All You Need to Know About ADA Curb Ramp Requirements

The Americans with Disabilities Act (ADA) includes requirements to make public areas accessible to wheelchairs, walkers, and motorized scooters through the use of ramps.1 These requirements are based on specific guidelines, depending on the type of ramp in use, its location, and other such factors.

Without curb ramps, curb edges and accessibility would create hazards for those people with disabilities. There are increased risks of falling out of a wheelchair or scooter or tripping while using a walker when going over an elevated curb. In addition, restricting access in public areas under current federal laws could be construed a form of discrimination against such individuals.2

ADA Wheelchair ramp sign


To help you have a better understanding of the ADA ramp specifications and requirements, we will look at some of the more commonly asked questions by business owners, building managers, and construction companies.

Where are curb ramps and ramps required by the ADA?

A facility must install curb ramps or ramps in public areas along accessible routes where there is a change in levels greater than one-half inch. However, in lieu of installing curb ramps and ramps, a facility may provide accessibility using elevators or platform/chair lifts.1 Furthermore, any accessibility routes which have a slope steeper than five percent have to be treated under the ADA ramp guidelines.

What is the minimum width requirement of curb ramps and ramps?

According to the ADA requirements, curb ramps and ramps must have a minimum width of at least thirty-six inches.1 If handrails, indentations, or other features are incorporated into the ramp’s design, they must not reduce the width below the thirty-six-inch requirement.

What is the maximum allowed rise for curb ramps and ramps?

The maximum allowed rise—the overall height of the ramp at its highest point—cannot exceed thirty inches. For heights that will exceed thirty inches, it is perfectly acceptable to install several smaller ramps with landing places in between each one.

handicapped curb ramp

Is there a maximum length curb ramps and ramps can be?

The ADA requirements do not have any restrictions on the length of curb ramps and ramps unless they exceed thirty inches in height. Then one must break up the ramp through the use of landings. However, excessively long ramps can be tiresome for those in wheelchairs or using walkers. In these cases, a chair/platform lift might be a much more appropriate solution.

What are the slope requirements for curb ramps and ramps?

The slope is directly related to the rise (height) and length of the ramp. The ADA curb ramp slope standards require the slope to be no more than a maximum of a 1:12 ratio or 8.33%. The slope must be uniform from one end of the ramp to the other, with a few exceptions for slight variations in the materials used to create the ramp. The only other exception is in regards to cross-sloped ramps, where the cross slope maximum is a ratio of 1:48. Furthermore, side flares used with certain curb ramp designs can only have a maximum of a 1:10 ratio.1

Are landings required as part of the curb ramp or ramp design?

Landings are required at the top and bottom of ramps, while curb ramps only require landings at the top. Landings should provide a minimum of sixty inches long and at least thirty-six inches wide for single ramps.1 Ramp landings may overlap door opening clearances so long as the door does not open into the landing area. It is highly recommended, when overlaps occur, for the door to swing open in the direction opposite the landing.

In ramp configurations that have multiple landings, each landing section has to be sixty inches long and sixty inches wide to allow for easier maneuverability. Curb ramps and ramps must also be designed to prevent the accumulation of water on the ramp itself, on landings, and at the bottom of the curb transition to the lower surface.

Benefits of Handicap Ramps

Where can built-up curb ramps be used?

Built-up curb ramps are ramps that are added off of a curb to allow for access. These are perfectly acceptable alternatives to use in certain locations, such as parking lots. However, they cannot project into vehicle traffic lanes, bus lanes, or bike paths. Nor can they project into parking spaces or restrict access to aisles.

Another alternative when a built-up curb ramp is not feasible and there is limited space is to install parallel curb ramps. This design is where there are ramps which run parallel to the sidewalk and that have landings which are a minimum of forty-eight inches wide at the base of each ramp.3

Can raised crossings be used instead of curb ramps?

Raised crossings are allowed under the ADA guidelines in locations where the entire crossing is raised to the elevation of the curb. For specific requirements, you need to review your local requirements in regards to the width, height, appropriate markings, and so on.

intersection curb ramp

What are the requirements for curb ramps used at intersections?

The ramp section, excluding flared sides, must be within the allowed space for the crosswalk, regardless of the markings used in the intersection. Curved curbs should have ramps placed so they are perpendicular around corners while still within the crosswalk space.1

Diagonal curb ramps are allowed to be used in place of two separate ramps for each crosswalk. However, the ramp must still transition at the bottom into the street inside the marked crossings for both crosswalks.

Please keep in mind, it is your responsibility to fully review the latest requirements, as there are regular updates made to the ADA. The most recent ones were made in 2016.

Detectable Warning Systems and Ramps and Curb Ramps

Aside from specific requirements for ramps and curb ramps, the ADA also includes a section regarding the use of detectable warning systems. The use of tactile raised domes at the top and bottom of ramps is not always required, except when used in public transportation areas, such as subways, train stations, and bus stations.

It is worth noting, both the Department of Justice (DOJ) and Department of Transportation (DOT) have their own requirements in regards to the use of detectable tactile warning systems. These requirements can be in addition to those contained within the ADA.

detectable tactile warming systems

For curb ramps, the DOJ and DOT require that raised domes are used in areas that receive funding from the Federal Highway Administration, as well as in federal, state, and local government facilities.

However, since visually impaired individuals tend to use ramps and curb ramps for access, it is highly recommended that, even when there is no federal, state, or local requirement, facilities should still install truncated dome panels at the top and bottom of ramps to indicate a change in surface.

When the use of tactile warning curb ramps is required by federal, state, or local laws, they must comply with specific guidelines in regards to spacing, size, and contrast with the regular pavement surface. For instance, California laws have adopted the use of yellow as the only allowed color, with a few exceptions.

Furthermore, the placement of the warning surfaces can and does vary based on the location where it installed. For instance, in subway and rail stations with elevated platforms, the truncated domes must run the entire length of the platform.

ada compliant painted sidewalk

For more information about ADA sidewalk requirements and assistance in selecting the appropriate tactile warning systems, please feel free to contact ADA Solutions today at (800) 372-0519! We offer a variety of solutions, from cast-in-place replaceable to radius systems in a variety of colors and cast iron, as well as photoluminescent systems.