# Spaces with one exit on the 4th floor



## nealderidder (Jan 10, 2018)

I'm having a disagreement with a colleague and I want you all to prove me right!

We're in California (based on 2015 IBC). My contention is that any space you put on the 3rd floor (or above) of a building will require two exits regardless of occupant load or anything else.

The only exception is for R2 (4 units max.) and R3 which can go up to the 3rd (R2) or 4th (R3) floor and have only one exit.

Table 1006.3.2(1) seems pretty black-and-white to me. Am I right?

Thanks.


----------



## RLGA (Jan 10, 2018)

You are right.

Unless the "3rd floor" can be considered a mezzanine, a 3rd floor and above must have two exits or access to two exits (i.e., exit access stairs or ramps). Table 1006.3.2(2) is very clear: third story and above is not permitted in any occupancy (except for Group R-2, as you indicate, under certain conditions).

Section 1006.3.1 clearly states that "Each story" shall have the number of exits specified in Table 1006.3.1, which requires two exits or access to two exits on any story when the occupant load is 1-500. It further states that a single exit is permitted in accordance with Section 1006.3.2, which references the two tables regarding single exits.


----------



## nealderidder (Jan 10, 2018)

Love it when I'm right. 

Thanks Ronald.


----------



## TheCommish (Jan 11, 2018)

it is not about being right, IMHO it is about comply with the code

see signature below


----------



## kilitact (Jan 11, 2018)

Unless, think daylight.

Rooms, areas and spaces with exits that discharge directly to the exterior at the level of exit discharge, are permitted to have one exit.
.


----------



## mtlogcabin (Jan 11, 2018)

nealderidder said:


> My contention is that any space



I disagree that any space  within a story would require two exits. Example a 10' X 10' office space or a conference room with an occupant load of less than 50 would not require two exits just because it is on the 3rd story or higher.
The story requires two exits not each space within the story


----------



## ADAguy (Jan 11, 2018)

I believe a mezzanine is not a "story", it is a level within the clear height of a story.


----------



## nealderidder (Jan 11, 2018)

mtlogcabin said:


> I disagree that any space  within a story would require two exits. Example a 10' X 10' office space or a conference room with an occupant load of less than 50 would not require two exits just because it is on the 3rd story or higher.
> The story requires two exits not each space within the story


--------------

Agreed, I didn't word that very well. My contention was that if you take a two story building and put any space on top of it, other than residential, that two exits would be required from that third story. This is true regardless of what you put on that third floor, what occupancy it is (except residential) or what occupant load it has.

That 10x10 meeting room would basically trigger the requirement for a second exit stair (in the particular case we were disagreeing on).

Thanks for the input!


----------



## tmurray (Jan 16, 2018)

What about rooftop mechanical room? Is single exit acceptable there?


----------



## mtlogcabin (Jan 16, 2018)

Depends
Some mechanical equipment and electrical equipment sizes will require two exits from the mechanical room. 
Only one exit would be required from the roof


----------



## Rick18071 (Jan 16, 2018)

I would not consider a mechanical room an occupied room.

Look up definition of "Means of Egress"

The NEC might require two exits from an electrical room.


----------



## SF arch (Feb 14, 2018)

I have a very similar Code issue (but it is under the 2013 CBC) with a 4 story, 3-unit building with two, 2-story units at the top two floors each with access to a main enclosed stair to the street. And one flat below those (on the 2nd floor) all over a parking level. However, the 2-story units are entered at the 4th floor and farthest travel is right on the 125 foot limit. Plan checker is saying no, two exits required.  And he is referencing a Code commentary for either 1021.2 or 1015.1 that says this layout is limited to three floors.  Can't find the commentary on that, Does anyone have a reference to that or reasons that this is or is not OK?


----------



## mtlogcabin (Feb 15, 2018)

Rick18071 said:


> I would not consider a mechanical room an occupied room.



2012 IBC
1015.3 Boiler, incinerator and furnace rooms.
Two exit access doorways are required in boiler, incinerator and furnace rooms where the area is over 500 square feet (46 m2) and any fuel-fired equipment exceeds 400,000 British thermal units (Btu) (422 000 KJ) input capacity. Where two exit access doorways are required, one is permitted to be a fixed ladder or an alternating tread device. Exit access doorways shall be separated by a horizontal distance equal to one-half the length of the maximum overall diagonal dimension of the room.


----------



## cda (Feb 15, 2018)

SF arch said:


> I have a very similar Code issue (but it is under the 2013 CBC) with a 4 story, 3-unit building with two, 2-story units at the top two floors each with access to a main enclosed stair to the street. And one flat below those (on the 2nd floor) all over a parking level. However, the 2-story units are entered at the 4th floor and farthest travel is right on the 125 foot limit. Plan checker is saying no, two exits required.  And he is referencing a Code commentary for either 1021.2 or 1015.1 that says this layout is limited to three floors.  Can't find the commentary on that, Does anyone have a reference to that or reasons that this is or is not OK?




Can you provide a link to the CBC


----------

