The shortest distance between two points is not always a straight line. If you use a wheelchair, the shortest distance between an accessible parking space and the entrance to your favorite retail store is often detoured across a curb ramp. Wheelchair users rely on accessible curb ramps to overcome changes in elevation that separate parking lots from accessible spaces like shopping centers. Whenever an accessible route crosses a curb, an accessible curb ramp is required. While curb ramps can be helpful for those pushing shopping carts or baby strollers, they are absolutely crucial for wheelchair users. There are a few important things to keep in mind when providing accessible curb ramps. Below are some key design requirements to think about in curb ramp design.
- Similar to general accessible routes, curb ramps should be at least 36 inches wide. However, wider curb ramps are recommended since traffic will use them in both directions. Traffic can also be heavy on curb ramps since they are used by everyone.
- Slopes of curb ramps should not exceed those requirements found in standard ramp design. This means curb ramps should not have running slopes that exceed 1:12 or 8.33 percent.
- Also like ramps, curb ramps should have level landings at both the top and the bottom. While a standard ramp requires a 60 inch deep landing, curb ramps only require a 36 inch deep landing. The width of the landing should be at least as wide as the curb ramp.
- Flairs, though not required, cannot be steeper than 1:10 or 10 percent. Flairs can be especially helpful if clearances at the top of the curb ramp are tight. Flairs allow a user to enter or exit the curb ramp at angles.
- Ensure transitions from the curb ramp to other surfaces are free of level changes. Often curb ramps are located at drive aisles where a curb meets a sidewalk. Pay special attention to the transition from one material to the next, for example the asphalt drive aisle and the concrete curb ramp. While ¼ inch vertical or ½ inch 1:2 bevel is allowed, flush transitions are recommended and best.
- Lastly, curb ramps must be connected to accessible routes. Ensure accessible route at both the top and the bottom of curb ramps are not obstructed by other objects. Wider curb ramps sometime receive bollards to prohibit automobiles from entering. If bollards are provided, do not let them obstruct the curb ramp or the accessible routes.
Details for curb ramp design can be found in both the 2010 Standards for Accessible Design (section 406) and in the 2003 edition of ICC/ANSI A117.1 (section 406). Keep in mind that all curb ramps must comply with these requirements. In exiting building, ensure that curb ramps associated with accessible routes are in fact accessible. All other curb ramps should be removed to avoid confusion or made to comply.