About the Calculator

What does it do?

The Park Right DC calculator helps community members, developers, zoning bodies, planners, and other stakeholders better understand parking utilization in multi-family residential buildings in the District of Columbia. By weighing factors that affect parking use at multi-family housing sites, the calculator helps users consider how much parking is “just enough” when making regulatory and community decisions about development.

The calculator produces parking use estimates in the context of a specific site, based on a model using current local data of actual parking use correlated with factors related to the building and its surroundings.

The calculator’s estimates are based on a model developed from extensive field work on data collected mostly in the fall of 2014 and spring of 2015 on over more than 90 multi-family buildings across the District.

Why parking matters

The supply and use of parking are influenced by—and have influences on—development practices, local policies, economic impacts on builders and households, urban design, and community goals. The supply and price of parking also have direct relationships with travel behavior. Too much parking at residential properties correlates with more automobile ownership, more vehicle miles traveled, more congestion, and higher housing costs. In addition, excess parking presents barriers to smart growth and efficient transit service. Conversely, too little parking can have adverse impacts on curbside parking utilization.

Parking supply and pricing often have a direct impact on the ability to create compact, healthy communities. Sustainable DC and moveDC set aggressive targets for population and job growth and non-auto travel. To help meet these goals, the District has an interest in encouraging land uses, policies, and development that lead to communities that can be served efficiently and effectively by transit, walking, and biking. To that end, a better understanding of parking utilization in multi-family residential buildings is an important starting point for discussions about accommodating anticipated growth while maintaining a high quality of life in the District.

Who’s Involved?

This calculator was developed jointly by the District Department of Transportation (DDOT) and the District of Columbia Office of Planning (OP) with consultant support from local and national leaders in parking and transportation planning.

The Park Right DC Calculator builds on past efforts such as King County’s (Washington) Right Size Parking Calculator developed as part of King County Metro Transit’s Right Size Parking Project. For more information on King County’s work, see the King County Right Size Parking Calculator website.