Robots help streamline new home construction
With workers scarce, builders turn to the next best thing
BALTIMORE – The construction of an American house embodies the spirit of the nation’s workers and the dreams of its citizens.
It also is perhaps the least-efficient endeavor in the U.S. economy.
Dozens of workers turn a plot of land into a small factory, sawing wood, nailing it together, cutting holes for windows, running wires and pipes and installing drywall and other finishes. Four months or so later, voila: A home for generations of families.
Now, a worsening construction worker shortage that has driven up home prices is beginning to turn that routine – largely unchanged over the past century – on its head.
At a factory owned by Blueprint Robotics on the industrial outskirts of this city, a house frame is chiseled in large panels by computerized machines in about a day. The pieces of walls, floors and roof are then trucked to the construction site to be assembled in several more days. Although drywall and other features must still be added, the process can shave the time to build a house by as much as half.
A new generation of prefabricated housing is among several technologies homebuilders are embracing to cope with the worker shortage.
“We’re at a tipping point where it’s finally just gotten too expensive to build the old-fashioned way,” says Margaret Whelan, CEO of Whelan Advisory and an investment banker for the home building industry.
Last year, at least half of homebuilders reported a serious shortage of framing crews, carpenters, bricklayers and other tradespeople, according to a survey by the National Association of Home Builders. The worker deficit is a big reason NAHB counted a four-month supply of existing homes in April, below a balanced six-month inventory. The limited stock has helped drive up home prices nearly 50 percent since 2012, according to the S&P CoreLogic CaseShiller index.
While hundreds of factory-built homes have been put up the past couple of years, up to 20 percent of houses could be prefabricated in five years, says Stephen Kim, a senior housing analyst for Evercore ISI, a research firm.
The industry is due for a fresh approach. While U.S. productivity, or output per labor hour, rose an average 1.76 percent a year from 1995 to 2015, productivity in construction declined an average 1.04 percent during that period, according to an Evercore analysis of government and McKinsey Global Institute figures. Contractors are vulnerable to weather, human error and the missteps that result when dozens of unrelated subcontractors join forces to cobble together a home.
The new manufacturers, who serve as suppliers to traditional builders, make flat panels and can churn out any blueprint the builder requests.
At Blueprint Robotics, about 30 software engineers and architects convert builders’ plans into programs that computerized machines follow. The machines, robots essentially, cut wood to length, form holes and grooves for electric sockets and wiring, nail the wall studs at precise intervals, then add holes for windows and doors.
Tasks that could take traditional workers an hour or more are completed in minutes.
At the construction site, it takes about a week for a crane and seven Blueprint workers to lift the panels into place and bind the frame so the homebuilder can complete the house.
New Jersey builder Robert Kiejdan recently hired Blueprint to help put up a 2,700-square-foot house in Margate. He says it normally takes his subcontractors up to six weeks to construct the shell that Blueprint turns out. After factoring in delays, he estimates the house will be completed in three months instead of the usual six.
“I think this will be a significant change in the way houses are built.”
Stephen Kim
A senior housing analyst for Evercore ISI