A decorated shed

The one-room house designed by a team from the Massachusetts Institute of Technology (MIT) benefited from many of the same digital processes behind the Cellophane project, but with a completely different result. Instead of a Modernist dwelling of novel materials, Digitally Fabricated Housing for New Orleans is a pitched roof cottage made largely of plywood and adorned with a decorative frieze.

The 350-square-foot dwelling's form and its traditional ornament were controversial among faculty members at MIT, according to Larry Sass, an assistant professor in the school's department of architecture and the leader of the project team. "When I first showed my ornate models to a few colleagues, some were appalled that my work did not reflect the Modern movement in architecture," he says.

For Sass and his students, however, there was no requirement that a prefabricated house conform to a particular language. "This delivery system and digital process is not limited to one architectural style," says Daniel Smithwick, one of Sass's research assistants. "It can produce a Modernist cube just as easily as a Victorian mansion," he says. 

 

Â
A team from MIT developed a house for New Orleans (1) with a digital model (2 and 3) and a series of physical models and full-scale prototypes. The resulting structure is composed of bilateral ribs, largely of plywood, with some high-density polyethylene elements (4). The pieces were assembled on-site with rubber mallets (5 and 6) and are held together by friction, rather than nails, bolts, or other mechanical fasteners. Photo courtesy Larry Sass/MIT

 

 

The MIT prototype has a structure of bilateral ribs made of more than 4,500 pieces milled from plywood with a computer numerically controlled (CNC) cutting machine-one that relies on digital information to direct the selective removal of material. Over three weeks, the installation team of Smithwick and fellow research assistant Dennis Michaud put the house's notched pieces together on the MoMA lot with rubber mallets. Friction between the elements' tabs, slots, and grooves holds them together, rather than bolts, nails, or other mechanical fasteners. They also applied glue to key joints, though it is not critical to the building's structural integrity, according to Michaud. "It was a concession to the engineer," he says.

Sass and his students developed the "snap-and-fit" assemblies with a combination of parametric modeling and BIM. The resulting digital model described the geometry of the house's components, but also took into account criteria such as material behavior, manufacturing processes, and the sequence of assembly. Along the way, they tested and adjusted the digital model with a series of small-scale physical models and full-scale prototypes made through laser cutting, CNC-milling, and 3D printing. With the refined digital model, they then cut the building's actual components from 600 sheets of plywood at a lumber yard in Exmore, Virginia.

Once the components were delivered to MoMA in mid-June, assembly proceeded relatively smoothly. However, the interface between the prefabricated foundations and the traditionally constructed slab-on-grade presented a slight glitch. Although Sass and his team had accounted for irregularities in site conditions by designing base blocks that allowed adjustment, they did not know in which direction to move the blocks until several days into assembly, when some parts were not fitting correctly. At that point, they needed a forklift to nudge the already constructed portions of the house together. Almost all of the teams had similar difficulties, according to Jay Gorman, project manager for F.J. Sciame, MoMA's construction manager. "Meeting the ground is one of the challenges of prefab," he says.