In November 2020, First Community Housing and SERA Architects announced a partnership to build a 66-unit housing project in Morgan Hill, California. The building will use modular construction techniques, and 100% of the units will be used as affordable housing, helping to address the state’s housing shortage for low-income families. Healthy Building Network is working closely with SERA Architects to provide healthier materials recommendations in alignment with the project’s LEED Platinum certification ambitions.
This project offers a chance to explore healthier material solutions that leverage the technologies and standardized processes that are characteristic, or at least available to, the modular construction industry.
What is modular construction?
Modular construction is a process in which a building unit (Volumetric), or its parts (Non-Volumetric), are constructed off-site under controlled conditions and installed at the construction site. While meeting the same building code regulations as traditional (i.e., on-site) construction methods, proponents of modular construction argue that the process can result in significant reductions of time, cost, waste, and need for specialized labor. As a result, modular construction has the potential to disrupt an industry that remains one of the top contributors to waste and carbon emissions and boasts productivity levels that have remained largely unchanged for decades.
But how can the modular construction industry leverage its standardized processes, measures, and parts to advance the transition to a more circular and toxic-free built environment?
To answer these questions, I look through the lenses of adaptability, traceability, and scalability, in search for opportunities at the intersection between modular construction, circular economy, and the healthier buildings movement.
Plan for disassembly and design for adaptability
While designing parts for disassembly is not a technique that is unique to modular construction, it can benefit from the standardization of processes and parts that are characteristic of off-site construction methods. The use of mechanical connections, as opposed to chemical ones, reduces material contamination and damage during deconstruction.1 This means that buildings designed for disassembly can facilitate the recovery and reuse of building materials while reducing the manufacturing and usage of toxic adhesives and the amount of toxic waste reaching our landfills.
Designing for disassembly maximizes the flexibility and future adaptability of buildings. It extends their life beyond their initial design by increasing a building’s responsiveness to changing demands. For renters of affordable housing, this means housing units that can effectively cater to a family's changing needs, including growth in the number of family members or changes to their economic conditions.2 In addition to improving a resident’s quality of life, adaptable design leads to an overall reduction in the production and use of building materials, including toxic exposures associated with their manufacturing, installation, and disposal. Due to the use of standard measures and modular design, modular buildings can play a pivotal role in supporting adaptable and healthy design strategies.
Demand transparency and invest in traceability
In contrast to traditional construction techniques, modular construction leverages a centralized supply chain that provides greater oversight of the materials that are used. By procuring materials that meet transparency requirements (e.g., HPD and Declare labels) and integrating RFID technology into prefabricated parts, the modular construction industry has the opportunity to create a closed-loop supply chain that maximizes the life and value of materials, particularly those that meet transparency and healthier criteria requirements. Thus, coupling transparency requirements with technology-enabled traceability can strengthen the business case for healthier materials (i.e., demonstrate higher ROI) and act as a virtuous cycle that boosts the demand for material transparency.
Volume and scalability
Modular construction’s increased efficiency and use of an assembly-line format encourages bulk procurement of materials at the start of a project. Modular construction can leverage economies of scale to procure healthier materials at prices that meet affordability requirements. An increased demand for healthier materials can incentivize manufacturers to invest in R&D efforts that result not only in further optimization of building products, but more efficient manufacturing processes that further reduce the cost of healthier options.
According to David Johnson, Principal at SERA Architects, “Working with a modular housing manufacturer requires the design team to creatively adapt to a "standard" set of options and systems that are part of the manufacturer’s modular system very early in the design process. Because the manufacturer’s preferred materials and products are also fairly ‘standard,’ there is an opportunity for the design team to evaluate and assess the material health aspects of those products very early in the design process, leaving time for optimization where needed.”
In reference to the First Community Housing project, David indicates that “HBN's collaboration on a very early deep assessment of the modular housing standard material specifications was tremendously helpful. This early guidance is now allowing us to focus on specific areas of the modular design to strategically craft the greatest positive impact on material health aspects of the project, within the practical reality of the budgetary constraints. In our work together, HBN and SERA benefit from the support of First Community Housing, and their steadfast commitment to providing beautiful, affordable, durable, healthy, and delightful homes for families.”
Transitioning to a healthier modular construction environment requires a multi-stakeholder approach. We need policies that increase the demand for modular housing projects and promote regulatory frameworks that incentivize material transparency and safer chemistry. Major cities like San Francisco, Oakland, and New York City are already committing to invest in the development and preservation of affordable housing using modular construction techniques.3 At the same time, many states, and cities like New York, are requiring developers who access public dollars to pursue green building certifications that prioritize the use of healthier materials, such as Enterprise's Green Communities Criteria. The interplay between financial incentives, market security, and green and healthy affordable housing standards can set the stage for a thriving and safer modular construction industry.
I believe there is a great opportunity for the modular construction industry to help tackle the affordable housing crisis while delivering healthier homes. Should it commit to doing so, it needs to start by making healthier materials a priority and building a cohesive supply chain that places human and environmental health at the center of its operations. At the core, this means breaking away from the script of “construction as usual” and forging an operating model that pursues, rather than ignores, environmental justice.
Editor's Note 3/31/21: This post was updated to correct the location and unit count of the First Community Housing and SERA Architects project.
 Minunno, Roberto, Timothy O’Grady, Gregory M. Morrison, Richard L. Gruner, and Michael Colling. Strategies for Applying the Circular Economy to Prefabricated Buildings. Buildings 8, no. 9 (09, 2018). doi:http://dx.doi.org.proxy.lib.duke.edu/10.3390/buildings8090125.
 American Institute of Architects (AIA). Buildings that last: Design for adaptability, Deconstruction, and Reuse. PDF file. March 15, 2021. http://content.aia.org/sites/default/files/2020-03/ADR-Guide-final_0.pdf.
 Local Government Commission (LGC). The Move to Modular Housing: Cutting Costs to Advance Affordable Housing. Blog.March 15, 2021. https://www.lgc.org/newsletter/the-move-to-modular-housing-cutting-costs-to-advance-affordable-housing.