The site of a former gravel yard, a triangular plot in San Francisco’s design district is now home to the first multi-storey mass timber building in California. Designed by Perkins&Will with DCI Engineers, the newly completed 1 De Haro is both a feat of material innovation and an intriguing mix of commercial offices and light industrial uses. From afar, the five-floor structure is an aesthetic cousin to the “one-plus-five” — or “five over one” — stick-frame residential buildings that have become a nearly ubiquitous urban presence across the United States. But while 1 De Haro shares a typological kinship with its light-frame “stick” apartment block counterparts, Perkins&Will’s design harnesses cross-laminated timber (CLT) and glulam to create a mixed-use building that celebrates the presence of structural wood.

Atop a one-storey concrete base (which houses a light manufacturing facility), the 12,500-square-metre building’s exposed timber skeleton is prominently visible behind four storeys of sleek glass curtainwall.

Inside, wood takes centre stage, with the blonde surfaces lending the simple lobby and the otherwise spare offices a feeling of warmth. A unifying theme throughout the minimal yet airy commercial spaces, timber surfaces frame the upper storey offices — even the custom-designed sunshades that help cool the building and reduce energy costs are made of wood.

Designed to evoke a jewelry box, the wood interior glimmers in the evening light. According to Perkins&Will design director Peter Pfau, the mass timber design creates a visual and spatial signature for the building. “You don’t have to spend money covering up the ugly construction,” he notes, “instead you just celebrate the beauty of the wood and detailed craftsmanship.”

But the choice of construction method is much more than aesthetic: Made renewably, CLT and glulam offer a relatively low-carbon alternative to the steel and (especially) concrete structures more commonly used in commercial design.

The relatively lightweight wood skeleton also meant that fewer piles were required for the building’s foundation — a particularly acute benefit given the site’s soft soils. What’s more, the wood itself arrived by rail, significantly reducing the carbon costs of material transportation. Delivered from Quebec manufacturer Nordic, the CLT and glulam structure traveled across the continent to become the first building of this kind in California.