California Updates Building Codes to Advance Housing Creation and Climate Goals

AIA California-led initiative simplifies adaptive reuse of empty office and retail structures for new housing.

(Sacramento, California) June 30, 2023—In an action that simultaneously addresses the climate emergency and California’s housing crisis, the California Building Standards Commission voted this week to ease barriers to the safe conversion of underused existing commercial buildings.

The adaptive reuse of retail and office structures (vacated due to market changes such as work-from-home and online shopping) can reduce the carbon footprint of construction, while also helping revitalize our communities. The potential is enormous, as highlighted in a recent RAND Corporation report that found some 2300 underutilized properties in Los Angeles county alone that could product 72,000 to 113,000 housing units.

In terms of sustainability, renovation and reuse projects typically save between 50 and 75 percent of the embodied carbon emissions compared to constructing a new building, according to Larry Strain, FAIA, a sustainability expert.

This major code advancement was initiated by the American Institute of Architects California in 2019.  What followed was literally years of behind the scene work involving many stakeholders.

“This action is a real catalyst for change that will push the industry forward in rapidly addressing the growing climate emergency,” said William Leddy, FAIA, AIA California Vice President of Climate Action, and partner in a San Francisco-based architectural firm that consistently designs sustainably high-performing projects.

“The most sustainable buildings are the ones that are already built. Prioritizing the reuse of existing buildings not only accelerates the reduction of embodied carbon emissions from new construction, it ‘incentivizes’ the industry to address California’s severe housing crisis more quickly and efficiently, creating more sustainable and resilient communities,” Leddy continued.

Because many of the impacted buildings are situated in the urban core of cities across the state, their reuse as housing has a secondary impact: the revitalization of metropolitan centers.

Ahead-of-the-Curve Thinking Shapes the Future
AIA California began shaping the code landscape for existing buildings over four years ago, but code change is a long and rigorous process. The State Fire Marshall became a core partner in this effort, as they managed multiple technical working groups that went through code language line by line, with key issues being debated, discussed and fine-tuned.

“AIA California is committed to accelerating substantive changes that facilitate carbon reduction,” said AIA California President Scott Gaudineer, AIA. “As architects, experts, and citizens, we have no time to waste. We are grateful to the State Fire Marshall for being our partners in this initiative and to California Building Standards Commission for taking action which will lead to a better future for generations to come.” 

California Existing Building Code Put to Use
The change, amends the California Existing Building Code, and turns what many Californians might see as a mundane bureaucratic element into a powerful tool that expands California’s role as a climate leader and offers new hope to rehouse people in a state where a recent University of California San Francisco study found that nearly 50% of those without shelter are age fifty or older.

In its vote, the California Building Standards Commission altered California’s Title 24 Part 10 Existing Building Code (CEBC) by adding Chapters 6, 7, 8, 9, 10, 11 and 13 of the International Existing Building Code (IEBC) into the 2022 CEBC.

Michael Malinowski, FAIA championed this effort on behalf of AIA CA from the beginning, tapping his expertise as a practicing architect with extensive experience with commercial to housing conversion projects.  He is also familiar with the code process and the model codes, as an appointed member of the national ICC Existing Building Code Committee.

“The new California Existing Building Code will allow for greater flexibility in responding to the complexities of existing building reuse, harnessing the power of design thinking to respond to the complex challenges often found in existing buildings. AIA CA is working with the International Code Council (ICC) and other stakeholders like CALBO (California Building Officials association) to provide training and orientation to this new material,” Malinowski noted.

The international Existing Building Code provides three options, known as compliance paths, from which to choose: Prescriptive; Work Area; and Performance.  All three paths lead to safe, code-compliant buildings, but their differences allow design professionals significant latitude to find a code path best suited for a particular building challenge. The existing California code includes only the Prescriptive path effectively limiting potential for adaptive reuse.

The architectural profession stands ready to work with developers and all members of the design and construction industry to utilize these options to create new possibilities for communities, repurposing the many existing underutilized and obsolete commercial buildings in our urban centers, breathing new life into our urban cores with walkable, sustainable, and resilient design solutions.


Tibby Rothman
Director of Communications

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