Spiral Staircase as Design Element vs. MOE

[Gutt Mcdonald]

I am working on an assembly space with 1 story above grade and a basement level within a mall. The basement level requires only 1 means of egress, which is provided and meets capacity req's. The client/designer are proposing a spiral staircase from the first floor to the basement- it will not be a required means of egress, and cant act as one if it would be needed. Can they place it in the space as a design element and should I be meeting chapter 10 of the IBC for this non-egress element?

 

[bill1952]

I have faced this several times. The answer I usually accept is that for someone on the spiral stair, the spiral stair is the m.o.e.

Not saying I agree or think you should not allow it, only that it's undeniably true. If only decorative, would the agree to a 42" barrier at top and bottom?

 

[Sifu]

 

[Paul Sweet]

You might be able to request a modification if the spiral stair meets 1011.10 and serves 5 or less people. It would be good to put an exit sign near the stair with arrows pointing towards the required means of egress.

 

[tbz]

The question I always pose to the design team is, why are you looking to have this space saving spiral stair case?

The answer they always give 95% of the time is to provide a convenient and quick access and save space.

So this is the route that they will use most of the time?

And you don't want it to meet the minimum the code requires?

I normally end with, your insurance carrier must love you.....

 

[Gutt Mcdonald]

Thank you all!
@bill1952, thats my line of thought, essentially a staircase provides a MOE by definition so long as said-staircase is one that that a human can tread on and go from one story to another.
Does that mean that it would be nearly impossible in a commercial space for a decorative staircase (spiral) that someone can say, well this staircase is serving as a design element only and Ill put signs noting "this is not an exit" (which ironically may take away any decorative ambience from the stair)
@tbz I like your thoughts- pretty good on the insurance! Only in this case, all required moe are met, and the client had originally intended a slide connecting 2 stories and then decided to pursue a spiral stair case instead...

 

[Gutt Mcdonald]

Hi all,
I'm at this again as Ive found the following wording in the IBC with Commentary-21 §1011.10 Spiral stairways
"Spiral stairways may be used in any occupancy as long as such stairways are not a component of a required means of egress"
@Sifu Is this a contradiction to what they put in the commentary in 1011.1 that youve posted- meaning this definitely is along the path of exit- again, by default.

 

[bill1952]

Where is basis for that staff opinion in the code?

 

[steveray]

I might be able to get on board with it…what are you doing in the basement? How big is the basement? And how are you handling the 2story opening?

 

[Sifu]

I don't see that language in the '21 commentary that I have on the ICC premium access. The '18 and '24 codes and commentaries are the same or similar. Where does that language come from?

One could say that a spiral stair can only be used as a component of a means of egress (required or not) only if the specific conditions provided exist. So unless the basement is limited 250sf² it would not meet the language of the code to use it at all. Once could say that if there is only one required MOE, and it is provided on an otherwise code compliant, non-spiral stair, then it could be allowed as a 2nd, non-required MOE based on the commentary you posted. I would not on a purely code compliance/prescriptive basis since the code seems pretty clear.

FWIW, the commentary in the '21 does not contradict the '21 code, it only "explains" it (the version I have). I only look for explanations when I don't understand the code language, which seems like understandable language to me.

 

[Yankee Chronicler]

The following is from the 2021 IBC Commentary (the book, not the ICC web site):

It is important for stairway safety that all stairways meet
the provisions in this section. This would include all elevation
changes using stairways: everything from one
riser to multiple flights and landings between stories
(see the definitions for “Stair” and “Stairway” in Chapter
2). These provisions will be applicable for interior exit
access stairways, interior exit stairways and exterior
exit stairways, as well as any steps along the paths for
exit access or exit discharge. It is intended that this
section be applicable to required stairways as well as
what can be called “convenience” stairways.

Sections 1011.2 through 1011.13 provide criteria for
the typical stairway. Special provisions are provided for
curved stairways (Section 1011.9), spiral stairways
(Section 1011.10), and stairways to the roof for fire
department access and for elevator equipment service
(Sections 1011.12 and 1011.12.1).

So, now we look at 1011.10:

1011.10 Spiral stairways. Spiral stairways are permitted to be
used as a component in the means of egress only within dwelling
units or from a space not more than 250 square feet (23 m2)
in area and serving not more than five occupants, or from technical
production areas in accordance with Section 410.5.

A spiral stairway shall have a 63/4-inch (171 mm) minimum
clear tread depth at a point 12 inches (305 mm) from the narrow
edge. The risers shall be sufficient to provide a headroom
of 78 inches (1981 mm) minimum, but riser height shall not be
more than 91/2 inches (241 mm). The minimum stairway clear
width at and below the handrail shall be 26 inches (660 mm).

Commentary on 1011.10:

Spiral stairways can be used within individual dwelling
units, from small spaces in other occupancies and
from technical production areas in spaces such as theaters.
Spiral stairways are also permitted: where specifically
indicated, such as to provide access between
the levels within a live/work unit (see Section 508.5.5);
within staff locations, such as serving guard towers in
jails (Section 408.3.4); and technical production areas
(Section 410.5.3.4).
...

Since the basement area in the original question has a compliant means of egress and only one MOE is required, that would make the proposed spiral staircase a convenience stair. What's the area of the basement space, and what's the occupant load of the basement space?

Also, what's the use/occupancy of the basement space, and what's the use/occupancy of the first floor space into which the spiral stair will open? The spiral stair will be creating a horizontal opening in the floor. How will that opening be protected?

 

[bill1952]

Since the basement area in the original question has a compliant means of egress and only one MOE is required, that would make the proposed spiral staircase a convenience stair.

Where is a "convenience stair" referenced in the code? And, as staff has pointed out to me, where is the 'compliant means of egress" when you are in middle of spiral stair?

 

[tmurray]

The larger problem is how are the general public to know that non-compliant elements should not be used in an emergency.

The public are largely incapable of understanding what is "safe" and what is not based on a casual inspection, especially during an emergency. Do we really expect them to stop and read signs when the building is on fire?

 

[Yankee Chronicler]

Where is a "convenience stair" referenced in the code? And, as staff has pointed out to me, where is the 'compliant means of egress" when you are in middle of spiral stair?

The term is not used in the IBC, but it is widely used in the design professions and code community, at least in this part of the country. The term is used in the IBC Commentary (I quoted it). The Commentary basically supports what has always been taught (around here) regarding the code: Stairs are only addressed in Chapter 10, so Chapter 10 applies to all stairs, whether or not they are required means of egress.

I don't like it. It's a lazy, sloppy way to write a code and I suspect if it were ever challenged by a good lawyer there would be ramifications. But I'm not aware of anyone having challenged it. The basic argument is that the code addresses stairs as "means of egress," not solely as "required means of egress." Since any stair may be used for egress ==> it's covered.

 

[bill1952]

The term is not used in the IBC, but it is widely used in the design professions and code community, at least in this part of the country. The term is used in the IBC Commentary (I quoted it). The Commentary basically supports what has always been taught (around here) regarding the code: Stairs are only addressed in Chapter 10, so Chapter 10 applies to all stairs, whether or not they are required means of egress.

I don't like it. It's a lazy, sloppy way to write a code and I suspect if it were ever challenged by a good lawyer there would be ramifications. But I'm not aware of anyone having challenged it. The basic argument is that the code addresses stairs as "means of egress," not solely as "required means of egress." Since any stair may be used for egress ==> it's covered.

I think you made my point. No such thing as a convenience stair in IBC. I'm not advocating pro or con, just looking at the code.

Quite a while ago I submitted a proposal that said something to the effect that MOE elements not required for egress do not have to comply with the requirements. It failed rather quickly but following publication and the hearings I received calls and email from code officials all over US in support. Might be time to try again. (I think it began wanting to add a door purely for convenience that could only be 24 in he's wide.)

 

[steveray]

I think you made my point. No such thing as a convenience stair in IBC. I'm not advocating pro or con, just looking at the code.

Quite a while ago I submitted a proposal that said something to the effect that MOE elements not required for egress do not have to comply with the requirements. It failed rather quickly but following publication and the hearings I received calls and email from code officials all over US in support. Might be time to try again. (I think it began wanting to add a door purely for convenience that could only be 24 in he's wide.)

Please don't.....This will effectively eliminate sliding and other "doors" that are not really used for egress (think the restaurant that opens to the sidewalk in nice weather).....There is a time and a place for doors and stairs that don't need to meet egress requirements...It is our judgement and I am way OK with that....

 

[bill1952]

I'm saying not required on not required moe. That was like 2006?

I do think it should be clear. I know building officials are not concerned with consistency outside of their jurisdiction but as a designer, I do.

 

[Yankee Chronicler]

I do think it should be clear. I know building officials are not concerned with consistency outside of their jurisdiction but as a designer, I do.

As both a licensed architect and a licensed building official, I have to take exception to this statement. Of course building officials are concerned with consistency [in the codes]. Architects have to design to the codes and building officials have to review and inspect to the same codes. If something isn't clear and consistent to the architect, that same thing isn't clear and consistent to the building officials (and fire marshals). Consistency and clarity in the codes is VERY important to building officials. We hate it when a fuzzy section of the code results in a urination contest between the design professional(s) and the code official(s). In my home state, such disputes have to be submitted to the State for resolution. Regardless of the State's determination, that takes time, which delays approval of the permit.

 

[Gutt Mcdonald]

I don't see that language in the '21 commentary that I have on the ICC premium access. The '18 and '24 codes and commentaries are the same or similar. Where does that language come from?

One could say that a spiral stair can only be used as a component of a means of egress (required or not) only if the specific conditions provided exist. So unless the basement is limited 250sf² it would not meet the language of the code to use it at all. Once could say that if there is only one required MOE, and it is provided on an otherwise code compliant, non-spiral stair, then it could be allowed as a 2nd, non-required MOE based on the commentary you posted. I would not on a purely code compliance/prescriptive basis since the code seems pretty clear.

FWIW, the commentary in the '21 does not contradict the '21 code, it only "explains" it (the version I have). I only look for explanations when I don't understand the code language, which seems like understandable language to me.

https://docs.google.com/document/d/1WFTTk5FQuaHs1cuhuOrmZqDPkNimL4_0_dJFVY922Y0/edit?tab=t.0

Im unsure how to attach an image, let me know if this works.
The basement is larger than 250 SF, the required means of egress are met and this stair would only be provided as an additional stair- call it design, which ultimately is used as convenience by people present . (As in if you were standing in a shoppe that had an open stairs to a mezzanine level, in emergency no one would look out for the enclosed (required) MOE, they would utilize the open staircase) With that said, the stair would have signage noting it is not an exit and directing people to the correct exit. The stairs would comply with 1011 because it does need to be regulated even with it not being a required MOE- as is noted in the code.
The commentary on 1011 is referring to its commentary on 1011.5.3....

 

[Gutt Mcdonald]

I think you made my point. No such thing as a convenience stair in IBC. I'm not advocating pro or con, just looking at the code.

Quite a while ago I submitted a proposal that said something to the effect that MOE elements not required for egress do not have to comply with the requirements. It failed rather quickly but following publication and the hearings I received calls and email from code officials all over US in support. Might be time to try again. (I think it began wanting to add a door purely for convenience that could only be 24 in he's wide.)

But of course you do need to provide some level of safety as the component is utilized by occupants when all is said and done. In an emergency whose to start showing people to the "proper" or "required" MOE?
With that noted, I would opinion that all should comply with a "stair" or "door" etc section, and the required ones need comply with all sections applicable.
You can note the wording in ramps say, where the code notes if its an element of the required means of egress or just another ramp provided.

 

[Gutt Mcdonald]

The term is not used in the IBC, but it is widely used in the design professions and code community, at least in this part of the country. The term is used in the IBC Commentary (I quoted it). The Commentary basically supports what has always been taught (around here) regarding the code: Stairs are only addressed in Chapter 10, so Chapter 10 applies to all stairs, whether or not they are required means of egress.

I don't like it. It's a lazy, sloppy way to write a code and I suspect if it were ever challenged by a good lawyer there would be ramifications. But I'm not aware of anyone having challenged it. The basic argument is that the code addresses stairs as "means of egress," not solely as "required means of egress." Since any stair may be used for egress ==> it's covered.

I agree with that in principle however the wording of the code is rather convoluted in this regard.

 

[Gutt Mcdonald]

But of course you do need to provide some level of safety as the component is utilized by occupants when all is said and done. In an emergency whose to start showing people to the "proper" or "required" MOE?
With that noted, I would opinion that all should comply with a "stair" or "door" etc section, and the required ones need comply with all sections applicable.
You can note the wording in ramps say, where the code notes if its an element of the required means of egress or just another ramp provided.

Here is the wording from the IBC to back this up
"
1011.1 General. Stairways serving occupied portions of a
building shall comply with the requirements of Sections
1011.2 through 1011.13. Alternating tread devices shall
comply with Section 1011.14. Ship’s ladders shall comply
with Section 1011.15. Ladders shall comply with Section
1011.16."
To say, all occupied portions must comply regardless of if it is a required means of egress or not.

 

[Yankee Chronicler]

I've been doing this for about 55 years. Stairs have always been in the chapter on means of egress, and somehow architects and building officials have mnanaged to deal with convenience (non-required) stairs for at least that long. I don't think the code needs to be revised.

 

[steveray]

We need to do the same thing we did for doors:

1010.1​

Doors in the means of egress shall comply with the requirements of Sections 1010.1.1 through 1010.3.4. Exterior exit doors shall also comply with the requirements of Section 1022.2. Gates in the means of egress shall comply with the requirements of Sections 1010.4 and 1010.4.1. Turnstiles in the means of egressshall comply with the requirements of Sections 1010.5 through 1010.5.4.

Doors, gates and turnstiles provided for egress purposes in numbers greater than required by this code shall comply with the requirements of this section.