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ADA Accessibility Quick-Reference

A visual guide to ADA accessibility requirements including ramp slopes, door clearances, turning radii, and restroom dimensions. Essential reference for ensuring your designs meet accessibility standards.

Key statistics

According to the U.S. Access Board, 61 million Americans (26% of adults) have a disability, and accessibility violations remain the most common ADA lawsuit trigger. The National Council on Disability reports that ADA-related construction litigation costs average $75,000-$150,000 per case, not including remediation costs. The most common violations are improper ramp slopes, insufficient door maneuvering clearances, and non-compliant restrooms.

Quick jump
Ramp RequirementsDoor ClearancesTurning & Maneuvering SpaceAccessible RoutesRestroom Clearances
The numbers you need to know
1:12
Max Ramp Slope
32"
Min Door Clear
60"
Turning Diameter
36"
Min Route Width

Ramp Requirements

Maximum Slope
1:12
For every 1 inch of rise, minimum 12 inches of run required
Cross Slope
1:48 max
Maximum cross slope perpendicular to direction of travel
Maximum Rise per Run
30 inches
Maximum vertical rise before a landing is required
Minimum Clear Width
36 inches
Clear width between handrails
Landing Length
60 inches min
Required at top, bottom, and direction changes
Landing Width
60 inches min
At least as wide as the widest ramp run
Handrail Trigger
6" rise or 72" run
Handrails required on both sides when exceeded

Door Clearances

Minimum Clear Opening
32 inches
Measured between face of door and stop when open 90 degrees
Ideal Clear Opening
36 inches
Recommended for easier wheelchair passage
Maximum Threshold Height
1/2 inch
Thresholds must be beveled if over 1/4 inch
Maneuvering Clearance (Pull Side)
60" x 18"
Clear floor space on pull side of door
Maneuvering Clearance (Push Side)
48" x 0"
Clear floor space on push side (latch approach)
Door Opening Force
5 lbs max
Maximum force to open interior doors (fire doors exempt)

Turning & Maneuvering Space

Circular Turning Space
60" diameter
For 360-degree wheelchair turns
T-Shaped Turning Space
60" x 60"
Alternative to circular, with 36" arms
180° Turn at Obstruction
42" + 48" + 42"
Width approaching, at turn, and leaving
Minimum Passage Width
36 inches
Can reduce to 32" for max 24" length
Two Wheelchair Passing
60 inches
Minimum width for two wheelchairs to pass

Accessible Routes

Running Slope
1:20 max
Maximum slope before considered a ramp
Clear Width
36 inches min
Continuous clear width of accessible routes
Headroom
80 inches min
Minimum vertical clearance along route
Changes in Level (Vertical)
1/4" max
Without edge treatment
Changes in Level (Beveled)
1/2" max
With 1:2 beveled edge
Protruding Objects
4" max
Maximum protrusion into circulation path (27"-80" height)

Restroom Clearances

Accessible Stall Width
60 inches min
Clear width for wheelchair accessible stall
Accessible Stall Depth
56-59 inches
Wall-mounted (56") vs floor-mounted (59") toilet
Toilet Centerline
16-18 inches
Distance from side wall to toilet centerline
Grab Bar (Side)
42 inches
Minimum length of side grab bar
Grab Bar (Rear)
36 inches
Minimum length of rear grab bar
Lavatory Knee Clearance
27" high x 30" wide x 11" deep
Minimum knee and toe clearance under lavatory

Frequently Asked Questions

What is the maximum ramp slope allowed by ADA?

The maximum ramp slope is 1:12 (8.33% or 4.8°), meaning for every 1 inch of vertical rise, you need at least 12 inches of horizontal run. For example, a 30-inch rise requires a minimum 30-foot ramp length. Ramps with slopes steeper than 1:20 but no steeper than 1:12 require handrails on both sides.

What is the minimum clear door width for ADA compliance?

The minimum clear opening width is 32 inches, measured between the face of the door and the stop when the door is open 90 degrees. A standard 36-inch door typically provides 34-35 inches of clear width when accounting for hardware. For easier wheelchair passage, 36 inches clear is recommended.

What is the ADA turning radius requirement?

ADA requires a 60-inch diameter circular space or a 60-inch x 60-inch T-shaped space for wheelchair turning. The T-shape must have arms at least 36 inches wide. This space must be provided at key locations including within accessible restroom stalls, at the end of dead-end corridors, and at building entrances.

Sources & References

  • 2010 ADA Standards for Accessible Design, U.S. Department of Justice
  • ICC/ANSI A117.1-2017: Accessible and Usable Buildings and Facilities
  • U.S. Access Board: ADA Accessibility Guidelines (ADAAG)
  • Fair Housing Act Design Manual, U.S. Department of Housing and Urban Development
  • CDC Disability and Health Data System (2023): Disability Prevalence Statistics
  • National Council on Disability: ADA Compliance Cost Analysis (2022)

Requirements based on ADA Standards for Accessible Design. For official guidelines, visit the U.S. Access Board. Always verify requirements with your local Authority Having Jurisdiction (AHJ).

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Automate your ADA compliance checks

Tired of manually checking door clearances, ramp slopes, and turning radii on every drawing? Helonic's AI can scan your PDFs and flag potential ADA violations with exact locations in seconds. Catch accessibility issues before they become expensive field corrections.