April 17, 2018

Much has been written about autonomous vehicles—also known as driverless vehicles—in terms of their safety benefits and their projected impact on transportation. It is anticipated that these robocars of the future will be available to the public by 2025, and within a decade will have reduced the need for parking in the U.S. by more than 61 billion square feet. Given such statistics, the effects of autonomous vehicles on urban and suburban development is also a hot topic, especially within the A/E industry. In today’s post, I take a closer look at the subject, along with design strategies that plan for this future decrease in parking demand.

It is anticipated that within the next 10 years, autonomous vehicles will have reduced the need for parking in the U.S. by more than 61 billion square feet.

Hedging Against the Megatrends

I personally feel that the potential change in mature metropolitan areas due to autonomous vehicles will not be as disruptive as it will be in smaller, evolving markets because developed mass transit has kept the need for parking relatively low. For many second-tier urban areas, tenants and their brokers are still asking for new space to bring high parking ratios. Moreover, a trend of added density combined with more mobile workers has pushed that ratio higher in recent years. Previously, a ratio of three parking spaces per 1,000 square feet in urban areas and approximately four spaces per 1,000 square feet in suburban areas was common. Today, tenants regularly seek four to five parking spaces per 1,000 square feet. This results in construction of space for parking that rivals the area for lease.

In Tier-II cities, the more extreme dedication of construction to support cars means a potentially enormous lost value in obsolete purpose-built space. The strategies currently being employed generally fall into a couple categories: garage geometry and parking technology. These strategies are aimed at hedging against the results of megatrends such as autonomous vehicles, and preserving the long-term value of real physical investments.

Garage Geometry

Increasing the levels of a parking structure floor-to-floor may carry some inherent cost, but this strategy has a major impact on how garage space can be repurposed. In fact, Nashville’s building code once encouraged this design approach. Another strategy involves strategically arranging the ramping in a parking garage so that flat areas can be converted into other uses in the future while still allowing the parking circulation to function. A garage can also be designed to allow upper levels, most likely contiguous with occupied space above, to be converted as needed.

Short of converting space, another approach is to push parking below grade where lower utilization will be less apparent in the future. This design strategy, however, results less in retained value and more in hiding lost function.

Increasing the levels of a parking structure floor-to-floor may carry some inherent cost, but this strategy has a major impact on how garage space can be repurposed.

Parking Technology

Lifts are becoming more common as a strategy in terms of increasing capacity while building less permanent structure. For example, when constructing tall floor-to-floor garages to support future conversion, these spaces can incorporate lifts to increase capacity in the near term, and be easily removed in the long term, to reduce capacity and ultimately allow total conversion of use.

Automated parking systems may not be far behind for some building types, though the maturity and price point of such systems may mean they are not as widely adopted as imagined.

Whether it involves garage geometry or parking technology, all of these strategies bring added cost in the near term. Some business models for development make it difficult to reconcile those near-term costs with the desire to extract a near-term profit. For those who plan to hold their investments longer, these issues should be of serious concern.

Moore is More

Slated for completion in 2020, the 214,00-square-foot Moore Building in Nashville’s Midtown/West End district is a good example of how GS&P designers are planning buildings for the future. The 15-story office tower comprises 9,000 square feet of retail on the first floor, followed by five floors of parking and eight floors of office space. We are currently exploring ideas that would allow the parking to be versatile beyond the garage’s useful life of simply serving as a storage bed for user-driven cars. That versatility also extends to the building’s offset core, which places the elevators, mechanical systems and restrooms to one side of the building as opposed to the center of the structure. This essentially redefines the conventional methodology of a typical office building, with the wide-open planning allowing for flexibility in terms of future interior tenant fit-ups.

The forthcoming Moore Building in Nashville's Midtown/West End District includes five floors of parking situated atop retail space on the first floor. GS&P designers are exploring ideas that would allow the parking to be versatile beyond the garage's useful life of simply serving as a storage bed for user-driven cars.

Realistic Expectations

Less demand for parking should not be viewed as a trend driver in and of itself, but rather the result of several other trends. We can more clearly see how automation and the advent of services like Uber and Lyft may impact the built environment. However, we cannot see quite as clearly other trends that may create the future utility of this space, which may be driven by factors such as a more mobile workforce, Airbnb properties, the need for housing equity and any number of undetermined influences.

Ultimately, we need to plan for a flexible future and not simply assume we know too much about what that future might be. The built environment is rife with assumptions about futures that did not come to pass.