The Pacific Bell tower in San Francisco, the high-rise headquarters of the phone company through eight decades and several name changes, was a monument to copper.
When the 26-story skyscraper was built, Pac Bell’s business was connecting people through a technology that many were starting to use for the first time.
Phones were catching on all over the West Coast, particularly in San Francisco, and Pac Bell was buying up small carriers as part of the budding nationwide Bell System. The communications arteries that fed this growing trend were thick trunks of copper wires, each with a capacity that seems positively petite by today’s standards.
Stockbridge Capital Group and developer Wilson Meany acquired the building and an adjacent garage from AT&T in 2007 for $117 million. A plan to convert it to condominiums fell through, but soon San Francisco’s commercial real estate market boomed and the strategy shifted to office space. The graceful Art Deco tower, designed by famed architects James Rupert Miller and Timothy Pflueger, will house up-to-date office space with historic features such as exposed brick walls and opening windows.
San Francisco-based Yelp has leased about half of the building as its future headquarters and, as of last week, 70 percent of the total space is leased, according to Wilson Meany. Two restaurants are already lined up for the ground floor, and the building should be fully occupied and functioning by next April, said Wilson Meany project manager Josh Callahan.
To bring the building up to date, Wilson Meany gutted it, ripping out interior walls that were covered with generations of office decor layered on top of each other, Callahan said. The building had been office space for about 2,000 rank-and-file PacBell workers and a few high-ranking executives, but it wasn’t a switching hub.
Yet in the basement, Wilson Meany found several times the network capacity of a typical office tower. There were 8,000 pairs of copper wire and six or seven fiber cables coming in from the street, compared with about 1,500 copper lines and one fiber cable in most buildings, said Keith Burrows, executive vice president of Decker Electric, the project’s electrical subcontractor.
Most of that wiring is no longer needed. With traditional copper lines, each phone needed its own pair of wires. Designed just for voice calls, they topped out at 56Kbps (bits per second). Later, T-1 lines (1.5Mbps) let companies link 24 phones to the outside world over just two pairs. But Wilson Meany expects most of the phones at 140 New Montgomery to use VoIP (Voice over Internet Protocol), which sends calls over an ethernet LAN and then onto fiber. One fiber cable, which can bundle together hundreds of strands of fiber, can carry almost unlimited amounts of voice and data traffic. To meet traditional phone needs, Wilson Meany will keep one copper trunk with 1,800 to 2,400 pairs and give each floor enough wire for 24 individual phone lines.
The developer is using one fiber cable for its own use and will allow tenants to deploy their own cables. There are eight conduits up through the building, each four inches in diameter, for just this purpose.
“The biggest thing is to get the pathways in. That’s what we’ve done. That gives everybody the ability to get what they want in the future,” Burrows said. Even Yelp, which might have as many as 1,000 employees in the building, would only need one fiber cable to the outside world for all its voice and data traffic, he said. “To get an amazing fiber service, it’s one fiber the size of your finger.”
Tenants can bring that fiber to a wiring closet on each floor and connect it to an ethernet LAN with wiring laid in trays hung from the exposed cement ceilings. That’s typical today, but it’s a departure from the wiring system that Pacific Bell installed when it built the building.
PacBell ran its phone lines down pipes in the concrete floor, pulling it up to employees’ desk phones through holes in the floor spaced every few feet. That system was on the cutting edge in 1925 and became common in later decades, but now internal wiring is typically laid above a dropped ceiling or in trays hung below an exposed ceiling, which 140 New Montgomery’s tenants are expected to do.
Ensuring good wireless signals in a building built at the dawn of the radio age may be more of a challenge. The exterior walls of 140 New Montgomery are concrete, with brick filler on the inside, originally covered but now exposed for a historic look. Neither material is very friendly to wireless networks, and in retrofitting the structure for seismic safety, Wilson Meany added more concrete and 2 million pounds of reinforcing bars in the core of the building.
The developer is still evaluating how Wi-Fi will perform in that setting. It will provide Wi-Fi on the first floor and in a private courtyard, but any additional networks will be the tenants’ responsibility. Repeaters should allow them to cover the L-shaped floorplans, Callahan said. With the phone company’s original hollow-tile interior walls gone, any new office walls can be built with plasterboard, which doesn’t block signals as much.
Relying on conventional macro cells outside may work for a while, but Wilson Meany plans to have some form of cellular repeater or distributed antenna system installed by either an existing carrier or a neutral host provider, he said.
One place where the landmark building will scrape the cutting edge of technology is in the building management network. Elevator controls, building security, mechanical controls, per-floor power meters and HVAC (heating, ventilation and air conditioning) systems will all be linked over an ethernet LAN running up the central riser of the building, Callahan said.
That linkage will allow for better overall management, including remote Web-based management, and for automating some tasks. For example, when an employee arrives and flashes an identity badge, he or she can be directed to an elevator that will go right to the correct floor.
But in most ways, the point of 140 New Montgomery is not to break new ground as much as to put current technology in a massive Art Deco jewel box.
“It’s taking a building of this architectural quality and size and bringing it up to those same standards that a new building would have,” Callahan said.
The developers, architects and subcontractors want to let tenants create future technologies in a space that says something about the past, and maybe a bit about an earlier communications boom.
Updated on Monday, May 6, with a video report.