Right-sizing is setting a parking supply, and the type of facility that provides it, from measured or modeled demand rather than from a legacy ratio, a code minimum or a negotiated number.
- Inputs
- Demand counts or a demand model, pricing, shared use, transit and TDM
- Example
- Foothill Gold Line: 3,570 planned spaces at five stations reduced to 1,979
- Key fact
- Right-sizing is not cutting: it means building what demand requires and keeping options open
Parking supply is often set by habit: a ratio from an older project, a zoning minimum, or a number negotiated in a public meeting. Right-sizing replaces that with evidence. It asks how many people will actually park, at what price, at what time of day, and whether some of them could share spaces, arrive another way, or use capacity that already exists nearby.
How it is done
- Count or model demand by hour and day, including the peak that matters, not just the average.
- Put price in the model, because a daily charge changes how many people drive.
- Credit shared parking between uses that peak at different times.
- Account for transit, walking, cycling and TDM programs.
- Right-size the facility type as well as the count: a surface lot is cheaper to build and run, and easier to convert later, than a structure.
An office, a restaurant and apartments sit on the same site. Their parking peaks at different times of day. Turn uses on and off to see how many spaces one shared garage needs compared with separate lots.
Sized separately for their own peaks, a 300-car office, a 120-car restaurant and 200-car apartments need 620 spaces. Because the office peaks at midday, the restaurant in the evening and the apartments overnight, one shared garage needs about 470 spaces, 150 fewer, worth about $4.5 million in construction at $30,000 a space.
Illustrative weekday hourly profiles in the spirit of the ULI Shared Parking model; $30,000 a structured space. A real shared parking study uses local data, weekend and seasonal peaks, and a safety margin.
The Foothill example
On LA Metro’s Foothill Gold Line extension, a funding gap prompted the project team to test the approved parking program against Metro’s demand forecast. The supplemental environmental review, with a $3 daily charge in the model, concluded the five Los Angeles County stations needed 1,979 spaces rather than 3,570, and four planned structures became surface lots. By the project team’s estimate the change avoided more than $100 million, and the segment opened on time and on budget in 2025.
The Parkonomics view
The purpose of parking is access to a place, not storage for as many cars as possible. Expect resistance from neighbors worried about spillover, and answer it with a transparent model, a pricing strategy and a public process rather than a bigger number.
Related terms: Parking Demand Analysis, Shared Parking, Transportation Demand Management, Parking Ratios, Parking Minimums, Park-and-Ride, Spillover Parking
Further reading: Designed to Park, or Designed to Impress?, The Evolution of U.S. Parking Structures in 2026