Commercial
Verdant LA mixed-use building exposes mass timber for a natural touch
Could Los Angeles become the next big city to embrace mass timber construction?
Portland-based LEVER Architecture’s new 843 North Spring Street is the one of the first large uses of cross-laminated timber in a contemporary office building in the city. Located on the eastern edge of Los Angeles’ Chinatown, the five-story-tall, 145,000-square-feet structure is both old and new, incorporating an existing two-story concrete parking garage as its base.
The mixed-use project includes office, retail, a garden courtyard, an amenity deck, and below-grade parking. Located adjacent to the elevated Chinatown station of the Los Angeles Metro Rail, the architects drew on the urban forms of the tight-knit neighborhood and Chinese culture. “There are these amazing alleys that connect streets,” LEVER Architecture Principal and Founder Thomas Robinson says. The building echoes those alleys with a variety of passageways and an open-air atrium based on the model of the Chinese courtyard house.
843 N Spring Street
The building is configured in two parallel bars: A broad open stair at the north end of the building on College Street welcomes people to the building’s central garden courtyard, which provides landscaped areas on every floor. Exterior decks cantilever from the perimeter of the north and south ends of the structure, expanding the office floors to the outdoors, where workers can take advantage of LA’s temperate climate. LEVER worked with James Corner Field Operations in developing the landscape design that weaves garden spaces throughout each floor of the office block. “That urban generosity and connection to landscape and connection to the urban fabric of Chinatown was something that was really important to the design,” Robinson says.
The project is technically a renovation that places the new glass, steel, and mass timber structure atop a 1980s-era retail warehouse and parking garage. The hybrid solution keeps each material exposed to view. “The hybrid gives you the opportunity to take advantage of the structural characteristics of each material and then combine them in ways that make each of them better,” Robinson says.
843 N Spring Street
843 N Spring Street
Lightweight mass timber allows for adaptive reuse
The new structural steel columns and beams maintain the original 30-feet-by-30-feet grid throughout the new four-story addition. The floors are composed of 3- and 5-ply CLT panels with concrete topping slab. The underside of the panels remains exposed in both interior and exterior locations, creating a distinctive fifth elevation that defines the interiors and is quite noticeable from the surrounding streets. “We wanted to really feature the expression of what CLT and the wide flanges that support it can do together,” Robinson says.
The exposed CLT panels are a hybrid of Douglas fir and spruce-pine-fir. “The CLT allowed us to build atop the building’s existing foundations with a lighter structure that meant less reinforcing of the existing concrete garage—instead of demolishing and completely rebuilding the structure—a significant savings in embodied carbon,” Robinson says. In addition to the savings from that adaptive reuse, the use of mass timber itself led to an estimated reduction of 1,357 metric tons of carbon compared to traditional building methods.
843 N Spring Street
843 N Spring Street
Although mass timber is uncommon as an exposed material on building exteriors, it has the potential to create a unique, eye-catching aesthetic, especially in a climate where occupants can spend time outdoors year-round. “I’m not somebody who thinks that you should put a lot of exposed timber on the outside of [a] building,” Robinson says, citing his concern over how the material will wear. “But selectively doing it in a way that it’s expressive and makes sense is something that we’re very interested in exploring.”
“Timber is a natural material that people connect with in the same way that people connect to landscape and to outdoor space,” he says. “It allows people to feel really comfortable being at work.” Ultimately, 843 North Spring Street points to both a new and an old way of building in the City of Angels. “There are tons of [existing] timber buildings in LA,” Robinson says. “It’s just not something that people are using to build new buildings.”
With 843 North Spring Street, LEVER Architecture is doing what they can to change that.
