Roche's Genentech cleared for massive headquarters expansion that will add up to 4.3M square feet

South San Francisco has approved a master plan that allows Roche's Genentech to almost double its building space to about 9 million square feet at its headquarters. (Roche)

More than 40 years since setting up shop in a rented warehouse as the modern world’s first biotech company, Roche’s Genentech is now up for a major expansion at its South San Francisco home in California.

Tuesday, the local city council approved Genentech’s expansion proposal, which aims to almost double its headquarters’ building space to 9 million square feet from the current 4.7 million square feet.

That extra buildout, all within the boundary of its existing 207-acre campus, allows the Roche unit to add as many as 12,550 employees at the HQ on top of the 10,000 or so who are there right now, according to the master plan (PDF).

Of course, the development won’t happen overnight. The company describes it as a “vision” or “guideline” for potential future growth, rather than “an indication of immediate changes or expansion to the existing campus.”

In fact, the blueprint covers 15 years, and the new hires—if they eventually happen—will span “the next several decades,” the company said in the master plan. Plus, construction of any individual new buildings, details for which are expected over the next 20 years or so, will require separate approvals.

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The additional building space could be used for a variety of functions including R&D, manufacturing, infrastructure, office, on-campus amenities and employee support, according to Genentech.

Through the level-up, Genentech said it intends to maintain its current ratio of lab-to-office space; they now each make up roughly one-third of the total building space. As for on-campus manufacturing, which now occupies a little less than 1.3 million square feet, the company expects it “to be retained but not substantially expanded,” with possibly some potential redesign or reconfiguration. That being said, the master plan “intentionally permits” some flexibility in how the company allocates space to each function.

As part of the expansion, Genentech expects to shell out more than $250 million in city fees and investment in South San Francisco’s transportation, housing and community programs.

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Genentech settled in South San Francisco in 1978. Thanks to the biotech industry, the city prospered even after its steel industry died. The Genentech site, where Bethlehem Steel used to stand, has already added about 2 million square feet of building space from the previous 2007 master plan to the current 4.7 million square feet.

Aside from the Genentech site, Roche recently unveiled a plan to invest $500 million over five years to establish a global technical operations center at its Canadian pharma headquarters in Mississauga, Ontario.