Sustainable housing solutions by design

Researchers at the University of Waterloo have reimagined the construction of modular homes with the development and testing of an innovative new design that allows the structures to be more easily relocated, reassembled and reconfigured in either urban or remote areas.

The design of the Structural Timber and Applied Research Team (START), located in Waterloo’s Faculty of Engineering, uses cross-laminated timber (CLT) and a wall-to-floor connection with few bolts needed in each connection. Unlike traditional fasteners, the novel connector plate was intentionally designed for ease of disassembly and reassembly, ideal for multiple reuses and relocations.

The demand for flexible housing options — compounded by concerns about climate change and its impact on vulnerable communities — is spurring the need for inventive solutions that can expedite the deployment of safe, sustainable and affordable homes. The ability to reuse walls and other parts means fewer materials end up in landfills. The lightweight and durable CLT is ideal for modular housing in remote areas with limited road access. The system is conceived to be transported in a flat pack arrangement and be assembled using little to no heavy equipment.

“Our goal is to redefine how modular buildings are conceived and implemented,” said Dr. Daniel Lacroix, a professor in the Department of Civil and Environmental Engineering (CEE) at Waterloo and lead on the project. “We are leveraging mass timber in combination with other lightweight and sustainable materials to create a system that can be assembled, disassembled and reassembled without compromising structural integrity or affordability.”

START's connector runs counter to common design methodology as it is purposefully designed to allow for multiple reuses and relocations. Moving away from the use of multiple small fasteners closely spaced allowed the team to develop a connector that is practical for disassembly and reassembly.

The researchers tested the strength of their design by standing two CLT panels measuring 2 meters by 2.8 meters upright in a lateral design setup and pushing on it with 60 kN of force, which far exceeds the lateral forces each panel would usually experience. In testing, the novel wall-to-floor connection system proved fit for reuse following several cycles of loading, disassembly and reassembly. 

“Reuse means less waste and fewer carbon emissions, so our design’s reusability is an important step forward in circular economy construction methods,” said Daniela Roscetti, who led the research as part of her master’s thesis under the supervision of Lacroix and Dr. Andrea Atkins, a professor in CEE.

START plans to refine their design and conduct rigorous testing in the next stage of development. The team is pursuing partnership and funding opportunities.