Difra Thinks Different about House Design and Construction

Wouldn’t it be great to design and build your own personal house, real cheap? It may sound like a dream, but not for much longer. Difra, a Cambridge, MA, company co-founded by graduates of MIT, is working hard to fulfill this ambition.

Their idea is to use computer-aided design and manufacturing software (CAD-CAM) to model new houses in 3D, then translate the designs into kits containing all the flat 2D components needed to build them—in this case, engineered wood boards that interlock via so-called “friction joints.”

“To transform 3D to 2D for a typical, average-sized house of 1,600 square feet consisting of several thousands individual components is a very demanding task if done manually,” says Difra co-founder Morris Cox. But automation cuts the cost and the complication down to size.

Difra will sell its system directly to individual home buyers—and it already has some clients lined up. “Although our aim is to provide ordinary people with personalized homes, we will initially build more luxury homes, to show what can be done and gain acceptance among a broader audience,” says  Cox.

“My dream is to enable people, even on limited budgets, to personalize their homes, to allow freedom in design,” adds Cox’s co-founder Lynwood Walker. “Light and color, form and feeling, we let people have it the way they want it.”

A model of Difra's prototype cottageThe team dug into a CAD system called Rhino—chosen for its ability to model surfaces and export data as CAM files that can be used in fabrication machines—and wrote algorithms that translate designs into practical plans that can be built using friction joints, which fit together using only glue.

Once a Rhino model is transformed into drawings of the fundamental 2D components, the 2D files are fed to a laser cutting machine. Pieces are cut and numbered by the machine. All the pieces are neatly packed and sent to the construction site, together with assembly instructions.

“Building a home is like laying out a giant 3D-puzzle”, says Cox. “It is the perfect community project. Most of it can be done by ordinary people. We see it as a rewarding and socially enriching project for neighbors, relatives or other groups.”

Cox estimates that a small house or cottage can be put together in no more than