Can we indulge me one more time on the # of exits per story?

[Code Neophyte]

I had a similar situation on the "old board" a couple of years ago, and now here I am again. Just want to make sure my interpretation is correct:

The subject building is a three story (two above grade plane), III-B, B occupancy, ~9,000 s.f./floor. There is a fourth story - or what the architect is calling a "mezzanine" (although it is not open in accordance with 505.4, so I would consider it a fourth story). There is only one stair serving the fourthfloormezzanine, and the elevator (in the same vertical enclosure). It appears to me that the O.L. for the "area" (one large, open room) is around 20. Does this level/mezzanine need two exits?

 

[cda]

Re: Can we indulge me one more time on the # of exits per story?

does it meet 505 to include 505.3??

is this thing entirely above the third floor as in another story???

 

[Big Mac]

Re: Can we indulge me one more time on the # of exits per story?

You have stated that the occupant load of the floor level is enclosed with an occupant load greater than 10 and has only one exit. Therefor it is not in compliance with the provision set forth to qualify as a mezanine. Therefore, it must be considered a story.

The next consideration is common path of travel. Can the occupants of the floor level reach a point where they have access to two separate and distinct paths of travel within 75' (100' if sprinkled).

If yes, the next thing to consider is exit travel distance.

 

[mtlogcabin]

Re: Can we indulge me one more time on the # of exits per story?

505.3 Egress.

Each occupant of a mezzanine shall have access to at least two independent means of egress where the common path of egress travel exceeds the limitations of Section 1014.3.

1014.3 Common path of egress travel.

Exceptions:

1. The length of a common path of egress travel in Group B, F and S occupancies shall not be more than 100 feet (30 480 mm), provided that the building is equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1.

2. Where a tenant space in Group B, S and U occupancies has an occupant load of not more than 30, the length of a common path of egress travel shall not be more than 100 feet (30 480 mm).

The OP stated an OL of 20 for this space. If it is the same tenant as the space it exits into would you give them the 100 ft CPET :?:

 

[Code Neophyte]

Re: Can we indulge me one more time on the # of exits per story?

I hastily threw together the OP before I threw myself out the office door at closing time, so I may not have described the design as well as I could have. The building is a large rectangle with a hip roof (7 or 8/12), so that this "mezzanine" area is similar to an attic in resi. construction. So above the 9,000 square foot ceiling of the second floor (above grade plane), as the rafters climb at a 7 or 8 and you throw in knee walls at habitable ceiling height for the "attic", you only have an area of around 2,000 square feet. The only exit is into a vertical exit enclosure, but it re-enters the building at the level of exit discharge, so the "Common Path" would be measured from the most remote point of the "attic" through the door of the stairs, down the stairs to the second floor, whereupon the occupant could enter the second floor and travel to the other stair enclosure (which does exit to the exterior), or remain in the first stair enclosure and follow it to the main level. If I'm correct about that, the CPET is over 100'.

In addition to all of this, I guess I'm asking for clarification of §1019.1 (2006 IBC) - if the area cannot be considered a mezzanine, and therefore a story, must it have a minimum of two exits? It seems like the last time I asked, the majority of opinions were that the exceptions in 1019.1 did not apply to stories - only to spaces within stories.

 

[peach]

Re: Can we indulge me one more time on the # of exits per story?

it sounds like a story...

 

[texasbo]

Re: Can we indulge me one more time on the # of exits per story?

You have stated the occupant load of the space in question is around 20, so I'm assuming it's B occupancy/office like the rest of the building? If so, then I agree with you and others that it is a story, and per Table 1019.1 is required to have 2 exits. Table 1019.2 could not even be considered, since it can only be used when you have a maximum of 2 stories above grade plane.

If however, this space is, say storage, it could possibly be a mezzanine whether it's open or not (provided it's not more than 1/3 of the story below), and then we WOULD have to start looking at other things like CPET.

 

[kilitact]

Re: Can we indulge me one more time on the # of exits per story?

Code Neophyte wrote in part:

The only exit is into a vertical exit enclosure, but it re-enters the building at the level of exit discharge, so the "Common Path" would be measured from the most remote point of the "attic" through the door of the stairs, down the stairs to the second floor, whereupon the occupant could enter the second floor and travel to the other stair enclosure (which does exit to the exterior), or remain in the first stair enclosure and follow it to the main level.

travel distance measurements stop once you enter the vertical exit enclosure

 

[Code Neophyte]

Re: Can we indulge me one more time on the # of exits per story?

Texasbo: I agree that T1019.2 cannot be used (besides, the building has two exits on the upper and lower floors, and four on the main floor, so it's not a 'Building with a single exit' situation - but how about §1015.1? §1019.1 lists 1015.1 as an exception to the requirements of T1019.1, if OL<49, CPET < 75' (building is not sprinklered), or the incidental uses listed in 1015.3, 1015.4, and 1015.5.

In my earlier post, I said that the stair shaft re-entered the building on the main level; after reviewing this, I see that it opens into a protected vestibule, which discharges to the exterior, so to revise what I said earlier, CPET would be from the most remote point of the "mezzanine" to the door of the stair enclosure is around 63 feet.

So, again, could this be considered a 'space' in accordance with 1015.1? Or does a story above the second floor require two exits - period?

 

[kilitact]

Re: Can we indulge me one more time on the # of exits per story?

Code Neophyte wrote;

In my earlier post, I said that the stair shaft re-entered the building on the main level; after reviewing this, I see that it opens into a protected vestibule, which discharges to the exterior, so to revise what I said earlier, CPET would be from the most remote point of the "mezzanine" to the door of the stair enclosure is around 63 feet.

One exit required from this floor

 

[Plans Approver]

Re: Can we indulge me one more time on the # of exits per story?

I think its commonly considered that 1019.1 requires two exits from each story, it really doesn't say that directly.

1019.1 requires 2 exits (minimum) from all spaces and rooms within each story. Once you have established it is not a building with one exit (1019.2) and it is not a mezzanine (505.3, 505.4 w/ exceptions), then all of the spaces and rooms on the fourth floor require two exits. And, by default the story. 1015.1 specifically allows certain spaces to have one exit doorway, but, once leaving the space, two exits are required. The exit enclosures from the fourth floor to the third floor are then subject to 1020.1 and its exceptions, possibly 8 or 9. The fourth floor wouldn't be a windowless story (903.2.10), would it?

This situation has been the subject of several published ICC interpretations over the years and is addressed in a backhanded way in the interp currently on their web site: http://www2.iccsafe.org/cs/committeeAre ... _47_08.pdf.

Below is an interp I received when asking a similar question for a basement with one exit. (2000 IBC, I don't think anything has changed, except the section numbers.)

It is my understanding that your e-mail poses the following questions:

Q1: Does the Basement qualify as a space with one exit, as IBC 1004.2.1

is mentioned as a modifier to IBC 1005.2.1 (basement occupant load is

less than 50 and common path of travel is less than 100 feet)?

A1: No. The basement would qualify as a space with one exit, but each

floor must have two exits per Section 1005.2.1. A space within the

basement would be permitted to have one exit access

doorway for access to the two exits of the floor.

Q2: If the answer to question #1 is no, and the owner were to elect

to not use the basement for any use or purpose except to maintain

existing electrical panels and hot water tanks, would two (2) exits

still be required?

A2: Yes.

Q3: If the owner were to elect to not use the basement for any

use or purpose except to maintain existing electrical panels and

hot water tanks, would the partial sprinkler system

(IBC 903.2.12. 1) still be required (the stair would be

maintained as access to the space)?

A3:Yes.

We are pleased to provide you with the opinions stated herein.

It should be noted, however, that the final interpretation is

the responsibility of the local building official.

For what it's worth.

 

[High Desert]

Re: Can we indulge me one more time on the # of exits per story?

I agree with Plans Approver but I think 1019 does cleary indicate that 2 exits are required. Table 1019.1 requires 2 exits per story with an occupant load of 1-500. If you meet the criteria of Table 1019.2, then you can go down to 1 exit. Since it is more than 2 stories, the maximum allowed in Table 1019.2, you have to provide 2 exits from the 4th story, regardless of CPET or the existence of an exit enclosure.

 

[Code Neophyte]

Re: Can we indulge me one more time on the # of exits per story?

Great responses - special thanks to Plans Approver for the suggestion about windowless stories! I hadn't gotten there yet. I would like to think I would have caught it, but then again...

 

[texasbo]

Re: Can we indulge me one more time on the # of exits per story?

I agree with Plans Approver but I think 1019 does cleary indicate that 2 exits are required. Table 1019.1 requires 2 exits per story with an occupant load of 1-500. If you meet the criteria of Table 1019.2, then you can go down to 1 exit. Since it is more than 2 stories, the maximum allowed in Table 1019.2, you have to provide 2 exits from the 4th story, regardless of CPET or the existence of an exit enclosure.

I completely agree with this post; in fact it pretty much echoes my earlier post.

Code Neophyte: You didn't answer my question about the use of the space under consideration. Has the applicant told you what the space is used for?

 

[kilitact]

Re: Can we indulge me one more time on the # of exits per story?

Section 1021 #5; within a story, rooms and spaces complying with Section 1015.1 with exits that discharge directly to the exterior at the level of exit discharge, are permitted to have one exit

I think the code would allow one exit.

 

[Plans Approver]

Re: Can we indulge me one more time on the # of exits per story?

Section 1021 #5; within a story, rooms and spaces complying with Section 1015.1 with exits that discharge directly to the exterior at the level of exit discharge, are permitted to have one exit I think the code would allow one exit.

Yep, under 2009 IBC. (Just another code change for less safety.)

I thought we were talking 2006 IBC by the code sections posted by Code Neo.

 

[kilitact]

Re: Can we indulge me one more time on the # of exits per story?

Why would a code official (s) not use the incoming code to approve plans?? less safety, no, I think this is more realistic. Two exits for one occupant :roll:

 

[mtlogcabin]

Re: Can we indulge me one more time on the # of exits per story?

Why would a code official (s) not use the incoming code to approve plans??

Because it is not adopted and may never be adopted. Do you use the latest edition of a standard or the one referenced in the adopted code. I like to stay with what has been adopted.

 

[kilitact]

Re: Can we indulge me one more time on the # of exits per story?

In Oregon, it will be adopted in a matter of weeks. If I see code that is approved or is going to be approved, yes I will use it, as an alternate method if nothing else. If your looking for ways to disapprove a project, instead of using all the tools at your disposal to approve it, your not providing good service! Try to think outside of the box your in.

 

[High Desert]

Re: Can we indulge me one more time on the # of exits per story?

Before anyone jumps to conclusions on this, Section 1021.1 #5 says "exits that discharge directly to the exterior at the level of exit discharge, are permitted to have one exit." An exit from the 4th story would not discharge directly to the exterior at the level of exit discharge. Going down the stairs you would still be in the exit and not at the level of exit discharge until you reached the exit discharge at the bottom of the stairs.

EXIT DISCHARGE, LEVEL OF. The story at the point at

which an exit terminates and an exit discharge begins.

This code change was intended for spaces or rooms that had exiting independant from the required building egress system. The required egress from the 4th floor in the 2009 is still a minimum of 2 exits. Now if the building was built into a hillside but was still considered a 4-story building, and one of the spaces had an exit at the higher grade, I think you could permit it. But to say this section trumps the number of required exits from a story is not the proper application of the code.

I remember the discussion and testimony at the Palm Springs hearing on this item and that is my recollection. Now if I have misinterpreted what the level of exit discharge is, let me know.

 

[Big Mac]

Re: Can we indulge me one more time on the # of exits per story?

I think High Dessert nailed it.

 

[Code Neophyte]

Re: Can we indulge me one more time on the # of exits per story?

Texasbo: Sorry I neglected to answer you. The answer is, no - the architect has not provided the use of the space. It's another reason my antennae went up. The plans are very detailed, except for this area. Basically, they just drew the rectangle, labeled it "mezzanine", and showed a typical U419 wall around the perimeter. So my first thought was, "Hey! That's not a mezzanine......is it??" Then the internal debate on that, then, "OK, if it's not, then it's a story, which requires two exits". If I were to anticipate how they would classify it, it would probably be 'B' - the remainder of the building is a single-occupancy classification of 'B'.

We have adopted the '06 codes, and will not adopt the '09, and will probably only be dragged into the '12 kicking and screaming.

 

[brudgers]

Re: Can we indulge me one more time on the # of exits per story?

Before anyone jumps to conclusions on this, Section 1021.1 #5 says "exits that discharge directly to the exterior at the level of exit discharge, are permitted to have one exit." An exit from the 4th story would not discharge directly to the exterior at the level of exit discharge. Going down the stairs you would still be in the exit and not at the level of exit discharge until you reached the exit discharge at the bottom of the stairs.EXIT DISCHARGE, LEVEL OF. The story at the point at

which an exit terminates and an exit discharge begins.

This code change was intended for spaces or rooms that had exiting independant from the required building egress system. The required egress from the 4th floor in the 2009 is still a minimum of 2 exits. Now if the building was built into a hillside but was still considered a 4-story building, and one of the spaces had an exit at the higher grade, I think you could permit it. But to say this section trumps the number of required exits from a story is not the proper application of the code.

I remember the discussion and testimony at the Palm Springs hearing on this item and that is my recollection. Now if I have misinterpreted what the level of exit discharge is, let me know.

The exit includes the enclosure and the doors at ground level. See the definition of "exit."

An exit that discharges directly to the exterior is distinct from one that discharges elsewhere, as in the case of an exit that discharges into a lobby on the level of exit discharge, for example. See "1024.1 exceptions."

An exit is an exit, regardless of if it is a door to the exterior or an enclosure.

 

[mtlogcabin]

Re: Can we indulge me one more time on the # of exits per story?

An exit is an exit, regardless of if it is a door to the exterior or an enclosure

Agree but an Exit Discharge is where you leave that exit to reach the public way that would be the door to the exterior

EXIT DISCHARGE. That portion of a means of egress system between the termination of an exit and a public way.