“The current system can’t meet demand and that’s resulting in a lack of opportunity for some folks and a major hit to the economy,” said Stonly Baptiste, a co-founder of Urban Us, a Brooklyn-based venture capital firm that invested in Blokable. “These aren’t small problems and they aren’t small markets.”

The technologies vary but generally involve simplifying construction through prefabricated panels that can be assembled like Ikea furniture and modular apartments that can be stacked together like Lego bricks. A recent survey by FMI, a management-consulting and investment banking company focused on the engineering and construction industry, found a third of respondents said they were looking at some form of off-site construction, a steep rise from 2010. The interest extends from housing to hotels to medical facilities, industrial companies and even fast-food restaurants.

“It’s one of those things that looks like an overnight success but it’s taken 10 years and hundreds of people toiling,” said Chris Giattina, chief executive of BLOX, a Birmingham, Ala., company that builds hospitals with modular components.

Brokers of Risk

The global construction industry is a $10 trillion behemoth whose structures determine where people live, how they get to work and what cities look like. It is also one of the world’s least efficient businesses. The construction productivity rate — how much building workers do for each hour of labor they put in — has been flat since 1945, according to the McKinsey Global Institute. Over that period, sectors like agriculture, manufacturing and retail saw their productivity rates surge by as much as 1,500 percent. In other words, while the rest of the economy has been supercharged by machines, computers and robots, construction companies are about as efficient as they were in World War II.

To understand this, consider how buildings are actually built. It all starts with the developer, who doesn’t actually build anything but instead secures a piece of land and a loan, and gets the project approved by the government. At that point the money is passed to the general contractor that made a successful bid to build the project, who passes it to subcontractors that won the bidding for things like plumbing and sheet metal work, which often pass it to even more subcontractors.

Contractors describe this handoff as “brokering risk.” What they mean is that while everyone in the chain has agreed to build a certain piece of the project for a set amount of money and in a given amount of time, none of them are sure they can do so as cheaply or quickly as they’ve promised. They broker that risk by paying someone else to do it for them, minus a small fee.