Definitions

• The ADA requires that all newly constructed or renovated buildings allow for easier access to people with disabilities by providing for at least one disability access route to and from the entrance of the building to any parking space or public transportation facility. Any part of these routes that exceeds a grade of 1:20 is considered a ramp under the ADA, and must provide for any requirements made for such ramps.
  
  

Grade

• Slope ratios are as the relationship between vertical height, or rise, to horizontal length, or run. For example, a slope of 1:20 means there is 1 foot of rise for every 20 feet of length. Lower ratios such as 1:5, for example, means the slopes are steeper than higher ratios such as 1:30. While any slope greater than 1:20 must be considered a ramp, no ramp can have a cross slope grade of greater than 1:50. In general, ramps can be no steeper than 1:12. Further, the maximum rise allowed for any ramp is 30 inches in any section. If the rise is greater, a level landing area must be used to break the ramp into sections.
  
  

Dimensions

• All ramps generally must be at least 36 inches wide,or provide at least 36 inches of open space between walls and handrails or other obstructions. Any landings used must be at least as wide as the ramp itself and must be at least 60 inches long.
  
  

Hand Rails

• Any ramp with a run longer than 72 inches or a rise higher than 6 inches must have a handrail on both sides. These rails must be able to withstand at least 1112 newtons of downward force and be between 1.25 and 1.5 inches in diameter.
  
  

Curbs

• Whenever an accessible route encounters a curb, the ramps that allow access from street level to sidewalk level must comply with slope and size requirements of ramps. However, curb ramps must have flared sides where they transition between ramps, gutters, or streets, and must be designated with alternating dark on light markings to allow for easier detection.