Vehicle Access Easement Standards

SDCI receives many multifamily and commercial short plat and lot boundary adjustment applications proposing ten-foot-wide vehicle access easements for lots with no street frontage.  These proposals base the width of the vehicle access on the number of parking spaces. However, Seattle’s Code (SMC 23.53.025) requires vehicle access widths to be based on the number of dwelling units being served, not the number of parking spaces being provided. (Under the code, the access requirements are distinct from driveway standards, which are based in part on the number of parking spaces served.)

Seattle’s code requires:

  • Vehicle Access Easements serving one or two single-family dwelling units or one multifamily residential building with up to two units should be at least 10 feet wide, or 12 feet wide if required by the Fire Code.
  • Vehicle Access Easements serving at least three but fewer than ten single-family units, or multifamily dwelling units should be at least 20 feet wide.
  • Driveways serving ten or more residential units must at least 32 feet wide.


We require projects to meet these standards even for if the developments do not require or provide parking. Even if the development does not have parking, projects need to provide adequate access for emergency vehicles.

Please keep in mind that when an easement serves fewer than 10 residential units and crosses a residentially zoned lot, portions of structures may be above the easement. Those portions of the structure must have a minimum vertical clearance of 16 ½ feet above the surface of the easement roadway.

Our customers have expressed confusion over how the easement standards apply to projects with little or no parking. SDCI will continue to process applications that we have already accepted. However, beginning November 1, 2017, all proposed development must be designed to meet the easement widths as indicated above.