Slope / Length / Rise Chart

Inches of Rise	1:12 Slope*	1:8 slope*	2:12 Slope*	3:12 Slope*
3" ramp rise	3' ramp required	2' ramp required	2' ramp required	1' ramp required
4" ramp rise	4' ramp required	3' ramp required	2' ramp required	1' ramp required
5" ramp rise	5' ramp required	3' ramp required	3' ramp required	2' ramp required
6" ramp rise	6' ramp required	4' ramp required	3' ramp required	2' ramp required
7" ramp rise	7' ramp required	5' ramp required	4' ramp required	2' ramp required
8" ramp rise	8' ramp required	5' ramp required	4' ramp required	3' ramp required
9" ramp rise	9' ramp required	6' ramp required	5' ramp required	3' ramp required
10" ramp rise	10' ramp required	7' ramp required	5' ramp required	3' ramp required
11" ramp rise	11' ramp required	7' ramp required	6' ramp required	4' ramp required
12" ramp rise	12' ramp required	8' ramp required	6' ramp required	4' ramp required
13" ramp rise	13' ramp required	9' ramp required	7' ramp required	4' ramp required
14" ramp rise	14' ramp required	9' ramp required	7' ramp required	5' ramp required
16" ramp rise	16' ramp required	11' ramp required	8' ramp required	5' ramp required
18" ramp rise	18' ramp required	12' ramp required	9' ramp required	6' ramp required
20" ramp rise	20' ramp required	13' ramp required	10' ramp required	7' ramp required
22" ramp rise	22' ramp required	15' ramp required	11' ramp required	7' ramp required
24" ramp rise	24' ramp required	16' ramp required	12' ramp required	8' ramp required
26" ramp rise	26' ramp required	17' ramp required	13' ramp required	9' ramp required
28" ramp rise	28' ramp required	19' ramp required	14' ramp required	9' ramp required
30" ramp rise	30' ramp required	20' ramp required	15' ramp required	10' ramp required

* see slope reference below:

 

• 1:12 Slope (Or 9.85%, 5 degree incline)

• The ADA recommended slope for commercial and public access ramps.
• Works for most manual chair users unassisted.

• 1:8 Slope (Or 12.5%, 7 degree incline)

• Most unassisted manual chair users can use on short ramps.

• 2:12 Slope (Or 16.7%, 9.5 degree incline)

• OK for most portable ramps.
• An able assistant required for those unable to power themselves.

OK for strong, unassisted manual chair users.

• 3:12 Slope (Or 25%, 14.5 degree incline)

• Stability a concern.
• Clearance under scooter at top of ramp needs to be considered.
• Works for lightweight chair/user with strong assistant.
• Works for loading unoccupied power chairs and scooters.
• Only the strongest unassisted manual chair users can use on short ramps.