Two Exits Required

[DTBarch]

Scenario: Existing 4-story office building in California has a single tenant occupying the entire 45,000sf 4th floor. 4th Floor has two Interior Exit Stairways serving the floor.

Tenant wants to give back 15,000sf of their space (area shaded red in image below). The "give back" space would be demised for future separate tenant, and we would create common area corridor access to the Elevator Lobby and one of the two multi-occupant restrooms on the floor.

At 15,000sf, the new tenant space functioning as a Business area per Section 1006.2.1 would require two exits or exit access doorways.

Question: Can the two exit access doors from the new 15,000sf suite, sufficiently separated, and both discharging into a common hallway with access to just one of the two interior exit stairways satisfy the requirement for the two exits? Both exit access doors would funnel into the single exit stairway.

 

[classicT]

No, the proposed future tenant will need two exits, as required per 1006.3.2. The key is in the definition of an exit.

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.

Each of the two interior exit stairways serve as an exit. If access is not provided to both, then you only have one exit. The only thing that another door out of the proposed tenant space provides is relief from a common path of egress travel.

 

[classicT]

To clarify, the two doors that you have labeled as "Exit Access Doors" are correctly identified as exit access doors (definition below). The key is in the fact that they do not constitute exits, as per the definition I previously posted.

EXIT ACCESS DOORWAY. A door or access point along the path of egress travel from an occupied room, area or space where the path of egress enters an intervening room, corridor, exit access stairway or ramp.

As mentioned in the previous post, Section 1006.3.2, particularly Table 1006.3.2 (below), will tell you that any occupancy three stories above grade plane or more will require access to at least two exits.

 

[e hilton]

If yo7 changed the red part of the floor to green where the label “exit acces door 2” is ... that gives both tenants access to both stairwells. On the right side of the building. Does that work?

 

[RLGA]

Another exit stair must be provided (an exit access stair to the 3rd story that will then allow access to the second enclosed stair) or there must be a public means of access to the other stairway without having to enter the other tenant's space. Two separate and distance means of egress must be provided to all occupants of that story per Section 1006.3.

The only thing that another door out of the proposed tenant space provides is relief from a common path of egress travel.

Actually, it doesn't. Because the two paths converge, and converging paths are not separate and distinct leading to two exits.

 

[cda]

Where is the elevator

 

[e hilton]

Where is the elevator

I see 7 on the floor, looks like at least 1 is freight. They are the white squares with the X. One in the lower right is grey, that’s probably the freight.

 

[Tim Mailloux]

No, the proposed tenant would only have access to one exit.

 

[DTBarch]

Appreciate the feedback as always. The verbiage that causes a pause is 1006.2.1 "Two exits OR exit access doorways from any space shall be provided..." but then further clarified in 1006.3 The existing tenant will likely need to allow for a corridor thru their space, OR the give back needs to shrink to accommodate an occupant load of 49

 

[RLGA]

Appreciate the feedback as always. The verbiage that causes a pause is 1006.2.1 "Two exits OR exit access doorways from any space shall be provided..." but then further clarified in 1006.3 The existing tenant will likely need to allow for a corridor thru their space, OR the give back needs to shrink to accommodate an occupant load of 49

Section 1006.2.1 is only for spaces...not stories; whereas, Section 1006.3 is specifically for stories.

Even if the tenant can reduce its occupant load to less than 50, Table 1006.3.2 states that a story with 1 to 500 occupants is required to have 2 exits or access to two exits. The latter part of my last sentence is why I stated previously that an exit access stair can be provided from the 4th story to the 3rd story as long as when they are on the 3rd story the occupants can reach that other exit stairway (not the same exit stairway they could have reached on the 4th story).

Further, a single exit is not permitted for Group B occupancies above the second story per Table 1006.3.3(2).

 

[classicT]

Appreciate the feedback as always. The verbiage that causes a pause is 1006.2.1 "Two exits OR exit access doorways from any space shall be provided..." but then further clarified in 1006.3 The existing tenant will likely need to allow for a corridor thru their space, OR the give back needs to shrink to accommodate an occupant load of 49

In agreement with Ron for the preceeding post.

Table 1006.3.3(2) is provided in post #3.

As mentioned in the previous post, Section 1006.3.2, particularly Table 1006.3.2 (below), will tell you that any occupancy three stories above grade plane or more will require access to at least two exits.

 

[DTBarch]

The latter part of my last sentence is why I stated previously that an exit access stair can be provided from the 4th story to the 3rd story as long as when they are on the 3rd story the occupants can reach that other exit stairway (not the same exit stairway they could have reached on the 4th story).

RLGA, correct me if I'm wrong, but they would still fall under the common path distance limitations and would need to include the route down the stair to the 3rd floor before they have a choice of 2 exits, therefore unfortunately not viable.

 

[DTBarch]

So revising my previous recap, since this is the 4th floor, there is no occupancy of any classification allowed, regardless of size or occupant load, that has access to only one exit, according to Table 1006.3.3(2). By continuation, this opens up another question as follows.

So assuming we need to create a common corridor access to both stairs, that opens up another question relative to this specific tenant space. You'll notice in the plan, there is a large training room (highlighted in yellow) with an occupant load of 167 occupants. This is obviously an Assembly occupancy, but is less than 10% of the floor, so it would be Accessory to the Group B primary occupancy classification.

Question: Does 2019 CBC Section 1029.3.1 apply to that training room, OR does the fact that it is Accessory to Group B provide an exemption?



This plays into whether the new corridor we have to create on this fully sprinkled 4th floor would need, at least a portion, to be of 1-Hour rated construction?

 

[steveray]

Interesting...We do not have that section....But my gut is , Yes, that would apply...per 508.2.1 (2015 IBC)

 

[ADAguy]

Great discussion and analysis gang!