SF officials deem skyscraper safe after storms pop Downtown windows

To catch a falling shard has become a catch phrase in San Francisco after storm-driven winds blew out windows and cracked others atop skyscrapers Downtown.

Now city officials are scrambling to reassure the public that they are safe to walk through Downtown, while building inspectors consider changing building codes, the San Francisco Chronicle and San Francisco Business Times reported.

Last week, fierce winds popped a window from the 43rd floor of the Bank of America Tower at 555 California Street, sending a shower of glass down to the street below and triggering a shelter-in-place order. 

This week’s storm sent 78 mph winds whipping through Downtown, causing windows to crack along 20 floors of a Salesforce office building and battering three other glass-clad high-rises.

Board of Supervisors President Aaron Peskin, whose district includes one of the storm-lashed buildings, said he’s prepared to “move heaven and earth” to make sure that every tower in San Francisco is comprehensively inspected by a qualified engineer. 

“These are not one-offs, but part of a pattern that is likely to be the new normal as our weather systems change,” Peskin told the Chronicle, using an expletive to emphasize his fear for pedestrians walking downtown. 

Peskin called for a hearing to address the safety of windows in high-rises, and he is reviewing parts of the building code that he says are in dire need of reform.

When crews from the Department of Building Inspection assessed the storm’s toll, they logged a broken window on the 49th floor of the 58-story Millennium Tower at 301 Mission Street.

They found another between the 13th and 14th floors of a 36-story office building at 50 California Street, and another on the fifth floor of a 15-story apartment building at 1400 Mission Street.

But the 30-story Salesforce East office building at 350 Mission Street bore the biggest scars, with windows popping or splintering on every floor from 11 to 30, department spokesperson Patrick Hannan said. 

All four high-rises received notices of violation from the city requiring building managers to secure the broken windows, replace the glass and provide safety evaluations of all the windows in the building by a licensed engineer or architect within two weeks, according to the Chronicle.

The Department of Building Inspection will consider making updates to city codes following the window breakage, the Business Times reported.

Under the current code, windows are designed to withstand winds up to 90 mph — up from a 2009-era standard of 70 mph. The industry standard targets a probability of not more than eight of 1,000 windows failing when subjected to those winds.

“It’s definitely something we’ll be looking at,” Hannan told the Business Times. “We are also discussing the best way to proactively ensure high-rise windows remain safe and stable. 

“We have other programs for seismic safety, accessibility and facades — we haven’t settled on one solution, but are in discussions about what would make sense.”

— Dana Bartholomew