IBC & A117.1 Handrail Extensions

[tbz]

I have a fabricator with a project in which the design professional is wanting the handrail to change in direction around a corner per say.

I know we have covered this before here but I am starting a new thread just to keep it project specific to get your feedback.

I will explain more with each of the pics' as to code, to simplify we will start with assume 2018 IBC and later, and A117.1 of 2017 and later, I forgot to ask, but know it is likely 2021 or 2024 IBC, but nothing has really changed on this type of handrail termination between all 3-editions.

It is our interpretation, that there is no landing serving the change in direction in order to wrap 90 degrees to the right and continue down the edge of the 11-inch tread for 2 risers.

The landing would need to extend past the walls corner for the minimum stair width+ in order to provide for entrance from that direction for the handrail placement requested.

Please review and comment.

The fabricator provided the shop drawings showing the LT/Blue,

The designer wants the handrail to turn right, shown in green, and not follow the direction of travel.

The next pic shows the plan view.

The 3rd pic shows the ISO.

Thank you for the comments.

 

[Paul Sweet]

I think both rails need to go all the way down. The notch on the right looks like a tripping hazard if someone tried to walk around that side of the stair.

 

[Yikes]

You said 2018 IBC, so this is NOT inside a dwelling unit, correct?

 

[Yankee Chronicler]

The long rail -- the one on the left in the plan -- is correct as the fabricator submitted it, and cannot be done as the architect wants to do it. As you point out, there is no landing to accomplish the 90-degree change of direction. Worse, the natural direction of travel appears to be straight, in the direction of the stairway, so the architect's proposal would leave the last two risers with no handrail in the natural direction of travel.

Shifting to the right side of the stair -- again, after traversing the landing there are two more steps/risers, and they have no handrail at all on the right side.

IBC 2021:

[BE] FLIGHT. A continuous run of rectangular treads,
winders or combination thereof from one landing to another.

[BE] STAIR. A change in elevation, consisting of one or
more risers.

[BE] STAIRWAY. One or more flights of stairs, either
exterior or interior, with the necessary landings and platforms
connecting them, to form a continuous and
uninterrupted passage from one level to another.

So one riser constitutes a stair. The lower change of elevation incorporates two risers, so regardless of the plan configuration, it is a stair. BUT ... once you get far enough to the right to reach where the risers begin to curve in plan, the tread width no longer conforms to the uniformity criteria in the code, so that portion cannot be used as a portion of a means of egress. The right-hand handrail should extend to prevent occupants from straying onto the portion with non-uniform tread widths/depths.

1011.5.2 Riser height and tread depth. Stair riser
heights shall be 7 inches (178 mm) maximum and 4
inches (102 mm) minimum. The riser height shall be
measured vertically between the nosings of adjacent
treads. Rectangular tread depth shall be 11 inches (279
mm) minimum measured horizontally between the vertical
planes of the foremost projection of adjacent treads
and at a right angle to the tread’s nosing. Winder treads
shall have a minimum tread depth of 11 inches (279 mm)
between the vertical planes of the foremost projection of
adjacent treads at the intersections with the walkline and a
minimum tread depth of 10 inches (254 mm) within the
clear width of the stair.

1011.5.4 Dimensional uniformity. Stair treads and risers
shall be of uniform size and shape. The tolerance between
the largest and smallest riser height or between the largest
and smallest tread depth shall not exceed 3/8 inch (9.5
mm) in any flight of stairs. The greatest winder tread
depth at the walkline within any flight of stairs shall not
exceed the smallest by more than 3/8 inch (9.5 mm).

And finally:

1011.11 Handrails. Flights of stairways shall have handrails
on each side and shall comply with Section 1014.
Where glass is used to provide the handrail, the handrail
shall comply with Section 2407.

 

[tbz]

You said 2018 IBC, so this is NOT inside a dwelling unit, correct?

The location is in a lobby area in a university building I believe in VA.

I am not sure what is going on with the other side, I was told it is one of those large seating stair combination areas.

Thanks for the detailed response Yankee C.

I guess everyone had a 4-day week, enjoy the weekend.

Regards - Tom

 

[steveray]

I'd fail the light green

 

[Yankee Chronicler]

Allow me to play devil's advocate a bit:

Point 1: If the lower handrail were done as the architect wants to do it, that means the direction of travel down (or up) the stair will be parallel to that handrail. The lower step is barely large enough to qualify as a step -- maybe. The portion of the landing that turns the corner is a quarter circle -- there's nothing there to step on.

Point 2: The configuration shows two flights of stairs, with a landing. Stairs are required by code to have handrails on both sides. If the handrail turns around the corner as the architect wants it, then there has to be a second handrail parallel to that. Where's that going to go, and how much travel width can there possibly be between them?

 

[steveray]

that means the direction of travel down (or up) the stair will be parallel to that handrail. The lower step is barely large enough to qualify as a step -- maybe. The portion of the landing that turns the corner is a quarter circle -- there's nothing there to step on.

That would be my argument...

 

[tbz]

Morning All,

So a few more notes and a simple question.(s)

• So I am not sure that the tread section along the wall for the small flight qualifies for being a tread since it is not a minimum of 11 inches deep perpendicular to the leading edge. At that direction it is only a 8" tread depth per the first figures dimension notes.
• And if you do consider it a directional approach, as Y.C. notes that it needs to be the minimum stair width from that wall for that direction which it is not, even if you argued it was a winder tread, which again does not meet the minimum dimensions for a winder tread from that approach, the handrail would have to meet the minimum radius for the turn, which a hard 90 does not.
• As to the lower, missing handrail, I believe the designer is claiming that area on the other side of what I will call a funky floor step is assembly seating, and as thus does not need the 2nd handrail, not sure were that logic is comin in, but one thing at a time.

So, lets simplify the questions to a pass or fail at inspection.

1. Would you pass or fail the inspection for the 90deg turn as noted in green in figure 1 of post 1.
2. Would you pass or fail the inspection for no 2nd handrail on the lower flight.

I wont ask for explanations or code sections, a simple (1. F) or (1.P) and the same for #2 will serve its needs for this topic.

 

[Yankee Chronicler]

So, lets simplify the questions to a pass or fail at inspection.

1. Would you pass or fail the inspection for the 90deg turn as noted in green in figure 1 of post 1.
2. Would you pass or fail the inspection for no 2nd handrail on the lower flight.

I would fail both -- except that in my town it would never be inspected, because the design would have been rejected during the permit application plan review stage.

 

[steveray]

1. Yes fail
2. Yes fail..Or at a min. more info on assembly seating...

I was so busy looking at the number one that I missed the #2 below it...Always watch where you step...