California is the most expensive state to build affordable housing in part because the costs to build are high. Some builders are turning to modular, prefabricated housing as a way to speed up production and rethink the way we've traditionally built in the Bay Area.

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Reported by Molly Solomon and Erin Baldassari. Edited by Erika Kelly. Bay Curious is made by Katrina Schwartz, Suzie Racho, Rob Speight and Katie McMurran. Additional support from Erika Aguilar, Jessica Placzek, Kyana Moghadam, Paul Lancour, Carly Severn, Ethan Lindsey, Vinnee Tong and Don Clyde.