1 De Haro

San Francisco


Submitted By: DCI Engineers

Owner: SKS Partners, LLC

Lead Design Firm: Perkins+Will

General Contractor: Hathaway Dinwiddie

Civil Engineer: Luk & Associates

Structural Engineer: DCI Engineers

MEP Engineer: ACCO Engineered Systems

Architect: Perkins+Will

Mass Timber Supplier: Nordic Structures

The 135,000-sq-ft building marked several milestones—the first multi-story mass timber building in California, the first mass timber building in San Francisco and the longest single-span cantilever floorplates in North America. The use of lighter-weight building materials was well-suited to the triangular-shaped site’s soft soils and seismic characteristics. Timber construction also substantially reduced the number of piles required to anchor the foundation.

The building was designed to encourage new businesses in the neighborhood while retaining the site’s light industrial-use legacy. To qualify the development for light industrial use, the first floor was constructed out of concrete, which allowed for a greater mass timber floor area for the three upper levels. Computer-controlled sawing and finishing machines fabricated the seven-ply cross-laminated timber (CLT) panels to the millimeter, allowing for precise installation.

The panels’ attractiveness also helped the team provide a spacious interior despite the building’s zoning-imposed 58-ft height limit. While the first floor’s 20-ft-tall ceiling accommodated a mezzanine level, exposed CLT and notched glulam girders allowed 12.5-ft floor-to-floor heights. To dampen noise from solid surfaces, the CLT floor slabs were topped with concrete and an acoustic mat break.

Field erection required only two months—much faster than a traditional stick-framed process—and minimized construction activities in the neighborhood. A comprehensive training program in mass timber construction integrated into the contractor’s safety culture resulted in no recordable incidents or lost-time accidents over more than 202,000 worker hours on the job.