Unlike houses built on-site using framed structures or prefab panels, modular buildings are constructed almost entirely in a factory. Volumetric “boxes” are built by skilled tradespeople and trucked to a prepared construction site, a process that proponents say reduces waste and deployment time. Even mega-landlord Greystar recently hopped on the modular bandwagon with several new multifamily residential projects, leading one to ask: Can modular help us end the housing crisis?

Jon Hannah-Spacagna, the director of government affairs for the Modular Building Institute (MBI)—a trade association for allied professionals working in and around modular buildings—certainly thinks so. His role is to further MBI’s advocacy work, to collaborate with elected officials and government agencies, and educate the built environment sector on modular’s possibilities. Speaking with Dwell, Hannah-Spacagna explains the pros of building your house (or office) in a factory, dispels some rumors about code-related issues, and discusses what needs to change if cities want to rapidly make a dent in our country’s missing six million units of housing.

Dwell: For those unfamiliar with modular building, can you explain what it is?

Jon Hannah-Spacagna: We’re not a product, we’re a process. A modular home is built to the same building codes as a site-built home—or whatever type of construction you want to think of. If we can build it modularly in a factory, it’s being built to those same standards that a site-built construction crew would build. It’s just simply that we build it in three dimensional, volumetric boxes, and then they are transported to the site and then craned into place.

I’d love to hear a little bit about why modular building is a good process, or better than traditional building.

We’ve had independent studies done that show our type of construction is greener, so there’s less waste and less emissions. Because we’re building a factory setting, we’re literally utilizing every piece of material that we procure for that project. And if there’s something that isn’t used, then it’s put to the side and used on the next project. The other part is the safety of the construction workers: If you went into any modular manufacturing facility, you’re not going to see any of those workers on scaffolding; they’re able to build these modules on a ground setting and move them from station to station. Everything from the exterior and floor construction to the mechanical, electrical, and plumbing that goes into them—even the furniture, in some cases—they’re built in a controlled setting, then trucked to the site. So it’s much safer for the employees.

As I’ve toured many of our member factories, an interesting thing you see are people that you wouldn’t normally see on a construction site. You may see a disabled veteran in a wheelchair working at a modular construction station. You may see a lot more women in the workplace in a modular factory than you would on a construction site.

“It’s a matter of educating people on our industry, what we have to offer, and why modular is a good solution for housing.”
—Jon Hannah-Spacagna

You say that modular buildings are built to the same standards as site-builds; what about the facilities themselves? How are they regulated?

Facilities are inspected by state approved inspection agencies, and in some cases, the state actually sends their own people to inspect them. The factories have to be certified by the state that they're doing business in, in addition to each individual module being inspected and receiving a label from that state, if the state has a modular program. Some don’t, and those that don’t, then you work with the state building official to get those approved, but the factory has to submit their quality control manuals and get their own certification before they even start building a specific project.

When did modular building become a widespread practice?

Modular has been around since the old Sears catalog days; you could literally order a modular home in a Sears catalog back in the ’60s. [It’s resurgence] is due to a combination of [factors], from the marketing that we do out of our office, to the world of modular events in Las Vegas, which has been going on for many, many years. We continue to see record growth for that event year after year. I’m getting phone calls and emails almost on a daily basis—from government agencies, nonprofits that are building, housing developers wanting to learn more, investment companies that are looking to invest in modular construction and modular manufacturers. Once they have success with modular, they see the value of not only the quicker return on their investment, but also all the benefits that I’ve mentioned. And it really is a faster, greener, better way to build, and with the declining workforce that we have in the construction industry now—because we're not seeing kids coming out of school wanting to go into construction like they did 30 years ago—it’s going to have to be the way of the future for how construction is done.

What are some of the biggest hurdles that the modular industry encounters?

It’s a PR misunderstanding of what modular construction is. And that goes from the consumer, who may be looking to build their first home, to the developer who may be building 100 homes on a specific lot, to a governor or member of Congress who is looking for ways to solve our housing crisis. It’s a matter of educating them on our industry, what we have to offer, and why modular is a good solution for housing.

But there are states that are taking that and running with it, like Colorado. We’ve worked with them for the past several years; they passed legislation a couple years ago that created $40 million in grants specifically to support the build of affordable housing using modular construction. And those grants were for existing modular manufacturers to expand their capacity and footprint and also to recruit new modular manufacturers to move to their state. They’ve also added low-income housing tax credits and other financial funding streams to support modular, and in the last three years, they’ve increased modular production by 687 percent. I would say 99 percent of that is focused on affordable housing.

In Canada, we’ve seen great success: I worked with the Canadian Mortgage Housing Corporation right after the pandemic. They created what they called their rapid housing initiative. It started out as a $1.7 billion investment using only modular construction to build affordable housing, and in the first 24 months, they created 10,000 new housing units for those in need. So it’s a proof of concept that it works.

You work at a national level, so when you’re thinking about different cities, what are some of the most common code related challenges? Are there disparities around what could be built in Chicago, versus Denver, versus Atlanta?

The easy answer is, that’s a misperception. We’re built to the same building codes as site-built construction. There are two code books that you reference—either the International Residential Code through the International Code Council, which is specifically for residential, single family residences, or the International Building Code through the International Code Council, which is specific to commercial or multi family modular construction. So every state in the U.S. adopts those building code standards. Most of them will have some amendments. It could be specific to wind, seismic, snow requirements. That’s what site-built contractors build to, and that's what our industry builds to. You won’t talk to pretty much anyone in our industry that says we want special or different building codes for modular—we can build to any building code in whatever state you want us to.

Most of our manufacturers are regionally dispersed. For example, if they’re based in Texas, they could build for California, Colorado, and Louisiana; they can build anywhere as long as they know beforehand which state it’s going to and the building codes you need to comply with. We can do that. So that’s not a hurdle. It’s really the education piece to help people. We don’t have a building code problem and right now in both of those codes that I mentioned, the word modular does not exist. As an organization, we partnered with the International Code Council, and developed standards. So there’s ICC MBI standards, and not to get too far in the weeds and codes, but those were developed to help building officials understand our industry.

We’re pro-anything that supports getting housing built faster. What are the possibilities for modular when it comes to fitting into existing or possible plans to remedy the housing crisis?

For those that are wanting to really address housing, commit a set dollar amount and partner with the modular construction industry and modular manufacturers to say, “hey, for the next three years, five years, whatever it is, we want you to build X number of homes.” We had manufacturers that just built 200 homes in Maui for FEMA as a part of the fire disaster relief. And they said, Okay, here are the designs. We want you to build one, two, and three bedroom homes. We need 200 of them. Here’s how many of each. And here’s the money. Our manufacturers built 200 homes in 60 days. They had all the means in place logistically. Some of these were constructed in Colorado, some in Idaho, and they were shipped or transported to the port in Seattle, loaded on a barge, transported to Maui, offloaded, and then set on site. They are beautiful one, two, and three bedroom homes. To me, it is what should be done, and how you’re going to maximize productivity.

Top photo courtesy of MBI

Factory photo courtesy of Inherent Homes

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