Height and Clearances. Lavatories shall be mounted with the rim or counter surface no higher than 34 in (865 mm) above the finish floor. Provide a clearance of at least 29 in (735 mm) above the finish floor to the bottom of the apron. Knee and toe clearance shall comply.

Lavatory Clearances.
The minimum knee clearance must be free of equipment or obstructions for a minimum of 8 inches (205 mm) extending from the front edge of the lavatory back toward the wall. This knee clearance must be 29 inches (735 mm) high at the front of the lavatory and no less than 27 inches (685 mm) high at a point 8 inches (205 mm) back. In addition, a minimum 9 inches (230 mm) high toe clearance must be provided extending back toward the wall to a distance no more than 6 inches (150 mm) from the back wall. The toe clearance space must be free of equipment or obstructions.

The maximum height of the lavatory is 34 inches (865 mm). The bottom edge of a wall-mounted mirror must be mounted no more than 40 inches (1015 mm) above the floor.

Clear Floor Space. A clear floor space 30 in by 48 in (760 mm by 1220 mm) complying with 4.2.4 shall be provided in front of a lavatory to allow forward approach. Such clear floor space shall adjoin or overlap an accessible route and shall extend a maximum of 19 in (485 mm) underneath the lavatory.

Clear Floor Space at Lavatories

Clear Floor Space at Lavatories.
The minimum depth of the lavatory is 17 inches (430 mm). A clear floor space at least 30 inches (760 mm) wide and 48 inches (1220 mm) long is required for a forward approach in front of the accessible lavatory. The clear floor space shall extend up to 19 inches (485 mm) maximum into the kneespace below the lavatory.