# CORRIDOR vs BLDG Lobby



## alexq (Oct 25, 2017)

Thanks for viewing:
I am designing a remodel for a lobby of a 27 story building built in 1953 (non-sprinklered). The main entrance/exit I am moving over 1 structural bay.  Existing entrance is all non-rated glass doors and windows. There is also a secondary exit in the back via a fire-separated passageway. 

The plan reviewer is commenting that the entire ground-level lobby space is considered a *corridor *_a_nd should therefore be 1 hour rated everywhere, including the entrance doors and windows. This would make for an expensive and unsightly door/window assembly.  I believe that the lobby space should not be considered a corridor, but rather an assembly space. 

Please let me know if you know otherwise. See image here: https://ibb.co/fy79T6

*Thanks,*
Alex


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## steveray (Oct 25, 2017)

What level of alteration is it?


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## alexq (Oct 25, 2017)

steveray said:


> What level of alteration is it?


Steveray: Level 2 alteration.  2015 building code.


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## ADAguy (Oct 25, 2017)

As an assembly space what advantage do you gain, they must be protected too?


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## mark handler (Oct 25, 2017)

And what assembly function would it be per chapter three definitions? A-1, A-2, A-3, A-4 or A-5?
Look at the descriptions.
What function would it be?


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## alexq (Oct 25, 2017)

ADAguy said:


> As an assembly space what advantage do you gain, they must be protected too?


You are right - having a 1 hour rated interior is not a problem.  The problem is the main entrance to the building.  The reviewer wants this main entrance (all glass) to be rated as well.


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## alexq (Oct 25, 2017)

mark handler said:


> And what assembly function would it be per chapter three definitions? A-1, A-2, A-3, A-4 or A-5?
> Look at the descriptions.
> What function would it be?


The building is a B occupancy (office building) but the lobby of it would be an ASSEMBLY WITHOUT FIXED SEATS, unconcentrated per Table 1004.1.2


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## cda (Oct 25, 2017)

If it is an exterior wall 

Per corridor should not have to be rated

Is there another reason to rate it?? Distance to a building , property line other ??


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## alexq (Oct 25, 2017)

cda said:


> If it is an exterior wall
> 
> Per corridor should not have to be rated
> 
> Is there another reason to rate it?? Distance to a building , property line other ??


Thanks!  Exactly what I thought. Can you please direct me to where it says this in the code?  I am looking through section 708 and 1020.1..


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## cda (Oct 25, 2017)

Not going to be 1020

It is the code of common sense IBC section use your head 

That is not directed at you 

Just like if you have a rated enclousure, the doors in it have to be rated,,, till you hit the bottom extrerior door, than it does not have to be rated.

There are a few smarter people on here that will explain it better.


Maybe if that person has a boss talk to them.
Hopefully it is not a one horse town


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## cda (Oct 25, 2017)

Just saw is this actually in dallas city??


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## mark handler (Oct 25, 2017)

alexq said:


> The building is a B occupancy (office building) but the lobby of it would be an ASSEMBLY WITHOUT FIXED SEATS, unconcentrated per Table 1004.1.2


WHAT ASSEMBLY USE?


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## Yikes (Oct 25, 2017)

cda said:


> Not going to be 1020



How about 1020.1 exception #5:

SECTION 1020
CORRIDORS
1020.1 Construction. Corridors shall be fire-resistance rated in accordance with Table 1020.1. The corridor walls required to be fire-resistance rated shall comply with Section 708 for fire partitions.
*Exceptions:*​*5.* *Corridors adjacent to the exterior walls of buildings shall be permitted to have unprotected openings on unrated exterior walls* where unrated walls are permitted by Table 602 and unprotected openings are permitted by Table 705.8.


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## Francis Vineyard (Oct 25, 2017)

Yikes said:


> How about 1020.1 exception #5:
> 
> SECTION 1020
> CORRIDORS
> ...


That's the answer


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## cda (Oct 25, 2017)

Yikes said:


> How about 1020.1 exception #5:
> 
> SECTION 1020
> CORRIDORS
> ...




BINGO

Guess I should read that darn book


I new there were smarter people than I or is it me.


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## RLGA (Oct 25, 2017)

I read this before going into teaching my class and didn't have time to respond, but now I'm looking at it, and Yikes has nailed the answer.


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## Francis Vineyard (Oct 26, 2017)




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## alexq (Oct 26, 2017)

Yikes said:


> How about 1020.1 exception #5:
> 
> SECTION 1020
> CORRIDORS
> ...



Thank you very much -  appreciate it.


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## steveray (Oct 26, 2017)

Somehow missed the "exterior wall" piece the first time...Agree with Yikes


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## alexq (Oct 26, 2017)

Thank you all for your responses. 
- Alex


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