Handrail Extension?

[PBWolf]

Howdy all,

I have looked through the building codes and ADA, but couldn't really find where the requirements regarding "return" of the extension were defined. In all the diagrams, it shows a reverse "C", but the bottom portion of that "C" is not specified anywhere, which makes me question if it is actually required or not. Basically, I was wondering where (if at all) I could find those requirements, and if this hypothetical handrail/extension would meet current standards.

Thanks for your input as always.

 

[Yankee]

ICC/ANSI117.1-2003 Figure 505.10.3 Seems to explain your scenario and IMO yours does comply with that section.

 

[PBWolf]

Thanks Yankee. I really thought that it met those requirements, but like I said before, I just couldn't find anything defining the requirements of the bottom portion of the extension.

 

[Coug Dad]

The codes have change to require the bottom extension to be only one tread and not the old 12 inches plus one tread. IBC (2006) Section 1012.5.

 

[mark handler]

The EXISTING ADAAG requires the extention

The NEW ADAAG not yet adopted, does not require it

505.10.3 Bottom Extension at Stairs. At the bottom of a stair flight, handrails shall extend at the slope of the stair flight for a horizontal distance at least equal to one tread depth beyond the last riser nosing. Extension shall return to a wall, guard, or the landing surface, or shall be continuous to the handrail of an adjacent stair flight.

http://www.access-board.gov/ada-aba/final.cfm#routes

Some state like CA still require the extention

 

[PBWolf]

Mark, what height requirement would you be referring to?

 

[mark handler]

Top of gripping surfaces of handrails shall be 34 inches minimum and 38 inches max

If the handrail is set at the low number at the top, the break point will need to move at the bottom to maintain the minimums

 

[PBWolf]

Definitely. I currently have the handrail height set @ 36", so I think I am alright with those other clearances. Thanks for the heads up. Good eye :grin:

 

[Plans Approver]

117.1 shows the idealized vertical return by being perpendicular to the floor. However, your angled return is also subject to protruding object limitations in 117.1 - 307.2 and ADAAG 4.4.1. So the horizontal distance from the tip of the railing as it bends down to the where it meets the floor is 4" maximum.

edit: applies at top and bottom.

edit #2: 4" max at 27" above floor see figure 307.2 in 117.1 or 8a in ADAAG.

 

[FredK]

While I give you an "a" for effort I always wonder why someone wants to re-invent the wheel. Your drawing meets one section and fails another. The only thing missing is the 27 in above floor from 307.

307 Protruding Objects

307.1 General. Protruding objects shall comply with 307.

307.2 Protrusion Limits. Objects with leading edges more than 27 inches (685 mm) and not more than 80 inches (2030 mm) above the finish floor or ground shall protrude 4 inches (100 mm) maximum horizontally into the circulation path.

So go back to the regular drawing and save some grief and headaches.

 

[PBWolf]

In this case, I am "reinventing the wheel" because "the wheel" is ugly.

Thanks for the comments regarding the protruding objects, I have since revised my drawings to reflect that.

 

[Examiner]

If you want the angle then the outer most point of the top handrail cannot be more than the distance of a protruding object from the point the rail is attached to the grade. Cane detection will catch the bottom before injury. Do not forget the issue of sharp edges on the rail. Now look at your edge protection requirements down the steps. We do not know where the grade is as you go down.

 

[Gene Boecker]

I just wanted to jump in and echo what Mark has noted from an accessibility standpoint. It is also important to note that the 12 inches plus a tread at the bottom only applied to those stairs to which the ADAAG is applicable. If the two levels are connected by ramps or elevators then the stairs do not need to meet the ADAAG criteria and the simple one tread extension is sufficient.

Also, Examiner hit the nail on the head regarding the protrusion design. Form what he is saying, FredK's comment about not complying may need a bit closer scrutiny. The fact that the vertical element is present accomplishes the cane detection as Examiner says. If the top is not more than 4 inches off from the cane detection zone, you should be good.

(But watch those sharp corners)