EXIT ACCESS STAIRS

[nealderidder]

I'm working on a presentation regarding Exit Access Stairs (EAS) and need your help to make sure I've got the details right. Ron G. has been trying to explain this to me for ten years now so this might take some work. I'm looking to create a definitive explanation of what's allowed/required/possible (and will share it). Thank you in advance for your help!

To get started - let's say I've got a 5-story office building (B) that requires two exits off each level which are provided by two properly separated Interior Exit Stairs (see attached diagrammatic section). I want to add an additional open stairway that connects all 5 stories. This stairway is not required for egress. Some questions about this hypothetical open stair:

1. Is it an EAS? CBC 1019.1 defines EAS as exit access stairways serving as an exit access component in a means of egress system... Is there a legit argument that the open stair is not a part of my egress system and thus not an EAS and thus section 1019 doesn't apply?

2. Related to #1 - Is it even possible to have this open stair if it is NOT an EAS? CBC 712 seems to imply that if I want this open stair it needs to be either:

• In an atrium (then it's not an open stair)
• Not connecting more than two stories and not thru a rated floor assembly (I'm doing both)
• An Exit Access Stair

It seems to me that if I want an open stair connecting more than two stories, that's not in an atrium, I can only do it with an EAS. And if it's an EAS it would then have to meet the requirements of 1019 regardless of whether or not I need it for my egress system. Sound correct so far?

 

[Plumb-bob]

Cool project.
Without delving into the code language, I would say that the occupants of the building cannot be expected to know which stair is designed as the exit access stair, so any stair provided should have the required characteristics.

 

[bill1952]

The answer I have gotten the stairs are required for egress for someone on the stairs. It's their only way out.

 

[TheCommish]

Does not seem to be permissible 2015 IBC

712.1.9 Two-story openings. In other than Groups I-2 and
I-3, a vertical opening that is not used as one of the applications
listed in this section shall be permitted if the opening
complies with all of the items below:
1. Does not connect more than two stories.
2. Does not penetrate a horizontal assembly that separates
fire areas or smoke barriers that separate
smoke compartments.
3. Is not concealed within the construction of a wall or
a floor/ceiling assembly.
4. Is not open to a corridor in Group I and R occupancies.
5. Is not open to a corridor on nonsprinklered floors.
6. Is separated from floor openings and air transfer
openings serving other floors by construction conforming
to required shaft enclosures.

 

[nealderidder]

Cool project.
Without delving into the code language, I would say that the occupants of the building cannot be expected to know which stair is designed as the exit access stair, so any stair provided should have the required characteristics.

Agreed that any stair would have to meet the requirements of CBC 1011 (not sure of the IBC section numbers) but does that make it a part of the means of egress? I'm pretty convinced that my point #2 in the original post is correct - If I want to put holes in the floor and a stair connecting more than two stories ,that stair needs to meet the requirements of an EAS regardless of whether or not it's an "additional" stair and not necessary to meet egress requirements.

 

[nealderidder]

Does not seem to be permissible 2015 IBC

712.1.9 Two-story openings. In other than Groups I-2 and
I-3, a vertical opening that is not used as one of the applications
listed in this section shall be permitted if the opening
complies with all of the items below:
1. Does not connect more than two stories.
2. Does not penetrate a horizontal assembly that separates
fire areas or smoke barriers that separate
smoke compartments.
3. Is not concealed within the construction of a wall or
a floor/ceiling assembly.
4. Is not open to a corridor in Group I and R occupancies.
5. Is not open to a corridor on nonsprinklered floors.
6. Is separated from floor openings and air transfer
openings serving other floors by construction conforming
to required shaft enclosures.

712.1.9 is specifically for two-story openings that are "not used as one of the applications specified in this section" What I'm talking about is one of the applications specified in this section, that section being CBC 712.1.12 Exit access stairways and ramps. And I'm talking about more than a two story opening so I don't think this section would apply to the condition posed.

 

[nealderidder]

The answer I have gotten the stairs are required for egress for someone on the stairs. It's their only way out.

Interesting, certainly makes sense. Seems like the answer to point #2 in the original post is - the proposed stair MUST be considered an EAS.

 

[Sifu]

I'm working on a presentation regarding Exit Access Stairs (EAS) and need your help to make sure I've got the details right. Ron G. has been trying to explain this to me for ten years now so this might take some work. I'm looking to create a definitive explanation of what's allowed/required/possible (and will share it). Thank you in advance for your help!

To get started - let's say I've got a 5-story office building (B) that requires two exits off each level which are provided by two properly separated Interior Exit Stairs (see attached diagrammatic section). I want to add an additional open stairway that connects all 5 stories. This stairway is not required for egress. Some questions about this hypothetical open stair:

1. Is it an EAS? YES CBC 1019.1 defines EAS as exit access stairways serving as an exit access component in a means of egress system... Is there a legit argument that the open stair is not a part of my egress system and thus not an EAS and thus section 1019 doesn't apply? NO

2. Related to #1 - Is it even possible to have this open stair if it is NOT an EAS? IT CAN ONLY BE AN EAS CBC 712 seems to imply that if I want this open stair it needs to be either:

• In an atrium (then it's not an open stair)
• Not connecting more than two stories and not thru a rated floor assembly (I'm doing both)
• An Exit Access Stair YES

It seems to me that if I want an open stair connecting more than two stories, that's not in an atrium, I can only do it with an EAS YES. And if it's an EAS it would then have to meet the requirements of 1019 regardless of whether or not I need it for my egress system. Sound correct so far? YES

I am not able to read the CBC, but in the IBC I think it may be permitted as an open exit access stair.

All stairs are part of the exit access, and therefore must comply with IBC 1019 (a stair in the exit access = exit access stair). Per 1019 if a stair doesn't meet one of the conditions of 1019.3, then it must be enclosed. Per 1019.3 #4, A 5 story, sprinklered B, with an opening meeting the size limitations, sprinkler spacing and having a draft curtain you can have the unenclosed exit access stair without story limitations as long as it is not a "required" MOE. If it were a required MOE, then the travel distance might indirectly impose a story limitation based on travel distance.

Disclaimer: I have to visit these sections often because every time I think I get it, I realize I might not.

 

[MtnArch]

I am not able to read the CBC, but in the IBC I think it may be permitted as an open exit access stair.

Sifu:

Go here (https://up.codes/codes/california) and you can view the Cali codes!

 

[Paul Sweet]

CBC 1019.3 exception 4:

"Exit access stairways and ramps in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1, where the area of the vertical opening between stories does not exceed twice the horizontal projected area of the stairway or ramp and the opening is protected by a draft curtain and closely spaced sprinklers in accordance with NFPA 13. In other than Group B and M occupancies, this provision is limited to openings that do not connect more than four stories."

Thanks for the link, MtnArch.

 

[Yikes]

Neal, in regards to your OP question #2:
That open stair cannot atmospherically interconnect all 5 stories as per your original sketch:



You could atmospherically interconnect any two floors, such as floors 1+2 and floors 3+4, like this:




I have also seen moveable firewalls (Won-Door or equivalent). The fire alarm activates the walls to move and close around the stairs on floors 3, 4, and 5, leaving only floors 1 and 2 atmospherically interconnected.
https://www.wondoor.com/cmsdocument...ire_Doors_Means-of-Egress_Reference_Guide.pdf

 

[bill1952]

I'm with yikes on this.

Interesting, in my area of expertise - auditoriums and stages - an auditorium with several balconies "technically" breaks the same rule. No one has ever called it out.

 

[TheCommish]

how is a balcony a floor or story?

 

[bill1952]

iirc, 4th balcony is entered from 7th or 8th floor.



There is the argument this is a one storey building. And stadiums with 4 or 5 or more decks are also one story. Seems like a stretch to me.

"STORY. That portion of a building included between the upper surface of a floor and the upper surface of the floor or roof next above"

Isn't the surface you walk on and seats are on "the floor"?

 

[Sifu]

The commentary to IBC 1006.3.1 uses the term "required" in the explanation for why a an exit access can't travel through more than 1 story. It goes on to say that it is important to consider where a stairway is part of the required ways off the floor. This is very similar to the discussion in 1006.3. The commentary to 1019.3 #4 again says that where an EAS serves as part of the required ways off the floor, then it cannot be used for more than one story per 1006.3.1.

It seems to me like we have code limiting exit access stairs to two story openings when required to be used as a way off the story, but when not one of the required ways off the floor, they can exceed that limitation to various extents when they met the various provisions of 1019.3.

The OP states that there are two interior exit stairs required and provided, and that the EAS is not a required way off the stories. So what am I missing?

 

[nealderidder]

The commentary to IBC 1006.3.1 uses the term "required" in the explanation for why a an exit access can't travel through more than 1 story. It goes on to say that it is important to consider where a stairway is part of the required ways off the floor. This is very similar to the discussion in 1006.3. The commentary to 1019.3 #4 again says that where an EAS serves as part of the required ways off the floor, then it cannot be used for more than one story per 1006.3.1.

It seems to me like we have code limiting exit access stairs to two story openings when required to be used as a way off the story, but when not one of the required ways off the floor, they can exceed that limitation to various extents when they met the various provisions of 1019.3.

The OP states that there are two interior exit stairs required and provided, and that the EAS is not a required way off the stories. So what am I missing?

Sifu - I'm interpreting the code the same way you are. If the EAS is part of the required MOE you can't travel through more than 1 story before reaching and exit (the phrase "travel through more than 1 story" isn't crystal clear either). But if it's not a required MOE and a B occupancy and meets the other requirements of 1019 Exception #4 I don't see a limit on the height.

 

[Sifu]

Commentary makes it clearer, but commentary has been known to not reflect the actual intent....but it is what I have to go on to aid in my understanding. Others will chime in and maybe help too.

 

[nealderidder]

Neal, in regards to your OP question #2:
That open stair cannot atmospherically interconnect all 5 stories as per your original sketch:

View attachment 10485

You could atmospherically interconnect any two floors, such as floors 1+2 and floors 3+4, like this:

View attachment 10486


I have also seen moveable firewalls (Won-Door or equivalent). The fire alarm activates the walls to move and close around the stairs on floors 3, 4, and 5, leaving only floors 1 and 2 atmospherically interconnected.
https://www.wondoor.com/cmsdocument...ire_Doors_Means-of-Egress_Reference_Guide.pdf

View attachment 10487

Yikes - I'm glad you weighed in, this is exactly the response I've gotten that I can't square with the code. I've done an AMMR and surrounded the opening with Won-Door and everyone seemed satisfied. But help me find the code provision that says I can't atmospherically connect all 5 stories in this situation. I've attached that building section again along with a plan view.

This is great feedback and very appreciated!

 

[nealderidder]

Commentary makes it clearer, but commentary has been known to not reflect the actual intent....but it is what I have to go on to aid in my understanding. Others will chime in and maybe help too.

I think what's confusing is the question - Is a stair that's not required in order to meet egress requirements still an exit access component in a means of egress system? Seems to me the answer is obviously yes, basically everywhere you can walk in a building is an exit access component. But then I read 1019.1 - Exit access stairways and ramps serving as an exit access component in a means of egress system shall comply... To me this implies that there may be a situation where an EAS doesn't serve as an exit access component. Why even put that language in there?

 

[Sifu]

I think what's confusing is the question - Is a stair that's not required in order to meet egress requirements still an exit access component in a means of egress system? Seems to me the answer is obviously yes, basically everywhere you can walk in a building is an exit access component. But then I read 1019.1 - Exit access stairways and ramps serving as an exit access component in a means of egress system shall comply... To me this implies that there may be a situation where an EAS doesn't serve as an exit access component. Why even put that language in there?

Agree, but not sure we can accept the implication. I don't know how any stair, anywhere, is not an exit access component.

 

[nealderidder]

Agree, but not sure we can accept the implication. I don't know how any stair, anywhere, is not an exit access component.

Agreed. I don't see how anyone could argue that a stair (any stair) that a human can use is not an exit access component. And the question about whether or not it's a required part of the MOE seems to boil down to CBC 1006.3.2 (the section about travel through more than one adjacent story). Since that is the section that taketh away what 1019 giveth.

Would love to see 1019 revised to include something like - EAS provided in addition to other exit access components that fully meet the egress requirements of the building or space... (yeah, awful language, I'm not a lawyer but you get it). And revise 1006.3.2 to include another exception for "EAS provided in addition to..."

I see maybe why that's not in the code, very tricky to word it. But like you said, the commentary gets a little more explicit about the difference between "required" and "not required." Even though it's still not crystal clear, it does juxtapose a "required" way off the floor (1006.3) with an "open exit access stairway" (1019) maybe implying 1019 is for EAS that are superfluous to the required egress?

 

[TheCommish]

Don't over analyze, the safest is not to connect more than 2 stories with a an open area stairway, designee it as an atrium and comply with those requirements.

 

[nealderidder]

Don't over analyze, the safest is not to connect more than 2 stories with a an open area stairway, designee it as an atrium and comply with those requirements.

Commish - appreciate your point but this is a hypothetical exercise. As I stated in the original post I'm trying to reach a conclusion on what's possible. When it comes to legal language I think in depth analysis is unavoidable. I'm not looking for the most conservative answer that wouldn't raise eyebrows anywhere. The idea that code will only allow two stories to be connected directly conflicts with the language in 1019 - In other than B and M occupancies, this provision is limited to openings that do not connect more than four stories - I do feel like I'm chasing my tail and wish 1006.3 (CBC) was clarified a bit...

 

[bill1952]

Theoretically then:

You can have a vertical opening for any two stories, with or without stairs.

You can have a vertical opening for stairs up to four stories with size limitation, sprinklers, and draft stops.

Not codified as such but probably you could go at least four, maybe more, if enclosed in a "shaft" composed of opening protectives, theoretically, if you can afford it.

I don't think the fact they are exit access stairs, required or not required, is a factor.