Ramps are necessary to connect different levels if elevators or lifts are not available. The American with Disabilities Act (ADA) standards for building a handicap ramp are minimum guidelines so people in a wheelchair can manage and safely use the ramp.
Slope and Rise
The maximum slope of a newly constructed ramp is 1:12 ratio. The maximum rise is thirty inches for any run length. These standards work for many yet, according to Handicap Ramp Design and Construction Guidelines, "the specifics of the disability and the means of movement" may affect the design. Examples include how the disabled individual sits in, or can maneuver, a wheelchair may require the landings to be wider or the slope to be less steep.
The minimum width for a ramp is thirty-six inches. This is the clear width between handrails, walls, or curbs.
There should be a landing area at the bottom and top of each run of a ramp. The width should be the same as the width of the ramp and the length of the landing should be a minimum of sixty inches. When the ramp has a change in direction, called a switchback ramp, the landing requirement is sixty inches by sixty inches.
A ramp that has a six inch or greater rise or a seventy-two inch or longer horizontal projection is required to have handrails on both side of the ramp. The inside rail on a switchback ramp needs to be continuous. The top of the handrail is thirty-four to thirty-eight inches above the ramp, space away from a wall surface is one and one-half inches, and the ends should be rounded or have a smooth return to a wall or floor.
If there is a drop-off for ramps and landing requirements include a minimum of a two inch curb or other way to prevent people from slipping off.
These ramps, landings, and approaches need to be built so that water and snow will not build up or accumulate on them.
Ramp surface cross slopes need to be less than a 1.50 ratio.