Calculations apply not only to walkers, manual wheelchairs, power wheelchairs and scooters, but also to individuals that may have impaired walking due to injury, amputation, surgery, or balance issues.
The ADA 4.8° rule:
1 inch rise per 12 inch ramp length = 4.8°
Public and commercial properties we recommend you stick with the ADA requirements of 4.8° and the longer ramp lengths.
The incline chart below will help calculate the length of ramp needed for most situations and settings. Keep in mind, the ADA standard ratio (for commercial & public properties) is 1:12 slope which means for every 1" of vertical rise you are required to have at least one foot of ramp (4.8° incline). And this is for loading unoccupied wheelchairs/scooters.
The 14.5° rule:
However, for home use, this is not always achievable or practical. Try the 14.5° rule, 3:12 ratio. You can calculate this by dividing the rise in inches by 3 (24 inch rise requires an 8 foot ramp).
9.6° for power wheelchairs & scooters:
Always consult your equipment's owner guide to see what degree of incline is recommended. A typical power wheelchair recommended incline capability is about 9.6° with the patient in the chair or scooter and about 14.5° unloaded. Pushing a manual wheelchair can be difficult or easy depending on: ramp length + patient weight.
Ramp Length Calculator Back To AnyCalculator.com