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The construction industry has a conundrum. It’s one of the few industries in the United States struggling to improve productivity.

鈥淲e’re actually looking at a crazy dichotomy where construction over the past number of years has actually lost productivity,鈥� said Jonathan Orpin, founder and president of New Energy Works Timberframers and Pioneer Millworks 鈥� both based in Southeast Portland.

That’s one of the fundamental drivers, he added, behind continued exploration of prefabrication in construction. Another reason is the worsening housing crisis across the country. Many project teams are seeking new ways to drive down the costs of development, whether residential or commercial.

While prefabrication of various building components is taking place in piecemeal fashion across the industry, one specific solution could be found in building enclosure systems. Pre-panelization is slowly gaining popularity, in part because project designs are being developed virtually with building information modeling (BIM) software.

This topic was explored Thursday at Pioneer Millworks’ warehouse as part of Design Week Portland. There, Orpin was joined by Nathan Young of Mods PDX, a manufacturer of modular buildings, and Geoff Sosebee of Lever Architecture, who has designed several cross-laminated timber projects involving prefabrication.

鈥淲ider use of BIM, automation, it’s coming, but slower than almost any other industry,鈥� Orpin said. 鈥淒evelopers are pushing this need too, and in the last few years we’re finally seeing a big investment.鈥�

Orpin pointed to Katerra. The Bay Area startup, around four years old, is now worth $1.2 billion. It dived headfirst into offsite construction as part of an end-to-end business model that includes design, materials, procurement, offsite manufacturing and construction.

As for modular construction, Young said, the engineering goal is to reduce to a minimum the number of prefabricated components needed to complete a building. This also makes prefabrication better suited for multistory buildings with repetitive units or those with remote locations or where construction is particularly disruptive.

鈥淥ur belief is that 80 percent of every building is exactly the same,鈥� Young said. 鈥淎nd the more we can standardize that, the more we can use offsite production to lower those costs.鈥�

Part of the problem in finding more efficiency in prefabrication 鈥� whether panelized walls, cross-laminated timber or other types of systems 鈥� comes on the factory floor. In terms of both technology and scale, there is much remaining to be desired.

鈥淲e’ve been doing pre-panelized roof and wall systems since 1993, and it’s evolved since then, but we’re still working in a reasonably rough shop setting as opposed to what I saw during my recent trip to Europe,鈥� Orpin said.

In Western Europe, at least, he added, roughly 35 percent of single-family homes are built using offsite construction; in the United States that figure is less than 1 percent.

That number is driven by manufacturing efficiencies unseen in the U.S. In one European factory, Orpin said, the average production rate is 150 single-family homes per year using a labor force of eight production floor workers and four office staffers. The use of automated storage and nailing machines, robotics and other technology accounts for additional labor, time and fiscal savings.

鈥淚t was a very telling moment,鈥� he said.

The industry is still fighting the cost issue, Young added, even though prefabrication ensures better quality by virtue of components being built to higher tolerances and in controlled settings instead of a job site open to the weather.

鈥淲e haven’t mechanized to the full advantage of where we could be compared to Europe,鈥� he said. 鈥淎nd part of that is that it requires standardization which we don’t have in America; we’re not quite there yet.鈥�