ADA Curb Ramps 2

[Pinwards]

A common situation in site and roadway design for new construction is the standard 6" vertical curb with a 2% cross-sloped sidewalk above, and an ADA-compliant pedestrian ramp is needed to transition from street/gutter level up to the sidewalk. Per the ADA guidance, any total rise in a ramp over 6" requires handrails:

2010 ADA: 405.8 Handrails. Ramp runs with a rise greater than 6 inches (150mm) shall have handrails complying with 505.


However, with a 6" curb and ANY slope (greater than zero) to the sidewalk above, the ramp would by definition exceed the 6" rise limit. Often these are constructed at 6' length because they are quickly calc'd at 1:12 longitudinal slope just for the height of the curb, ignoring the additional rise to catch the surface above. E.g. typical 0.50' curb + 0.02*6'ramp = 0.62' > 0.50' max rise (and in truth violates the 1:12 max longitudinal slope, the ramp should be almost 8' to catch a 2% sidewalk at 1:12 max). So how do jurisdictions justify omitting the handrail in curb ramps?

#

 

[darthsoilsguy2]

i don't know if there is explicit language to cite. maybe there is or maybe it is so common to have handrailess curb ramps that nobody ever considered putting language in to allow it. There is relief from longitudinal slope requirements when you're tied to a road.

the example you put out there looks very similar to the example "Case Study—Parallel Curb Ramps and Road Grade" about half-way down the page at this link which the access board doesn't say anything about handrails. interestingly enough, suggests you can exceed the 1:12 ramp slope maxes if you can't get there in 15 ft because the road grade is so aggressive.

https://www.access-board.gov/guidel...ign-for-alterations/chapter-5—model-sidewalks

 

[bridgebuster]

In NY - and most likely in other states because this is ADA - a sidewalk ramp/wheelchair ramp is not considered a "ramp" subject to ADA. A ramp under ADA has a maximum slope of 5% and requires handrails. It is assumed for sidewalk ramps that someone with a disability can maneuver a 1:16 slope because of the short length, however, 1:12 is used as the standard not be exceeded. Something also to consider: A handrail in a sidewalk ramp is a safety hazard because it is a traffic obstruction. It would have to be 18" from the curb to meet AASHTO, in which case the handrail wouldn't serve any purpose.

Check your state DOT requirements. This is a link to NYSDOT standards for sidewalk ramps.

https://www.dot.ny.gov/main/busines...andard-sheets-us-repository/608-01_050116.pdf

 

[Spartan5]

There is a specific section on Curb Ramps (406) which states which portion of Ramps (405) apply. 405.8 does not apply to Curb Ramps:

https://www.access-board.gov/guidel...ds/chapter-4-accessible-routes#406 Curb Ramps

 

[darthsoilsguy2]

jeez... if it were a snake it would have bit us Spartan5.

 

[Pinwards]

Thanks Spartan5, that's exactly the kind of response I was looking for. I'm not sure how I overlooked that note.

#