• Welcome to the new and improved Building Code Forum. We appreciate you being here and hope that you are getting the information that you need concerning all codes of the building trades. This is a free forum to the public due to the generosity of the Sawhorses, Corporate Supporters and Supporters who have upgraded their accounts. If you would like to have improved access to the forum please upgrade to Sawhorse by first logging in then clicking here: Upgrades

Dead end corridor within mixed occupancies

tuzi

Registered User
Joined
Jun 14, 2016
Messages
45
Location
Colorado
I have a floor plate with R2, S-2, and A-2. The aggregate area of S-2 and A-2 are over 10% of the floor plate. If I take the floor as un-separated occupancies, then I know I have to follow 20' dead end as A-2 is the more stringent. I am wondering if I separate A-2 from the rest of the floor with 1-hour fire barrier with 45 min. door, does it mean max. 50' dead end corridor for R-2 will apply or it's not the case unless aggregate area of S-2 and A-2 is under 10%?
 
If a corridor is serving an assembly occupancy, then you're limited to the 20-foot limit on dead-end corridors, regardless of whether or not the assembly occupancy is an accessory use. Accessory uses are still classified per the applicable occupancy group, the main exception is that you do not have to separate the accessory occupancies from the main occupancy, but all other code provisions applicable to those accessory occupancies are still required.
 
image.png

The corridor I circled only serves the R2, does it mean it could be max. 50 ft, although I have A-2 on this level?
 
The image didn't come through, but if the corridor is only serving the Group R, then yes, the longer distance for a dead end corridor would be permitted.
 
While waiting for the floor plan.

Where your concern is with the dead end,

Are you required two means of exit ??
 
Add a door across the corridor in the dead end.

Not sure if you put it on a mag door holder, if it is still legal????
 
Looks like as said by RGLA

Corridor used by assembly

20 ft max or widen the dead end portion
 
Yeah, I think I need to add the door.

Thanks, everybody for helps!


You know you can become a Sawhorse and support this great site

We have the unlimited plan, keep asking questions till you get an answer you like!!!
 
I assume the entire building is sprinkled so you get the 125 ft of common path of travel that would be permitted and not the 75 ft limit without sprinklers
 
I have a project with a very similar condition flagged in plan review. This thread has been very insightful - thank you.

One (possible) solution that has been proposed is a cross corridor door at the start of the dead end.

In another thread in this forum, there seems to be conflicting takes on whether a cross-corridor door may eliminate a dead end at all:
https://www.thebuildingcodeforum.com/forum/threads/dead-end-corridor.7049/

What I would propose: a cross corridor door on magnetic hold opens to close in a fire alarm event. On the pull side (the main corridor served by A occupancy) would be signs on each door leaf "NOT AN EXIT".

Unfortunately, the commentaries I have are silent on this kind of "creative" solution, and I found few mentions in a Google search on the issue. I'll soon be reaching out to the plan reviewer directly to discuss the issue, but I'm curious to know if the use of cross-corridor doors is really an acceptable solution.
 
If you are talking about a door across the corridor, to cut down on the dead end

That is allowed, as long as on the other side, you do not create an exiting violation.
 
Top