Parking requirements aim to ensure that new residents have a dedicated place for their vehicles without creating negative spillover effects on public parking in the surrounding area. However, parking requirements increase the cost of developing housing by increasing the land area required, unless the development incurs the added expense of structured parking. Particularly in the development of multifamily housing in urban areas, structured or underground parking can cost anywhere from $25,000 to $65,000 per space, a significant cost factor for each unit of housing. In many cases, minimum parking requirements also go beyond what is strictly needed to ensure that residents have adequate parking, which may encourage higher rates of car ownership and driving, and increase congestion and pollution. In addition, there are circumstances where a one-size-fits-all parking requirement results in excess land dedicated to parking that might otherwise be used for housing.
Cities, towns and counties seeking to expand the supply of housing may wish to revisit their zoning code to determine whether current minimum parking requirements can be reduced in some or all parts of town or for certain development types. By reducing off-street parking, communities can lower development costs, potentially free up land for additional units, and reduce the cost of housing for residents. Alternatively, some cities establish parking maximums, rather than minimums, to discourage the creation of excess parking spaces.
In this section we review a number of the factors that should be addressed in developing and implementing reduced parking requirements.
Cities can structure parking requirements in a variety of ways. Some jurisdictions set requirements based on the dwelling unit type – for example, a single-family home may be required to have at least one off-street parking space, a duplex may be required to provide two spaces, and so on. For multifamily buildings, the number of required parking spaces is commonly linked to the total number of bedrooms (e.g., in a jurisdiction that requires 1.5 spaces per bedroom, a 20-unit building would need to provide 30 parking spaces). These minimums may be applied uniformly across the city or may vary based on the location of the housing, with lower parking requirements more common in areas close to transit stations or major bus lines. (See Alexandria, VA example below.) Neighborhoods designated for higher-density and/or mixed-use development with access to public transit may have relatively low per-unit parking requirements compared to areas with low-density single-family homes, on the assumption that residents who are able to access many destinations by public transit or on foot are less likely to own a car.
In addition to requirements related to building size and location, some communities establish parking standards based on the planned occupants of a building. These adjustments account for lower vehicle ownership rates among certain types of households, such as seniors and low-income households. Senior apartments, assisted-care units, and congregate care facilities are all likely to have lower parking demand than non-age-restricted developments of the same size. A zoning policy that doesn’t account for these differences would require an equal number of parking spaces per bedroom, and likely result in an oversupply of parking. New York City has eliminated off-street parking requirements for subsidized housing and senior housing located within a “transit zone” that covers parts of the city within one-half mile of the subway. Other considerations may include the amount of secured bicycle parking provided by the building and the availability of car-sharing vehicles.
Local jurisdictions can reduce the number of spaces required per unit (e.g., from 1.5 to 1.0 spaces per bedroom for multifamily dwellings) on a community-wide basis, in particular zoning districts or locations (e.g., within a quarter-mile of transit stations), for particular types of housing (e.g., age-restricted senior apartments), or based on some combination of these characteristics. Some cities eliminate parking space minimums altogether—most commonly in the downtown or central business district, but also near transit stations and college campuses.
Some communities not only have eliminated minimum parking requirements but have adopted parking maximums instead. Rather than stipulating a minimum number of spaces that must be provided, this approach places an upper limit on the number of parking spaces that may accompany a residential development. Replacing parking minimums with parking caps can help developers avoid having to over-supply parking just to comply with regulatory requirements (or avoid the process of securing a zoning variance that allows them to provide fewer spaces than required). Such caps can also help to discourage driving and encourage the use of public transit and walking.
When making revisions to parking requirements, communities should consider seeking feedback early in the process from a broad range of stakeholders, including transportation planners and engineers, representatives of the local transit authority, and for-profit and non-profit housing developers and managers. Additional analysis to determine actual vehicle ownership rates by income level, age of household head, and household size, as well as proximity to and availability of public transit and actual parking utilization rates may be helpful to inform policy development and ensure requirements reflect local circumstances. Whatever criteria are used to establish standards, zoning and planning staff should ensure that they are clearly defined in sufficient detail in order to avoid confusion or disagreements in interpretation.
Targeted reductions in parking requirements to promote affordability
Some communities also reduce parking requirements for individual developments, as an incentive to set aside a share of units for low- and moderate-income households.
Alexandria, VA has a complex set of off-street parking requirements that are tailored to the development type and part of town. Single-family detached homes and duplexes, rowhouses, and townhouses must have 2 parking spaces per unit. Multifamily buildings that are located within walking distance of a Metro public transit station are required to provide 0.8 spaces per bedroom, but this requirement is reduced by five percent in the following cases:
- The building is within one-quarter mile of four or more active bus routes
- The building has a walkability index score of 80 percent or above (buildings with a score of 90 to 100 are eligible for a 10 percent reduction in parking requirements)
- Twenty percent or more of the units in the building are studio apartments
Outside of Metro-accessible areas, multifamily buildings must provide one parking space per bedroom. However, reductions are possible in cases where the building is near a bus rapid transit stop or four or more active bus routes, in an area with a high walkability index score, or has a large proportion of studio apartments. In calculating the number of spaces required for multifamily buildings, Alexandria allows any development to disregard additional bedrooms after the first two. Multifamily buildings that include affordable housing are also eligible for additional flexibility in parking requirements. Read more about Alexandria’s parking and loading regulations.
Buffalo, NY approved the Unified Development Ordinance in 2016, moving to a form-based code focused on contextual and sustainable development. The new code eliminated a burdensome obligation to provide unnecessary and expensive off-street parking for adaptive reuse and infill projects. Moving toward a market-based approach will better align housing development with actual parking needs and reduce the total cost of development.
Policy design and implementation
- Consumer Expenditure Survey tables – Tables compiled by the U.S. Department of Labor Bureau of Labor Statistics provide vehicle ownership data by household income level, housing tenure, location, age, and other factors.
- Parking Management: Comprehensive Implementation Guide, Victoria Transport Policy Institute (July 2017) – While not limited to residential parking requirements, this guide provides detailed information on policies and programs that can be used to improve the efficiency of existing parking management systems. The report includes a list of potential parking requirement adjustment factors and typical adjustments (Table 11).
Parking requirements and housing affordability
- The Trouble with Minimum Parking Requirements, The University of California Transportation Center (1999) – Describes cost impacts of minimum parking requirements and presents alternative solutions for regulating parking supply.
- Searching for the Right Spot: Minimum Parking Requirements and Housing Affordability in New York City, NYU Furman Center (2012) – Examines how parking regulations affect developers’ decisions about what to build, explores the effect that the parking requirements may have on housing affordability, and highlights some options for reform.
- Rethinking Residential Parking: Myths & Facts, Non-Profit Housing Association of Northern California – Debunks popular misconceptions about parking, such as “Affordable housing in particular needs more parking” and “People will own the same amount of cars regardless of transit services, neighborhood characteristics and amount of parking spaces.” Includes case studies from cities in California.
- The Metro Vancouver Apartment Parking Study, Metro Vancouver (September 2012) – This technical report examines local data, emerging trends, and lessons from other cities to present findings and recommendations for multifamily apartment parking requirements in Vancouver, BC that will likely be applicable in other communities.