Measure Parking: Accessible Stalls and Access Aisles Using Centerline of Paint: A Complete Guide

Measure Accessible Parking Stalls and Aisles

Understanding how to properly measure accessible parking stalls and access aisles is crucial for ADA compliance. The 2010 ADA Standards provide specific guidance on measurement methods, with particular attention to how paint lines are used in these calculations.

Standard Measurement Method: Centerline Rule

The primary method for measuring accessible parking spaces and access aisles is from the centerline of paint markings. This applies to both the parking space width and the access aisle width when adjacent spaces or aisles exist on both sides.

For standard accessible parking spaces:

• Car parking spaces shall be 96 inches wide minimum

• Van parking spaces shall be 132 inches wide minimum (or 96 inches with a 96-inch access aisle)

• Access aisles serving car and van parking spaces shall be 60 inches wide minimum

The measurement process involves locating the center point of each boundary line and measuring from centerline to centerline. This method ensures consistency and accuracy across different line widths and painting applications.

Exception for End Spaces and Curb-Adjacent Areas

When there is no adjacent parking space or access aisle next to a space (such as when next to a curb, building wall, or at the end of a row), measurements are permitted to include the full width of the line defining the parking space or access aisle.

This exception recognizes practical situations where:

• A parking space is located at the end of a parking row

• A space is positioned adjacent to a curb

• An access aisle borders a sidewalk or building

• There is no adjacent parking space or aisle on one side

In these cases, the full width of the boundary line can be counted toward meeting the minimum width requirements, providing additional flexibility in design and measurement.

Practical Application Examples

Scenario 1: Standard Adjacent Spaces

When measuring two adjacent accessible parking spaces that share an access aisle, all measurements use the centerline method:

• Space 1: measured from centerline of left boundary to centerline of right boundary

• Access aisle: measured from centerline to centerline of its boundary lines

• Space 2: measured from centerline of left boundary to centerline of right boundary

Scenario 2: End Space Next to Curb

When an accessible parking space is positioned at the end of a row next to a curb:

• The side adjacent to other parking uses centerline measurement

• The side next to the curb can include the full width of the boundary line

• This allows the space to meet the 96-inch minimum width requirement more easily

Scenario 3: Access Aisle Adjacent to Sidewalk

When an access aisle borders a sidewalk or pedestrian area:

• The side adjacent to the parking space uses centerline measurement

• The side next to the sidewalk can include the full line width

• The aisle still must meet the 60-inch minimum width requirement

Compliance Citation Requirements

These measurement standards are established in the 2010 ADA Standards, Section 502.1, which states: "Where parking spaces are marked with lines, width measurements of parking spaces and access aisles shall be made from the centerline of the markings."

The exception is clearly defined in the same section: "Where parking spaces or access aisles are not adjacent to another parking space or access aisle, measurements shall be permitted to include the full width of the line defining the parking space or access aisle."

Understanding these measurement principles ensures that accessible parking facilities truly serve their intended purpose while maintaining compliance with accessibility regulations. Whether measuring spaces between other parking areas or adjacent to curbs and sidewalks, the centerline rule and its exceptions provide clear guidance for creating accessible parking that meets the needs of all users.

DISCLAIMER: The information provided in this post is for informational purposes only and does not constitute legal advice. Please consult a qualified attorney or consultant for advice tailored to your situation.