This article appeared in the summer issue of Urban Land on page 56.

When it comes to designing Mission Rock, a $1 billion, 28-acre (11 ha) mixed-use project south of AT&T Park in San Francisco that is scheduled for completion in 2025, architects already are trying to plan for a time when many of the cars on city streets will not have humans at the wheel.

They are envisioning an environment in which fleets of electric-powered autonomous vehicles will function as ride-sharing services do today, except that the machines will never need to take a break, except to charge their batteries. “Lyft and Uber are the avatars for autonomous vehicles,” explains Gerry Tierney, an associate principal at Perkins+Will, the lead architecture firm for the project. “The way we use them is the way that we’ll use an AV.”

For that reason, Tierney says, “none of the buildings are required to have on-site parking.” Instead, the guiding concern is that each structure will have adequate curb space to handle the passengers being picked up and dropped off, plus the surge in e-commerce packages that is expected as robotic trucks make deliveries cheaper.

But that future has not arrived quite yet. To deal with today’s parking needs, Perkins+Will’s plans also include a central parking garage to fill the current need for spaces—a garage that eventually can be disassembled and replaced with a structure one-tenth its size, so that the rest of the space can be converted to other, more valuable uses. “Think of it as a form of land banking,” Tierney says.

Above and below: ULI members attending the 2018 ULI Spring Meeting in Detroit take a ride in a self-driving microtransit vehicle from May Mobility.

Across the United States and around the world, the designers of tomorrow’s built environment face a similar challenge. With automaker Ford planning to market a commercial autonomous vehicle by 2021—along with engineers toiling away at other automakers, including BMW and Tesla, among others—the rise of robotic driving is expected to transform cities. Fleets of networked smart vehicles will move increasing numbers of people and goods—and dramatically reduce the need for parking garages and lots. At the same time, autonomous vehicles may compel architecture and development to evolve, by altering buildings’ relationship to the street and the patterns of how people exit and enter places. And even as some types of structures—such as parking garages and filling stations—become obsolete, there may be a need for new types of structures, such as nesting facilities to handle passenger pickup and drop-off. Buildings and electric driverless cars may also develop a symbiotic relationship in tomorrow’s smart grids, with buildings’ exteriors tapped as solar energy sources to keep autonomous fleets charged and rolling.

But with most experts predicting a gradual shift from human to robotic driving over several decades, developers and architects face the difficult task of creating projects that will satisfy today’s needs, while future-proofing them so that they will not become obsolete during their expected life span.

“If you’re planning to put up a building and keep it for the next 25 to 50 years, you need to think about how you’re going to deal with this,” Tierney says. “There’s no kicking the can down the road.”

Repurposing Parking

Click to zoom.

When on-demand autonomous vehicle fleets take the place of cars driven by commuters, car ownership is expected to decline. The need for parking—which accounts for 15 to 30 percent of urban land area—could drop by 50 percent over the next 30 years, according to The Transportation Revolution: The Impact of Ride-Hailing and Driverless Vehicles on Real Estate, a 2017 report by ULI and research and advisory firm Green Street Advisors.

Over the long term, the shift could create an opportunity to remake the built environment.

“A car is used only 5 percent of the time, so there are all these cars parked on city streets and in lots and parking structures,” explains Andy Cohen, co–chief executive of global design firm Gensler. “It’s really a real estate play. With autonomous vehicles, we can take back all of this prime real estate in our cities and convert it into green space, cafés, whatever you want. We did a study on this, and there are 500 million parking stalls in the U.S., and 5 to 6 billion in the world. This is an unbelievable opportunity.”

But the prospect of such a transition creates a short-term dilemma. How do architects design to fill today’s parking needs, knowing that demand may be drastically reduced within a project’s life cycle?

One way is to design parking so the space can be repurposed easily for other uses. “We’re telling clients now, if you’re building parking, definitely build above grade, so you can do adaptive reuse,” says Cohen. Gensler designed a headquarters in downtown Cincinnati for a data analytics firm named 84.51° that included three levels of parking that could be converted into office space, with a facade that matches the rest of the building.

Juan M. Villafane, an associate principal at Krueck + Sexton in Chicago, says his firm recently revamped its 2011 design of a garage structure for a high-rise office project that had been put on hold. The original parking podium had a split-level configuration with large central ramps and sloped floors. “That space would always be a garage,” he explains. “There’s no way to repurpose it.” The new design, in contrast, has flat floor plates and smaller ramps on the exterior.

Designing a convertible garage structure means dealing with other complex issues as well, according to Villafane. It is necessary to include higher ceilings for human comfort and to allow for the inclusion of mechanical systems such as ducts and conduits. To be usable as office space, a structure needs to be designed to handle heavier loads than a garage would need to support. Stairs and elevators may need to be in different locations than in a garage, since they will be used differently after the conversion.

At Houston-based design studio UltraBarrio, architects Marcus Martinez and Amna Ansari have created an ingenious concept for a parking structure that could evolve over time as needs change. Its floors would contain open areas where autonomous vehicles could enter and exit quickly from the street to drop off or pick up passengers, as well as other longer-term areas where vehicles could park themselves in dense packs while charging their batteries from solar panels on the building’s roof. If the need for parking were to vanish, the structure could be converted into vertical space for retail, residences, or offices, with the exterior ramps taken down to create green space around the building.

One downside of convertible buildings is that they would be more expensive to construct than conventional garages. But Martinez looks at the issue differently. “You’re getting two buildings for the price of one, with less waste,” he says. “Instead of making a ten-year building that you’ll have to take apart, you have a 50-year-building. There’s a higher initial cost, but it’s far more sustainable.”

Developers and architects also will have to work with cities to update zoning regulations that impose parking requirements, which are just starting to catch up to the shift to ride services. Amina Hassen of WXY, a New York City–based architecture, urban design, and planning firm, cites the example of New Rochelle, New York, which has implemented parking rules in facilities with 50 or more spaces that allow developers to substitute one car-share space for three conventional parking spaces.

Solving Curbside Congestion

The rapid growth of ride services such as Uber and Lyft already is creating logjams in front of buildings. Experts say the transition to autonomous vehicles—which would lower the cost of rides by eliminating the expense of drivers—is likely to intensify that problem. Add to that the trend of companies fitting more workers into the same floor space in buildings and ever-increasing e-commerce deliveries, and there is the potential for chaos, unless designers find a solution.

“Curb space is going to be a very scarce commodity,” predicts Randall K. Rowe, past ULI global chairman and founder of Green Courte Partners, a Chicago-based private equity real estate investment firm.

A rendering of what a New York City street might look like with autonomous shared vehicles. More space could be dedicated to pedestrian and bicycle use and to greenery. (KPF)

One solution for getting loading and unloading autonomous vehicles off the street, Rowe says, would be for fleets to build and operate staging facilities. “There could be a Ford staging facility in the middle of downtown Chicago,” he explains. “If you’re a subscriber, you would walk two blocks over to there and get into the type of car you ordered. It would be almost like a cab line at an airport.” He also envisions such facilities being built next to sports arenas, where hordes of fans using ride-sharing services already are making it difficult for patrons who pay premium prices for close-in parking to get out of those prime spots.

Others would design future office buildings and apartment towers to handle the increased traffic, adding drop-off space in the setback or even inside the building itself. Walter Hughes, vice president and design director for Dallas-based Humphreys & Partners Architects, envisions buildings relying more upon multiple entrances, each with its own hotel-like drop-off area, to reduce overcrowding at the front curb. Gensler’s Cohen thinks that building owners could even make up some of their lost parking revenue by charging ride services or passengers for VIP access to the most convenient drop-off areas.

“You can see that whole zone as an opportunity,” says Jeffrey Shumaker, director of urban planning and design at architecture firm Kohn Pedersen Fox Associates (KPF) in New York City. With autonomous vehicles’ technology for avoiding collisions, he even envisions doing away with curbs altogether, and allowing vehicles and pedestrians to mix in a shared space.

A KPF design for a master-plan project in Shenzhen, China, would separate legacy human-driven vehicles at street level and put autonomous vehicles and pedestrians on an elevated route, which might resemble New York City’s High Line park and trail—“the High Line meets the transportation system,” as Shumaker puts it. That way, autonomous vehicles “would drive more efficiently and not be interrupted. You could have drop-offs at each building location at that upper level.” Pedestrians also would have their own walking path, separated from the autonomous vehicles, on the elevated route.

“Much like the original High Line structure, which was built to create a safer and more efficient transportation system for trains, this new elevated structure could have a similar outcome for AVs,” Shumaker explains.

KPF’s design for a master-plan project in Shenzhen, China, incorporates green space throughout the project, replacing space that would have been needed by conventional vehicles. (KPF)

Buildings’ Relationship to the Street

Quiet, electric-powered autonomous vehicles also will influence urban architecture by eliminating exhaust fumes and the ambient din of traffic. “What will change is that the hostility of the street, borne by noisy, smelly automobiles, is going to go away,” says Craig Lewis, a Charlotte, North Carolina–based principal for design firm Stantec. As a result, he says, housing can be built along corridors that previously would have been undesirable locations, and buildings no longer need as much setback.

That also could increase the importance of the ground floor, which many architects expect will increasingly be open and connected to the street. Charles C. Bohl, an associate professor at the University of Miami’s School of Architecture, expects to see more buildings in the style of Miami’s Brickell City Centre, where an open arcade is cooled by a climate ribbon, an undulating canopy that is designed to allow in some natural light while providing shade and cooling. He envisions a return to “the traditional, almost pre-automobile environment at the ground floor.”

“We’ll see more cafés, restaurants, shops, greengrocers putting fruit and vegetables out there,” says Perkins+Will’s Tierney. “Commerce will be spilling out into the street. It’ll resemble a market town from 150 or 200 years ago.”

There will be more space for those activities, since autonomous vehicles—with their ability to communicate with one another and navigate more efficiently—will be able to maneuver in narrower lanes. Many envision using that as green space, with charging infrastructure for vehicles and bike rental stands integrated into the landscaping. “This is a chance to recast all our cities that have been about cars, and make them about people,” Cohen says.

Buildings and vehicles also may develop an increasingly symbiotic relationship, since buildings’ exteriors could be outfitted to collect solar energy needed to charge the vehicles. “The idea of a dynamic envelope around a building is very exciting,” says John Eddy, infrastructure practice leader at global architecture and engineering firm Arup.

Fleets of electric-powered autonomous vehicles will make some existing buildings obsolete. In addition to parking garages, “we have this ability to really take back spaces in our cities that are repair shops, car washes, gas stations,” says Cohen. “There are 125,000 gas stations in the U.S. We can gain all of those properties back.” But they also will create a need for new building types, such as centralized maintenance facilities and centers to manage the fleets and analyze the vast amounts of operational data they will generate.

Looking further into the future, there is the possibility of integrating autonomous vehicle fleets on the ground with flying vehicles of the sort that Uber is trying to develop, which initially would be operated by human pilots. As part of a design competition staged by Uber Elevate, Dallas-based design firm Corgan envisioned modular sky ports that could be placed in various locations around a city. The basic structure, which could be built atop an existing parking garage or building rooftop, would be able to handle as many as 90 vertical landings and the same number of takeoffs per hour. From street level, passengers would arrive via autonomous vehicles, bicycles, or other means of ground transportation, and go up to a station level where the flights would take off.

The sky-port space could serve other purposes as well. “In our concept, it’s a big community space,” explained Corgan principal John Trupiano. “It has parks and stages, and it could host a farmers market or a concert. That’s the piece that we see connecting communities to the stations.”

KPF’s Shenzhen plan would separate legacy human-driven vehicles at street level and put autonomous vehicles and pedestrians on an elevated route. (KPF)

Location, Location . . . Never Mind

Whether on the ground or in the air, autonomous vehicles also may affect the built environment by making it so easy for people to move around that location—long one of the most important factors in the real estate sector—may not be quite as important as the building itself.

“Because transportation is easier and I can be anywhere, the question becomes: where will I choose to spend my time?” says Nico Larco, an associate professor of architecture at the University of Oregon, and codirector of that school’s Sustainable Cities Initiative. “In the past, I might have gone to that strip mall down the street because it was the closest place for me to buy something.

But that might change in the AV world. What might become more important is the quality, the vitality of a place, the buzz, the synergy. If I need some commodity, I can buy things from Amazon. I’m going out for the experience.

“Architecture and urban design used to be the containers of commerce,” Larco continues. “They might very well become the generators of it. And absolutely, that puts pressure on architects to design more interesting buildings—and for developers to pay to build them.”