ADA sidewalk requirements: width, slope, passing spaces and surface

Which rules apply to a sidewalk: PROWAG and the 2010 Standards

PROWAG, the Public Right-of-Way Accessibility Guidelines, covers newly built pedestrian facilities and the altered parts of existing ones in the public right-of-way (PROWAG, R201.1), temporary facilities included (PROWAG, R201.2). The public right-of-way is public land acquired for or dedicated to transportation, or land where the public has a legally established right to use it for transportation (PROWAG, R104.3). A sidewalk, in its words, is the paved or improved part of a highway between the curb line and the adjacent property line, intended for pedestrians (PROWAG, R104.3).

The Access Board published PROWAG as a final rule on August 8, 2023 (PROWAG). Guidelines are not binding on their own: they become enforceable once they are adopted as standards under the ADA by the Department of Justice and the Department of Transportation, or under the Architectural Barriers Act by the four agencies that set standards for federal facilities, the Postal Service, the General Services Administration, the Department of Defense and the Department of Housing and Urban Development (PROWAG, preamble). The Access Board’s PROWAG page lists two adoptions: the General Services Administration on July 3, 2024, and the Department of Transportation on December 18, 2024, as part of its ADA standards for new construction and alterations of transit stops in the public right-of-way (PROWAG).

PROWAG does not address existing sidewalks unless they are altered. The existing facilities of state and local governments fall under the Department of Justice’s program access rules, and whether PROWAG applies to them is for the Department of Justice to decide (PROWAG, R101.4). The preamble notes that, without final standards for streets, courts have in some cases applied the requirements for buildings and sites to public rights-of-way (PROWAG, preamble).

The 2010 ADA Standards define a site as a parcel of land bounded by a property line or a designated portion of a public right-of-way (2010 ADA Standards, definition of “site”). On a site, at least one accessible route runs from public streets and sidewalks, accessible parking, passenger loading zones and public transportation stops to the accessible entrance they serve (2010 ADA Standards, 206.2.1). The walks along that route are walking surfaces, and walking surfaces that are part of an accessible route follow section 403 (2010 ADA Standards, 403.1), compared with PROWAG further down this page.

Passing spaces: 60 by 60 inches, every 200 feet

Where the pedestrian access route is narrower than 60 inches (1525 mm), it needs passing spaces at intervals of 200 feet (61 m) at most. Each one is at least 60 by 60 inches (1525 × 1525 mm), and it may overlap the route itself (PROWAG, R302.3). On a 48-inch sidewalk, that means a 60-inch square of clear pavement at least every 200 feet.

The preamble gives the reason: 60 by 60 inches is enough room for two people in wheelchairs to pass each other. Two hundred feet is a maximum, so a city can place passing spaces closer together, for example to keep them away from a rail crossing where pedestrians are channeled (PROWAG, preamble).

The 2010 Standards use the same rule on a site, with a second option: an accessible route narrower than 60 inches has a passing space at least every 200 feet, either a 60-inch square or an intersection of two walking surfaces that forms a T-shaped space whose base and arms extend at least 48 inches (1220 mm) beyond the intersection (2010 ADA Standards, 403.5.3 and 304.3.2). The T-shape is drawn in ADA turning space.

Cross slope: 1:48, and what changes at crosswalks

Cross slope is the slope across the direction of travel (PROWAG, R104.3). Outside a crosswalk, the pedestrian access route has a cross slope of 1:48 (2.1 %) at most (PROWAG, R302.5.1). The one exception is the stretch of street that connects an accessible parallel on-street parking space to the nearest crosswalk at the end of the block or to the nearest midblock crosswalk (PROWAG, R302.5.1, exception). On a site, walking surfaces have the same 1:48 limit (2010 ADA Standards, 403.3).

The figure is not new. The preamble calls 1:48 well established in accessibility guidelines as the cross slope most people in manual wheelchairs and people with balance impairments can manage, and traces it back to the federal accessibility standards of 1984. It also explains that 1:48 is 2.08 %, written as 2.1 % because the digital levels used in sidewalk construction round to one decimal (PROWAG, preamble). A requirement stated as a maximum is a range from zero up to it, so industry tolerances are not added on top (PROWAG, R103.1); the preamble suggests designing below the maximum to absorb construction inaccuracies (PROWAG, preamble).

Inside a crosswalk, the cross slope of the walking route is the grade of the road it crosses. Where cars stop or yield, the road can be flatter at the crossing; where they drive through without slowing, the preamble explains, abrupt changes in the road’s grade are kept to a minimum so vehicles do not jolt, which is why those crossings allow 1:20 (PROWAG, preamble). In alterations, where existing physical constraints make full compliance technically infeasible, a requirement applies to the maximum extent feasible (PROWAG, R202.3).

Protruding objects and headroom

Clear width keeps the ground free; the protruding object rules deal with what hangs over the path. They apply to the whole pedestrian circulation path, not only to the 48-inch route (PROWAG, R207.1), and the preamble explains why: a wheelchair user can see which part of a sidewalk is flatter, but a blind pedestrian cannot know which strip has been designated as the route, so an object a cane cannot detect is a hazard anywhere on the sidewalk (PROWAG, preamble).

The 27-inch line is about the cane. The advisory note in the 2010 Standards puts it this way: an element in the range a cane can detect gives its user time to find it before the body touches it. The same note says awnings and their supports may not reduce the required headroom, and an open casement window may not stick out more than 4 inches above 27 inches (2010 ADA Standards, advisory 307.2).

On a site, the 2010 Standards use the same 4-inch projection, the same 27- and 80-inch heights and the same rule for signs between posts, with one difference: an object on a post may overhang the path by 12 inches (305 mm), where PROWAG allows 4 inches (2010 ADA Standards, 307.2 to 307.4). On a site, too, protruding objects may not reduce the clear width of the accessible route (2010 ADA Standards, 307.5).

When a sidewalk is closed for work

When a sidewalk is closed for construction, maintenance or a similar reason, an alternate pedestrian access route is provided, and it follows R303 and the protruding object rules of R402 (PROWAG, R201.2 and R204.1). Where site conditions or existing physical constraints make a detour technically infeasible, another way of providing access for pedestrians with disabilities is allowed (PROWAG, R204.1, exception).

• Width: 48 inches (1220 mm) at least, not counting the curb; where the detour uses an existing sidewalk, no narrower than the path that was closed (PROWAG, R303.4).
• Surface: the surface rules of the permanent route, or at least as accessible as the closed path (PROWAG, R303.3).
• Signs: placed ahead of the decision points, together with audible signs triggered by proximity or another non-visual way of giving the same information (PROWAG, R303.2).
• Edging: where barricades or other channelizing devices mark the detour, a continuous detectable edging runs along it, with its top at least 32 inches (815 mm) above the walking surface and its bottom no more than 2 inches (51 mm) above it; gaps are allowed where pedestrians or vehicles turn or cross (PROWAG, R303.6).
• Curbs and signals: where the detour crosses a curb, it has a curb ramp or blended transition, and where temporary pedestrian signals serve its crosswalks, they have push buttons or passive detection (PROWAG, R303.5 and R303.7).

Where the sidewalk meets the street

At corners and crossings, the sidewalk reaches the street through a curb ramp or a blended transition, placed under R203.6 and built under R304, with slopes and landings of their own (PROWAG, R203.6 and R304.1); they are explained in ADA curb ramp requirements. Curb ramps and blended transitions at crosswalks carry detectable warning surfaces (PROWAG, R205.2), and so do sidewalks at driveways controlled by stop or yield signs or by traffic signals (PROWAG, R205.7). The dome surface is described in truncated domes and tactile paving, and crossing signals that can be heard and felt in accessible pedestrian signals.

Checking the sidewalks around a place in Braillito Maps

The measurements above answer a practical question: can you get from the bus stop or the parking lot to the door? Braillito Maps is a community map of accessible places. In the Search tab you pick your city and filter by what you need, and you see the results as a list or on the map. Each place answers ten questions: step-free entrance or ramp, wide doorway, accessible restroom, accessible parking, tactile paving, braille signage, braille menu, audible signals, guide dogs welcome and a quiet environment. Each answer is yes, no or no data, and the score is the number of yes answers out of ten.

The sidewalk is not a question of its own, because the map describes places, not streets. It shows up in the answers around it. Step-free entrance or ramp tells you whether the last stretch to the door has steps. Accessible parking matters because on a site an accessible route has to lead from accessible parking spaces to the entrance they serve (2010 ADA Standards, 206.2.1). Tactile paving and audible signals tell a cane user what to expect on the way in. For the sidewalk itself, the six checks above take a couple of minutes on the spot.

When you add a place, mark only what you saw and leave the rest without data. If the entrance has a ramp but the sidewalk in front of it is blocked by a pole or tilts steeply toward the street, that is worth knowing before you mark the ramp, so the next person does not make the trip for nothing. Meet Braillito Maps.

More accessibility guides

• ADA curb ramps: curb ramp slope, counter slope, width, flared sides, the top landing, diagonal ramps, islands and detectable warnings.
• ADA ramp slope: the 1:12 rule, width, landings, handrails and edge protection.
• Truncated domes and tactile paving: what the bumps on curb ramps and platform edges mean, and their sizes in the US and the UK.
• Accessible pedestrian signals: how the push button, the locator tone, the walk tick and the vibrating arrow tell blind pedestrians when to cross.
• ADA turning space: the 60-inch turning circle, the T-shaped turn, the 30 by 48 inch clear floor space and where the ADA asks for each.
• The white cane: what it tells the person using it and the people around them, and White Cane Safety Day.
• ADA compliance: a checklist for small businesses, with the 2010 Standards section behind each item.
• ADA hallway width: clear width of hallways and corridors, the 32-inch exception, width at turns, passing spaces, floor and slope, and objects that stick out from the walls.
• ADA paratransit: who qualifies, the 3/4 mile service area, fares up to twice the bus fare, next-day booking, companions and how to apply.
• All accessibility guides