egress stair: is a grand stair in the lobby qualifed as a means of egress?


Hi, all:

I need your big help here:

One friend of mine showed me his design for a small community center, roughly 7000 sqft with 2 stories. Although it looks great in the beginning, later I found out it only has one enclosed fire egress exit, another one is a grand stair from lobby to 2nd floor. He told me that stair to lobby is qualified as an means of egress since it directly connects to the lobby then go to outside.

My friend also told me the occupancy won't be larger than 100 most of time. GFA is around 7000 sqft. 4000 sqft for 1st, 3000 for 2nd floor.

I really doubted his understanding for that stair. The means of egress need an enclosed discharge to the outside, a grand stair is open to the lobby. if there is fire, the smoke could spread to everywhere. Please tell me I am right!

Nov 8, 10 11:56 pm
Le Courvoisier

I've always been told that if you enclose the lobby with an appropriately fire-rated enclosure then you can use it as an egress.

Nov 9, 10 2:03 am

if the grand stair is open then no, it cannot be a means of egress...

the stair itself needs to be in a continuous fire rated enclosure, in which case you can usually make use of an exception to be allowed to have one of your means of egress discharge at grade level into the lobby, as long as you have a second stair that discharges through a continuous fire rated enclosure to the exterior of the building at grade... in order to have one of your means of egress exit through the lobby, it needs to be fully sprinklered and you need a continuous fire rated separation between the lobby and any level below it...

Nov 9, 10 2:30 am

bRink is right, i believe.

If this question comes up on the licensing exam, by the way, just put in two fully enclosed stairs at totally opposite ends of the building PLUS the lobby stair. There's no room for nuanced code interpretations on the exam.

Nov 9, 10 7:52 am

agreed... bRink is correct... i've worked on a recreation center with this exact circumstance, although the building was quite a bit larger than the one in question here... essentially any open, monumental stair is non-existent as far as code is concerned...

it may be possible if the lobby is fully enclosed, but it would probably just be cheaper to throw in a standard, cheap fire stair...

Nov 9, 10 8:57 am

bRink and others:

Just want to clarify, so you mean my friend can do it as long as the lobby is fully sprinkled and there is a continuous fire rated separation between lobby and one level below it( basement?)?

Does he need to put a fire rated separation between lobby and second floor?

I checked NFPA101 v2009, in chapter 7(means of egress) and chapter 12(new assembly occupies). None tells me there is an exception to allow a grand stair to be qualified as an means of egress stair. Could anyone double check it with me?

I believe NFPA is precede than IBC, so I use NFPA current version.

Nov 9, 10 10:09 am

No, the IBC says that exit stairs must be in a fire rated enclosure and discharge to the exterior at grade.

1. Up to 50% of your required egress width can exit through a space (your lobby) at grade if that space is fully sprinklered and fire separated from the level below...
2. If you had a corridor that maintains a continuous fire separation from the stair to exterior- needs to maintain at minimum the same fire rating as the stair, that works as well... If you have a monumental stair that is open, the IBC does not expressly allow for that as an egress...

Nov 9, 10 11:03 am

Also there is an exception where you can have the stair exit through a vestibule but there are dimensional limits to that I believe...

Nov 9, 10 11:05 am

You should actually see what jurisdiction you are in and review the code specific to the jurisdiction... Although the purpose of the IBC is to establish a safety standard, most jurisdictions I've worked on use the IBC or something based on the IBC...

Nov 9, 10 11:16 am


I still don't quite get it. I also checked IBC too, as it noted in Exceptions, it seems IBC can allow my freind to design like that, but NFPA doesn't think it is legal.

To be short, includes all the exceptions, who is right? Me or my friend?

Nov 9, 10 11:18 am

Is the stair in a fire rated enclosure? In other words, does it have rated walls enclosing it? If so, it can exit through a lobby if that lobby is sprnklered and separated from below.

If the stair is not in a fire rated enclosure, if it is like a monumental open stair, it isn't counted by IBC as an egress stair... That is how I understand it, although I would read the code, don't trust a bunch of people on an Internet forum! ;-)

Nov 9, 10 11:25 am
timothy sadler®

2006 IBC - it's legal. There's an exception there that makes it so.
2009 IBC - that exception has been removed. Open stairs for egress not allowed.

NFPA 101 - They require a smoke wall, if I remember. Not all jurisdictions enforce the LSC, so your mileage may vary.

Nov 9, 10 12:39 pm

Here's one I saw the other day that had me scratching my head:

2 story mostly A3 building (9000 SF first floor, 5000 2nd), one fire stair, one non-egress monumental stair, and a second floor exit on to a non-combustible (but open) pedestrian bridge not at grade.

I keep meaning to dig through and see if there's any way the pedestrian bridge could be counted as a means of egress. I doubt it, but anyone want to chime in?

Nov 9, 10 1:05 pm
Distant Unicorn

Humorously enough, if there was a critical situation that required evacuation of the building... more than likely everyone will run to the grand staircase anyways as it is the biggest and most important psychologically.

Funny how this works out, no?

Nov 9, 10 1:25 pm

bRink: Thanks for your clarification.

OldFogey: That is a good and straight answer, thanks. Do you notice they mention it a 2-story building? Based on 2006 IBC, If a building with one story on the ground and one basement, the exception doesn't apply.

of course, this MAKEs sense. The basement requires stricter fire exit than the rooms on the ground.

Unicorn Ghost: I have same feeling too. But if there is smoke, people should run to the egress stair with Big red Exit on the top.

manamana: I think it doesn't apply to the code. But I would like to listen to others.

Nov 9, 10 1:54 pm

OldFogey: Did you check IBC 2009 Section 1016.1? I was told the exceptions are there.

Nov 9, 10 1:59 pm

I am wrapping up working on a project in NYC where the ornamental staircase was not eligible to be an egress stair. This building was 60 stories, and that is obviously different than your friends 2 story community center. But, I believe there has to be fire separation for a stair to be considered an egress stair.

Nov 9, 10 2:30 pm

The condition described by ARCHNME is still permitted for two story buildings with low hazard occupancies under 1020 and Chapter 7 of the IBC/CBC. No time to find the precise code section right now, but you'll need to read all the exceptions under the section on Vertical Exit Enclosures.

Nov 9, 10 3:35 pm

2006 IBC 1020.1 exception 8. we don't do 1009 IBC yet. For now, only one stair should need to be enclosed as long as only 2 are required. Of course your local authority having jurisdiction can interpret that however they choose.

Nov 9, 10 3:43 pm
timothy sadler®

archNRE: Section 1016.1 Exception 4 allows one to use an unenclosed exit access stairway in calculating exit access travel distance. I can calc travel distance down an open stair, but this section does not say that I can use an open stair as one of only two exit access stairs. If I have two enclosed stairs that actually count as 100% of my exit access, and a third, open stair that I also choose to use as an exit, I can calc travel distance dwon it.

The exceptions which used to exist to allow one to use an unenclosed stair as 50% of my building exit access doesn't seem to exist anymore. One of our primary parti's in medical is the medical office building with one enclosed stair and another open stair in an atrium. According to the 2009 IBC we can't do this anymore. If someone finds to the contrary I'm all ears.

Nov 9, 10 5:17 pm
won and done williams

not to be an ass, but how hard is it to pull out your ibc (or locally applicable code) and check the requirement? i don't know what the answer is off the top of my head, but i know how to look up the answer. by and large, building codes are pretty damn explicit, and this doesn't sound like an issue that would be up for much debate. let's try to be a little self-sufficient here.

Nov 9, 10 8:38 pm

Here is IBC. It says OK to take the grand stair in the lobby as a means of egress. As I posted previously, NFPA101 doesn't allow this to happen:

In IBC 2009, there is requirements for vertical exit enclosure:
1020.1 Enclosures required. Interior exit stairways and interior exit ramps shall be enclosed with fire barriers constructed in accordance with Section 706 or horizontal assemblies constructed in accordance with Section 711, or both. Exit enclosures shall have a fire-resistance rating of not less than 2 hours where connecting four stories or more and not less than 1 hour where connecting less than four stories. The number of stories connected by the exit enclosure shall include any basements but not any mezzanines. An exit enclosure shall not be used for any purpose other than means of egress.

8. In other than Group H and I occupancies, a maximum of 50 percent of egress stairways serving one adjacent floor are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Any two such interconnected floors shall not be open to other floors. Unenclosed exit stairways shall be remotely located as required in Section 1015.2.
9. In other than Group H and I occupancies, interior egress stairways serving only the first and second stories of a building equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Such interconnected stories shall not be open to other stories. Unenclosed exit stairways shall be remotely located as required in Section 1015.2.

Nov 9, 10 9:39 pm

Glad to see you got to the key provision - two story buildings are allowed to have unenclosed stairs if sprinklered.

Nov 9, 10 10:47 pm

I stand corrected... Two storey building... Is that true of IBC 2009 as well?

Good discussion by the way, we should do more of this kind of thing on archinect...

Nov 9, 10 11:14 pm

Will look it up later... By the way, anybody know where you can download a PDF copy of the IBC to a mobile device? I know there are torrents, but any site that is accessible from a smart phone?

Nov 9, 10 11:35 pm

has the individual states, But they seem to stay an edition behind

Nov 10, 10 1:14 am

manamana: Nice! That's an awesome link!

Going to add a couple building code editions to the iBooks and bookmark this one for sure!

Nov 10, 10 4:47 am
Jah is my Co-pilot

Also you can find a few code books here:

I also agree about having these discussions on archinect, they are incredibly helpful.

A forum about building codes can be found here, with good info:

Nov 10, 10 1:20 pm
olaf design ninja

Your jurisdiction decides which code supercedes which code....
In general if your city says IBC without revisions then go by that even if NFPA is referenced., because most likely the examiner is using what the city says to use.

AND IF ITS QUESTIONABLE, GRAY, OPEN TO INTERPRETATION FILE THE DAMN THING ALREADY... Quit dicking around burning up the fee discussing something that can be answered with a simple filing, so what if you objections, you may not who knows, you don't..

Nov 10, 10 7:29 pm

Or just communicate with the city...

Nov 10, 10 9:44 pm

I know this is an old post, but ArchNRE's comments re. the IBC 2009 seem wrong.  2009 has removed the exception.  also it's located in section 1022.1, not 1020...  Read the code!

Apr 8, 13 11:04 am

Opening this up yet again, since this is a top google result when looking for this problem...

IBC 2009 does still allow an open stair.  Terms have been redefined and things rearranged.  Open stairs are "exit access stairways" per 1016, exceptions 3 & 4.  Exit access stairways can be counted as an exit per 1021, exception 3.

Very helpful article to explain this is here:

Sep 9, 13 6:00 pm

Moberlin, and Al Godwin (author of the article on Exit Access Stairs.  It is awesome that I finally understand - now the how to get open stairs vs an atrium loop for travel distance for a business use to egress from the second story (sprinkler) space/building at 300 ft vs the loop of thinking it was an atrium which limited me to 200 ft.

thank you thank you !

I could not figure out how the ICC 2009 commentary was stating that we could have 4 open stairs per 1016 exception 4. (because I could not get past the atrium looping in the code research)..  issues between High-rise/multi story and "two story" buildings exiting safety. 

and the term "exit access Stair"  thank you for defining the terminology!!!! and the in English not code speak of the real world use.

These discussions are much appreciated, even if you have to read all the comments to understand the path traveled to the conclusion.

Apr 4, 14 9:13 am

Another important part of this connection LOOP is

Number of exits and Continuity section 1021.1

exception No. 3 which permits you to use exception 3 or 4 of 1016.1 

( I am guessing that "4" is the maximum number in the 2009 commentary - because of the table 1021.1, but I have not found why the commentary says up to 4 open stairs; referneced table says minimum so the myth still remains.)

Jun 18, 14 9:44 am

Late to the discussion, by a few years, but in case someone ever reads this, as the second floor is 3000sqft, it technically qualifies as a mezzanine and not an additional floor. You don't need a rated interior stair between a main floor and a mezzanine.

Aug 31, 16 9:50 am

No, it doesn't qualify as a mezzanine. 

A mezzanine can be no greater than 1/3, 1/2, or 2/3 of the floor area of the space in which they're located. All depends on which exceptions you can apply.

Mezzanines are also required to be open to the area they are connected to.  Again there are exceptions.  

You cannot just label any random space as a mezzanine.  Some building officials allow it, but they're not correct. 

Aug 31, 16 10:37 am

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