Summary

With more multi-family housing projects on the drawing board to accommodate King County’s growing population, how will developers know how much parking should be added to meet the future needs of their tenants?

Story

Online calculator developed by King County Metro Transit helps strike a balance between parking supply and demand

With more multi-family housing projects on the drawing board to accommodate King County’s growing population, how will developers know how much parking should be added to meet the future needs of their tenants?

That’s a tough call for many in the industry – and one that will become even tougher as cities become more urbanized and people have increased options for getting around.

And it’s why King County Metro Transit is betting on a new calculator that will go a long way toward demystifying parking supply and demand in multi-family developments.

Metro has just completed the first phase of a grant-funded research project that looked at some hard numbers: How many existing parking spaces in housing developments all across the county are actually being used?

The findings may come as a surprise. Despite the long-held belief that almost every household owns at least one vehicle, the research points to a formula that is more complex. A combination of factors, such as location, price of parking, the proximity of housing to jobs and access to good bus service are the true drivers of parking demand. While one household may need two cars, a growing number of households living in denser urban areas are choosing to go carless.

Developers looking to minimize parking costs first consider the importance of site characteristics and location for their projects. In addition to these location characteristics, developers can control a range of factors, most importantly the price of parking.

The findings of the study show that on average, multi-family residential developments offer 1.4 parking spaces per unit - yet only one space is actually being used. The oversupply adds to higher housing costs and may not be the best use of available land.

The research also concluded that the right number of spaces per unit varies among locations, which suggests parking requirements that work in Seattle are different than those in Bellevue or Kirkland, or other cities.

More than 200 housing complexes were surveyed for the study and 100 factors analyzed to determine the relationship between parking supply and demand. The results have now been incorporated into an online map-based rightsizeparking.org calculator that will serve as a tool to help guide future residential parking requirements.

“This research shows that through better parking management we have a win-win opportunity to provide more affordable housing and at the same time create more sustainable transit and pedestrian-friendly communities,” Metro General Manager Kevin Desmond said.

The research project was funded by a Federal Highway Administration Value Pricing Pilot Program grant and was carried out in partnership with the Center for Neighborhood Technology, Urban Land Institute and Washington State Department of Transportation.

For more information about the “right-size” parking project, visit www.kingcounty.gov/RightSizeParking