1009.2.1: Does roof deck require elevator as Accessible means of egress?

[Lorenbb]

Here's the situation: We have a four-story Type IIIB condo building under the 2015 IBC. Elevator served, with two interior exit stairs.

The top floor is the fourth story, which has two main types of spaces on it:
1. Enclosed residential spaces that are only the upper stories of multi-story dwelling units that have their accessible entries and spaces on the third story, and
2. A shared roof deck amenity, 100% open to the sky, with zero enclosed space. The roof deck is served by the stairs and the elevator.

The 2015 IBC text says "1009.2.1 Elevators required. In buildings where a required accessible floor is four or more stories above or below a level of exit discharge, not less than one required accessible means of egress shall be an elevator complying with Section 1009.4."

One of the exit stairs discharges at a basement level, so our fourth story is definitely "four ... stories above or below a level of exit discharge."

Does our required accessible roof deck trigger the need for an elevator with standby power for 1009.4?

I think it doesn't because:
1. The only real fourth story interiors are the not-accessible upper halves of the multistory dwelling units,
2. If the roof deck were on its own at this fourth story level (i.e., not sharing this level with the enclosed unit spaces), it clearly would not trigger 1009.2.1, because it would not be a story.

Am I wrong?

The challenge here is that we'd need a generator for standby power, and that is hard to work in on our site. Not to mention that it'd cost $.

Thanks for any opinions or guidance!

 

[RLGA]

What do you mean by "One of the exit stairs discharges at a basement level"? Is the basement really a basement? I can't see how a basement (as determined by the code) can be a level of exit discharge

 

[Mr. Inspector]

One of the exit stairs discharges at a basement level, so our fourth story is definitely "four ... stories above or below a level of exit discharge."

Is the roof less than 4 stories from the other stairway and elevator discharge level?

 

[RLGA]

Is the roof less than 4 stories from the other stairway and elevator discharge level?

Rick18071 has a point. The height element of the requirement is not based on the lowest level of exit discharge, but a level of exit discharge. If the first story is a level of exit discharge, then the elevator is not required to be an accessible means of egress. I assume the roof is required to have two means of egress, so either you have two stairs to the roof, or the elevator must become the second accessible means of egress, thus triggering the standby power requirement.

 

[Lorenbb]

What do you mean by "One of the exit stairs discharges at a basement level"? Is the basement really a basement? I can't see how a basement (as determined by the code) can be a level of exit discharge

Yes, of our sloped site, one of the exit stairs discharges at a level that is below the average grade plane, so I was calling that a basement. "daylight basement" might be a clearer term.

 

[Lorenbb]

Is the roof less than 4 stories from the other stairway and elevator discharge level?

Hmm, I had not been thinking of it in those terms.

One of the stairs discharges at L1, the other discharges below L1.

I was reading "four or more stories above or below a level of exit discharge" as talking about a story that is four or more stories above or below ANY level of exit discharge. And in this case our L4 is four stories above the lowest level of exit discharge.

But if I am reading that wrong, I am happy.

I'll dig into this more with the other office greybeards and the jurisdiction.

Thank you Rick18071 and RLGA, you are champs!

 

[RLGA]

Yes, of our sloped site, one of the exit stairs discharges at a level that is below the average grade plane, so I was calling that a basement. "daylight basement" might be a clearer term.

Then, technically, it is a story above grade plane if the next floor above is either more than 6 feet above the grade plane or more than 12 feet above finished ground level at any point. However, if the now second story is also a level of exit discharge, then that can be used and not the "basement."