Exit from 2nd floor B Occupacy

[Timothy M. Stone]

All,
My question is this, I have a 2story B occupancy,
•first floor is 2,000 s.f.,
•2nd floor is 1,560 s.f.,
• there is one open stair, which creates a 2story ceiling @ first floor
• stair meets 2015 IBC 1019, item 1 as exit access stair
•there is on vestibule on 1st floor which meets icc
• there is one exit door out of the building per IBC 1004.1.1.3, and max occupant load on first floor is 30
and on 2nd floor is 25, i am thinking per IBC table 1006.2.1 I am permitted to exit all occupants out this one door or am i wrong about this?
in my mind I am trying to understand the difference btwn, table 1006.2.1 & table 1006.3.2?
in my mind i, i have one exit, and one exit stair, but im interpreting the code as I use table 1006.3.2 when I have multiple tenants on 2nd floor,
Please help,
Thank you,

 

[cda]

Welcome

You do know it is Friday

 

[cda]

Great info provided


2015 ibc

 

[cda]

2012 commentary if you do not have one

I doubt if wording for your sections has changed

http://diberville.ms.us/home/wp-con...C-Code-And-Commentary-Volume-I_Compressed.pdf

 

[Francis Vineyard]

Welcome Mr Stone and hope you enjoy the weekend.

Table 1006.2.1 is applicable from spaces though it does correspond with Table 1006.3.2 (2) for stories, in accordance with section 1006.1 the instruction is to use Table 1006.3.2 for Group B

Clearly when the occupant load exceeds 49 the 2 exits are required to meet 1007.1.1 and door swing with 1010.1.2.1

To allow both stories to discharge through a single exit will have to construct an exit enclosure with fire barriers in accordance to section 1023.2.

Note the exception to 1028 permits the vestibule to be constructed as fire partitions and not allowed in single exit buildings.

The thing that confuses me with Tables 1006.3.2 is why the term Common Path instead of Exit Access (2012 Tables 1021.2)?

Hate typing with an Android!

 

[Timothy M. Stone]

Welcome Mr Stone and hope you enjoy the weekend.

Table 1006.2.1 is applicable from spaces though it does correspond with Table 1006.3.2 (2) for stories, in accordance with section 1006.1 the instruction is to use Table 1006.3.2 for Group B

Clearly when the occupant load exceeds 49 the 2 exits are required to meet 1007.1.1 and door swing with 1010.1.2.1

To allow both stories to discharge through a single exit will have to construct an exit enclosure with fire barriers in accordance to section 1023.2.

Note the exception to 1028 permits the vestibule to be constructed as fire partitions and not allowed in single exit buildings.

The thing that confuses me with Tables 1006.3.2 is why the term Common Path instead of Exit Access (2012 Tables 1021.2)?

Hate typing with an Android!

• in my mind I was thinking that I would have to use table 1006.3.2(2) which then is my travel distance of 75'-0" to the exit access stair?
or to the front door of the building?

• regarding the occupant load, per 1004.1.1.3 Adjacent stories, I am not required to add
occupant load of 1st floor and 2nd floor so technically I could get by with one exit? is that not correct?

 

[Francis Vineyard]

• in my mind I was thinking that I would have to use table 1006.3.2(2) which then is my travel distance of 75'-0" to the exit access stair?
or to the front door of the building?

• regarding the occupant load, per 1004.1.1.3 Adjacent stories, I am not required to add
occupant load of 1st floor and 2nd floor so technically I could get by with one exit? is that not correct?

EXIT ACCESS. That portion of a means of egress system that leads from any occupied portion of a building or structure to an exit.

Timothy thank you for citing 1004.1.1.3! You are correct; that is a new section and a significant change that allows occupant loads from adjacent stories need not be added together even in those situations where an unenclosed exit access stairway.

That new section will to take me some time to chew on crow.

 

[steveray]

CPET (or travel distance)is measured to a "protected" exit or the discharge....

 

[RLGA]

CPET (or travel distance)is measured to a "protected" exit or the discharge....

Common Path of Egress Travel (CPET) is a part of the travel distance, but is not always the entire travel distance (in most cases it is not). CPET is the distance an occupant must travel before they reach a point where they have the option to take one or more separate and distinct paths to two separate exits. A space that has a single door to a corridor that provides access to two separate exits has a CPET consisting of the travel distance from the most remote point in the room to the exit access door leading to the corridor--thus, CPET is a portion of the travel distance. When a space has a single door directly to the exterior (i.e., exit), then the distance from the most remote point to the door is both the CPET and the travel distance.

Regarding the OP, Table 1006.2.1 is limited to spaces and not stories. For stories, you must either use 1006.3.2(1) or (2); in your case, 1006.3.2(2) is applicable since this is a Group B occupancy. If the occupant load is less than 30 on the second story, then you are permitted to have one exit from the story. The CPET distance is measured from the most remote point on the story to the exit on the ground floor--it cannot be measured to the first riser of the stair, even if the stair was enclosed, since the stair is part of the CPET. The first or ground floor is permitted a single exit if the occupant load is less than 50.

 

[Francis Vineyard]

1004.1.1.3 Adjacent stories. Other than for the egress components designed for convergence in accordance with Section 1005.6, the occupant load from separate stories shall not be added.

In your opinion in accordance with 2015 section 1004.1.1.3 the single exit door can swing inwards serving a cumulative occupant load of 55 (2nd floor 25 + 1st floor 30)?

 

[RLGA]

1004.1.1.3 Adjacent stories. Other than for the egress components designed for convergence in accordance with Section 1005.6, the occupant load from separate stories shall not be added.

In your opinion in accordance with 2015 section 1004.1.1.3 the single exit door can swing inwards serving a cumulative occupant load of 55 (2nd floor 25 + 1st floor 30)?

Yes. Since occupant loads are not cumulative between stories (except for converging occupant loads), the door's requirements are based on the greatest single occupant load to use the door.

 

[steveray]

Common Path of Egress Travel (CPET) is a part of the travel distance, but is not always the entire travel distance (in most cases it is not). CPET is the distance an occupant must travel before they reach a point where they have the option to take one or more separate and distinct paths to two separate exits. A space that has a single door to a corridor that provides access to two separate exits has a CPET consisting of the travel distance from the most remote point in the room to the exit access door leading to the corridor--thus, CPET is a portion of the travel distance. When a space has a single door directly to the exterior (i.e., exit), then the distance from the most remote point to the door is both the CPET and the travel distance.

Regarding the OP, Table 1006.2.1 is limited to spaces and not stories. For stories, you must either use 1006.3.2(1) or (2); in your case, 1006.3.2(2) is applicable since this is a Group B occupancy. If the occupant load is less than 30 on the second story, then you are permitted to have one exit from the story. The CPET distance is measured from the most remote point on the story to the exit on the ground floor--it cannot be measured to the first riser of the stair, even if the stair was enclosed, since the stair is part of the CPET. The first or ground floor is permitted a single exit if the occupant load is less than 50.

Thanks for expanding and clarifying Ron!....I should have said "in a single exit situation, CPET and travel distance...." They do both stop at an exit, but CPET can stop before if you have 2 to choose from...

 

[Francis Vineyard]

Before this I had not thought to consider there would be a difference for door swings between in an area containing 50 or more and for doors serving an occupant load of 50 or more.

 

[Timothy M. Stone]

Thanks everyone, in the end I was hoping sec 1006.3.2(2) did not apply in this scenario, but it appears I i will need to
provide a 2nd exit on first floor, because I have to travel 100'-0" from most remote point on 2nd floor until I reach the
front door on first floor, bummer

 

[JBI]

I think part of the logic for not combining the occupants from different stories is that most or all of the first floor occupants will be out before the second floor occupants get down the stairs. Since they will not necessarily need the door at the same time, so no need to combine them.

 

[Timothy M. Stone]

My only way to solve the proble is to look at the 2nd floor as a mezzanine & add a second door on 1st floor

 

[RLGA]

My only way to solve the proble is to look at the 2nd floor as a mezzanine & add a second door on 1st floor

Does it qualify as a mezzanine? I doubt it, since the area of the second floor is greater than 1/3 of the floor area below and the second floor probably would not meet the openness requirements. See Section 505.

 

[JBI]

I agree with Ron (RLGA). Mezzanine is a specific situation and clearly defined and regulated in the Code.

 

[Paul Sweet]

An exterior stair might be an option. It doesn't have to be protected, unless the code has changed recently.

 

[Phil B]

Does it qualify as a mezzanine? I doubt it, since the area of the second floor is greater than 1/3 of the floor area below and the second floor probably would not meet the openness requirements. See Section 505.

This is an old post, and there is a similar one on the forum.
My question is that if you got the travel distances correct, and had the required occupancy loads (B occupancy), would a single open exit access stair comply with communicating space requirements of NFPA 101 8.6.6 if all the walls were half high?