In This Series

Humans have dreamed for years of a future where all the work would be done by machines. At the Keene, N.H., manufacturing plant of Unity Homes and Bensonwood, that future is one step closer to becoming a reality. The plant cranks out complete home frames, bundled for assembly on site, including walls, roofs, and floors. There’s still plenty of work in the facility for people. But much of the fabrication, along with all of the heavy lifting, is done by high-precision machinery (see photos). On a tour of the facility, JLC got to see some of the equipment in action as Hans Porschitz, Unity’s chief operations officer, explained the setup.

Mortise-and-tenon joinery substitutes for steel connectors in some situations; here, Hans Porschitz demonstrates a mortised porch-roof connection.
Mortise-and-tenon joinery substitutes for steel connectors in some situations; here, Hans Porschitz demonstrates a mortised porch-roof connection.
Brad Ramsey, the Hundegger CNC equipment operator, works the controls for the machine. Also at Ramsey’s fingertips is the control panel for the Joulin semi-automatic vacuum feeding system, which allows him to select and feed a variety of materials from a magazine into the cutting equipment.
Brad Ramsey, the Hundegger CNC equipment operator, works the controls for the machine. Also at Ramsey’s fingertips is the control panel for the Joulin semi-automatic vacuum feeding system, which allows him to select and feed a variety of materials from a magazine into the cutting equipment.
Alex Morin assembles the framing for a window rough opening. This component will then get fed into the automated framing system that will frame the other parts of the wall.
Alex Morin assembles the framing for a window rough opening. This component will then get fed into the automated framing system that will frame the other parts of the wall.
The CNC bridge gantry is equipped with nailers and a router. It travels over the wall on the table, fastening the sheathing to the framing and trimming it to the final panel size as well as cutting out the sheathing for any door and window openings.
The CNC bridge gantry is equipped with nailers and a router. It travels over the wall on the table, fastening the sheathing to the framing and trimming it to the final panel size as well as cutting out the sheathing for any door and window openings.

At the heart of the operation is a Hundegger Speed Cut SC3, a versatile robot that gets its instruction directly from a home’s CAD design file. Workers load the machine with raw materials using a vacuum-lift crane. The Speed Cut can handle solid beams as fat as 7 inches by 24 inches and has no trouble with wood I-joists or glue-laminated stock. Inside the machine, a spinning saw blade makes all the necessary cuts for stud, joist, and rafter framing. Routers can hog out mortises and tenons or holes for chases. Cuts are precise to 1/16 inch. And the Speed Cut’s ink-jet printer not only labels every part that’s cut, it also handles layout for wall, floor, and roof panel assembly. Workers who put the components together rarely have to touch even a tape measure or pencil.

Jason Furland places insulating fiber sheathing on the exterior of a wall panel. The gantry will nail off and trim the panel later.
Jason Furland places insulating fiber sheathing on the exterior of a wall panel. The gantry will nail off and trim the panel later.
Ray Zabel installs the standard sill pan detail of a doorway rough opening prior to the door install.
Ray Zabel installs the standard sill pan detail of a doorway rough opening prior to the door install.
All doors and windows are detailed and installed before the walls are shipped, allowing the home to be blower-door tested as soon as the last panel is installed in the field. Greg Bruns preps the exterior of the rough opening for a window, using Siga tape.
All doors and windows are detailed and installed before the walls are shipped, allowing the home to be blower-door tested as soon as the last panel is installed in the field. Greg Bruns preps the exterior of the rough opening for a window, using Siga tape.
All wall panels are fully airtight and watertight when they are shipped to the field. A worker manhandles parts for a custom curved roof package created by the Hundegger Speed Cut saw. The Unity Homes plant is capable of accomplishing fully panelized building shapes ranging from simple geometric forms to one-off architectdesigned creations.
All wall panels are fully airtight and watertight when they are shipped to the field. A worker manhandles parts for a custom curved roof package created by the Hundegger Speed Cut saw. The Unity Homes plant is capable of accomplishing fully panelized building shapes ranging from simple geometric forms to one-off architectdesigned creations.

From the Hundegger, parts are bundled and carried by forklift to three parallel assembly lines: one for walls, one for roofs, and one for the “open cavity” components (interior walls and floors). During assembly work, operators don’t have to bend over or lift heavy weights, because machines handle the lifting. And operators seldom touch a tool; they just place parts on the framing table. Machines nail studs to wall plates. Workers do have to tack sheathing in place (although they don’t have to lift it), but automated routers handle the sheathing cuts, and rack-mounted nail guns nail the material off with precision accuracy.

Read Next >> Built in a Factory, Assembled on Site