Sweden has mastered the art of building homes and apartments in factories, similar to assembling Ikea furniture. This efficient, industrialized construction method produces modular units that are trucked to sites and quickly assembled into complete buildings. However, the approach used in Sweden presents a complex lesson for the United States, which is grappling with a severe housing shortage.
Swedish factories produce modular rooms, such as kitchens and bathrooms, complete with plumbing, wiring, and appliances. These components are then transported and crane-lifted into place, forming entire single-family or multi-family structures. One development of 114 apartments was assembled on-site in about five weeks. According to industry estimates, a significant portion of new Swedish homes utilize some form of prefabrication, with around 90 percent of new single-family homes built with prefabricated timber systems and 43 percent of multifamily apartments constructed with fully prefabricated structural frames.
Despite its success, the "Ikea method" of home construction is not readily available in the US. Experts suggest that simply replicating Swedish factories in America would be misguided. Instead, the focus should be on addressing the underlying regulatory and zoning issues that hinder innovation in US homebuilding.
A History of Mass-Produced Housing
Both Sweden and the US experimented with accelerated prefabricated building in the 1960s. Sweden's "Million Homes Program" (1965-1974) incentivized builders to use innovative methods, leading to the construction of over a million homes and fostering a culture of industrialized construction (IC). This approach builds on Sweden's long history of experimenting with factory-made houses, dating back to the 1820s.
The US launched "Operation Breakthrough" in 1969, aiming to speed up and reduce housing costs through factory-based methods. While it resulted in over 30,000 housing units, the program disbanded in the mid-1970s, failing to establish a widespread IC market. However, Operation Breakthrough contributed to the development of a national building code for manufactured homes (often called "mobile homes"), which now represent about 10 percent of US single-family home construction and are among the most affordable housing options.
Regulatory Hurdles in the US
A key difference between Sweden and the US lies in their building codes. Sweden employs performance-based codes, which set safety outcome standards, allowing developers flexibility in how they meet them. This fosters innovation and has enabled Sweden to build tall wooden apartment buildings that would likely face significant hurdles in the US due to more prescriptive codes that often specify exact materials and methods.
Conversely, US building codes are frequently criticized for being prescriptive and adding unnecessary costs without proportional safety benefits. The fragmented nature of US building codes across thousands of jurisdictions also makes it difficult for factory-based builders to achieve economies of scale by selling standardized designs nationwide. Experts argue that outdated requirements within these codes, designed with traditional construction in mind, create barriers for prefabricated systems.
The Potential of Manufactured Homes
While Sweden's regulatory environment may have inadvertently fostered innovation, the US already has a substantial factory-based housing industry in manufactured homes. These homes are regulated by the HUD Code, a nationally consistent, performance-based federal code that exempts them from local building codes, though not zoning requirements. The affordability of manufactured homes suggests the cost-saving potential of prefabrication and uniform codes.
Recent legislative changes in the US aim to further integrate manufactured homes. The "ROAD to Housing Act" removed the requirement for a permanent steel chassis, making these homes less visually distinct from conventional houses and potentially reducing discrimination. HUD is also exploring expanding the code to allow for multi-unit manufactured housing, which could significantly impact the availability of affordable, industrialized housing options.
While Sweden offers a model for industrialized construction, the path forward for the US likely involves reforming its complex web of building and zoning regulations. Addressing these fundamental issues, rather than solely focusing on importing foreign technologies, could unlock greater innovation and affordability in American homebuilding.