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Exit access travel distance to enclosed 2hr staircase

eo_arch

Registered User
Joined
Jun 11, 2021
Messages
3
Location
Albany, CA
We are designing an addition for two residential units on a 120' deep lot, R3 occupancy, 2 stories (ground level is commercial space) with only one staircase. We exceed the 125' exit access travel distance limit, but we would like the make the case that the 125' exit access travel distance should be measured to the encloses, fire rated staircase. Anyone has any experience or knows of a code exception? Alternatively, we would like to propose/design the staircase to become an area of refuge. Would that be allowed? Thank you.
 
Exit access distance is measured from the most remote point of the space to the the exit - which is the fire-rated staircase. You will have to provide an exit passageway with the same rating as the stair enclosure if the stair doesn't discharge directly to the outside.
 
We are designing an addition for two residential units on a 120' deep lot, R3 occupancy, 2 stories (ground level is commercial space) with only one staircase. We exceed the 125' exit access travel distance limit, but we would like the make the case that the 125' exit access travel distance should be measured to the encloses, fire rated staircase. Anyone has any experience or knows of a code exception? Alternatively, we would like to propose/design the staircase to become an area of refuge. Would that be allowed? Thank you.
If it is an enclosed fire rated stair, that would be a protected pathway, which is considered the exit, thus when you arrive at the start of it within 125' you have met the requirements. Path of travel is measured diagonally down the stairs (not horizontally as in plan view).
 
IBC definition

EXIT. That portion of a means of egress system between the
exit access and the exit discharge or public way. Exit components
include exterior exit doors at the level of exit discharge,
interior exit stairways and ramps, exit passageways, exterior
exit stairways and ramps and horizontal exits.
 
If it is an enclosed fire rated stair, that would be a protected pathway, which is considered the exit, thus when you arrive at the start of it within 125' you have met the requirements. Path of travel is measured diagonally down the stairs (not horizontally as in plan view).
That is actually another question I had: how to measure path of travel on stairs. Is there a graphic explanation for that, somewhere? Thank you!!
 
That is actually another question I had: how to measure path of travel on stairs. Is there a graphic explanation for that, somewhere? Thank you!!

I d not think I ever measured travel distance on stairs,,, interesting

Maybe like this/:::::
 

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I d not think I ever measured travel distance on stairs,,, interesting

Maybe like this/:::::
That's great, thank you. The building official tells me my 2hr fire rated staircase doesn't count as an exit. Maybe because it ends in a lobby and not directly outside?
 
That's great, thank you. The building official tells me my 2hr fire rated staircase doesn't count as an exit. Maybe because it ends in a lobby and not directly outside?

yep unless that area to an exit has the same rating as the enclosure, or create an exit passage way

Or

when you exit the stair, you can see an exit directly in front of you
 
50% of your discharge can possibly not go to the outside...

1028.1 General. Exits shall discharge directly to the exterior
of the building. The exit discharge shall be at grade or shall
provide a direct path of egress travel to grade. The exit discharge
shall not reenter a building. The combined use of
Exceptions 1 and 2 shall not exceed 50 percent of the number
and minimum width or required capacity of the required
exits.
Exceptions:
1. Not more than 50 percent of the number and minimum
width or required capacity of interior exit
stairways and ramps is permitted to egress through
areas on the level of discharge provided all of the
following conditions are met:
1.1. Discharge of interior exit stairways and
ramps shall be provided with a free and
unobstructed path of travel to an exterior
exit door and such exit is readily visible
and identifiable from the point of termination
of the enclosure.
1.2. The entire area of the level of exit discharge
is separated from areas below by
 
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