Illustrated Rules of Good Bathroom Design

Guideline 5: Single Lavatory Placement


Recommendation: The distance from the centerline of the lavatory to the sidewall/tall obstacle should be at least 20”.


Building Code Requirement:

  • The minimum distance from the centerline of the lavatory to a wall is 15″. (IPC 405.3.1)
  • The minimum distance between a wall and the edge of a free standing or wall-hung lavatory is 4″. (IRC R 307.2)


  1. A pedestal or wall mounted lavatory must meet both of the Building Code Requirements. The center of the lavatory must be at least 15″ away from any side wall or tall obstacle, such as a tall cabinet, and the edge of the lavatory must be 4″ from the wall or tall obstacle. There are practical reasons for the 4″ requirement. Any closer and it would be very difficult to clean the lavatory.
  2. In a small bath remodel, careful attention needs to be paid to the size of lavatory sinks to ensure that minimum offset distances are met. When in doubt, go smaller. Almost all fixture manufactuters make lavatory sinks designed to fit very small spaces.