Learn the correct measurements of a properly constructed wheelchair ramp:
- Maximum slope for hand-propelled wheelchair ramps should be 1" of rise to every 12" of length (4.8 degree angle; 8.3% grade).
- Maximum slope for power chairs should be 1.5" rise to 12" length (7.1 degree angle; 12.5% grade).
- Minimum width should be 36" (inside rails) - (48" is ideal).
- The "deck" or surface of the ramp should be set down between a side-rail assembly such that there is about a 2" curb or lip along the edges of the ramp surface. Decking could consist of 1" X 6" pressure treated pine, (or 3/4" pressure treated plywood applied to a frame).
- If possible, the end of the deck (where it meets the lower ground surface) should be beveled to provide a smooth transition from the ramp to level ground. Alternatively, a sheet of 10 Ga. steel at least 10" long and sized to fit the width of the ramp could be used to span the space between the deck surface and the walk or driveway surface at the end of the ramp. This piece should overlap the ramp deck by 2" and be fastened securely with 4 large countersunk flat-head wood screws.
- A level platform of at least 5' X 5' should be at the top of ramp to allow for wheelchair maneuvering. If the entranceway opens outward, there should be 1' of surface area extending from the side of the door opening to allow motion to the side without backing the chair during door opening. This landing should not be considered part of the overall "run"/length of the ramp. Any turning point along the ramp needs a level landing. If the turn is a right angle (90 degrees), the landing should be a minimum of 5' by 4'. If a "switchback" of 180 degrees is constructed, the level landing should measure at least 5' X 8'. Ramps longer than 30' should provide a platform every 30' for purposes of safety and to create opportunity for rest.
- Hand rails should be provided for any ramp having a slope of more than 5% (i.e.- greater than 1:12). These should extend an inch beyond the top and bottom of the ramp and should be located 32" from the ramp surface.
- Buildings modified for accessibility should provide at least 2 remotely located accessible entrances for exit in case of emergency.
- There should be no step or bump exceeding one-half inch at doors or thresholds and there should be a level area 5' by 5' at doors. 1' to 1'6" space to the side of door on the pull side must be clear.
- Slip resistant surfaces - carborundum grit, strips, rubber, sand sprinkled on wet paint, or rough ("broom finish") concrete are acceptable surfaces.
- Ramps should have a 5' straight and level surface at the bottom to allow adequate stopping distance.
Use the calculator below by selecting the type of ramp and entering any variable to determine the length or height of your ramp.