Silicon Valley is starting to bring workers back to the office

San Francisco(CNN Business) After years of building huge modern offices and a work culture that many industries have emulated, Silicon Valley was among the first to shutter those offices and go fully remote when the coronavirus pandemic began.

Now, many of the tech industry's biggest companies are slowly making plans to bring workers back, offering a potential road map in the process for what office work looks like in year two of the pandemic.

On Monday, Uber (UBER) opened the doors of its new campus in San Francisco's Mission Bay, which it finished constructing during the pandemic. The office initially opened at 20% capacity, with employees allowed to return on a voluntary basis, and around 100 employees came in on Monday and Tuesday according to Uber spokesperson Lois Van Der Laan. The company currently has around 3,500 employees in the Bay Area.

Employees who choose to come back to the office are required to have a virtual "boarding pass" which they can get by signing an acknowledgment form detailing Covid-19 precautions, taking a daily health screening at home and reserving a spot in the office so Uber can control occupancy, she added. The majority of Uber workers can continue working from home until at least September 13.

Facebook (FB) is also planning to allow some workers back into its Silicon Valley offices in the next few weeks. The company will reopen certain Bay Area offices at 10% capacity starting in May, Facebook spokesperson Chloe Meyere told CNN Business.

"The health and safety of our employees and neighbors in the community is our top priority and we're taking a measured approach to reopening offices," Meyere said in a statement, adding that aside from physical distancing and mask requirements, Facebook will also mandate weekly coronavirus tests wherever possible for workers coming in.

Facebook employees also have the option of not returning to the office at all, with CEO Mark Zuckerberg predicting earlier this year that half of Facebook's workforce could be remote within the next decade. For those who need to come into the office, the company will allow them to work from home until a month after their nearest office opens at 50% capacity. Facebook says its largest offices likely won't allow 50% capacity until at least September 7 this year.

Twitter said it has not yet set a date for when employees can return to the office, but when it does it will only allow 20% capacity to start. The social media company told employees early on in the pandemic that they could work remotely "forever" if they so choose, but anticipates that a majority of workers will opt for a mixed or hybrid model once offices reopen, where they come in sometimes and work from home otherwise.

Google confirmed on Wednesday that it will start bringing US employees back to the office in April on a voluntary basis. Googlers will not have to return to the office until at least September, the company's previously stated deadline, after which Google has said it will start testing a flexible workweek where they come in only for three days.

Apple (AAPL), which did not respond to a request for comment, reportedly started bringing employees back to its headquarters as early as May last year.

Outside of Silicon Valley, Microsoft (MSFT) began bringing some workers back to its headquarters and nearby offices in Redmond, Washington on Monday, in what it described as a "hybrid workplace" model.

The range of scenarios big tech companies are sifting through highlights just how much uncertainty remains around returning to the office, even as vaccinations pick up pace across the United States and around the world. The gradual reopening may also be the clearest test yet for the resiliency of the Bay Area market. Many Silicon Valley workers, taking advantage of flexible remote work policies, have decamped to other cities including Austin, Miami, Nashville and Denver. Several major companies, with Oracle and Hewlett-Packard Enterprises among the notable names, have also relocated.

"Every person at every company presents a unique and different situation," David Bergeron, president of tech-focused real estate firm T3 Advisors, told CNN Business. Bergeron says the appeal of remote work for companies is that they can attract a broader talent pool than their competitors, but it'll be a balancing act.

"The risk is if you try and fail at 'going remote' you could have an incredibly long and difficult road back earning the trust of current and future employees," he added.

But calling the end of Silicon Valley's dominance may be premature, and only time will tell how much of the exodus is permanent, particularly when the region's biggest firms fully reopen.

"The things that made Silicon Valley special are not going anywhere," Jim Breyer, one of the area's most prominent venture capitalists who recently moved to Austin, wrote in an op-ed for CNN Business earlier this month. "The Bay Area will continue to be a global hub of innovation that attracts courageous entrepreneurs, benefits from world-class institutions and nurtures talent from leading tech companies — even as Austin offers a remarkable new frontier of opportunity," he added.

San Jose, one of Silicon Valley's biggest cities and home to companies such as Cisco, Adobe and PayPal, ranked top among 50 US cities for office development opportunities in a report last month by the real estate firm CBRE, in part because of a "strong demand" for office space and favorable construction costs.

Colliers, another real estate firm, said in a subsequent report that Silicon Valley "proved to be more resilient than other technology markets" during the pandemic, largely thanks to the "wealth of established tech companies," including Google, Facebook and Apple. The region accounted for more than 40% of venture capital spending last year, according to the firm.

"The fundamentals of the Silicon Valley market remain strong and the market is well positioned to rebound from the pandemic more quickly than other areas, due to its high concentration of large technology companies and a healthy start-up community," Lena Tutko, senior research manager at Colliers Silicon Valley, said in a statement. "Silicon Valley remains the epicenter of innovation."