficient than conventional site-built construction, Kolbe explains, but its greatest benefits lie in time efficiency and construction quality. “We build the most precious part of the house, the load-bearing structure, in a controlled environment,” with the advantages of CNC fabrication equipment in an optimal-humidity atmosphere. The resulting precision is key to meeting the firm’s stringent performance standards. With rubber gaskets sealing structural joints and triple-glazed German windows, “we get blower-door results below 1” air change per hour, he says. Photovoltaic panels power the buildings’ air-source heat pumps, “so we don’t need fossil fuels.”
Partnering offers distinct benefits to fledgling firms
Leveraging Bensonwood’s expertise and industry standing gave evoDOMUS a leg up in the business and played to the smaller company’s strengths. “We want to keep our company small and exclusive, so we can spend a lot of time with each client,” Kolbe says. While evoDOMUS has been in business less than three years, Bensonwood’s manufacturing capabilities and reputation as a pioneer in both prefabrication and green building provided market presence, credibility, and geographical reach right out of the box. “We focus on the East Coast, simply because it’s close,” Kolbe says, “but we work everywhere. If you twist my arm, I’ll build you a house in Alaska.”