Exterior exit stair & travel distance

[Sifu]

2018 IBC. Given a 2 story building, VB, Sprinklered, assumed B occupancy. 2nd story has two exit stairs, one is an interior exit access stair, 2nd is a new proposed exterior exit stair.
The building is long and narrow, with each exit at the narrow end. If they were to make two spaces out of the 2nd floor, limiting access of each space to just one of the stairs are we out of t1006.3.3(2) since the story now has 2 exits? If so, then are we now only concerned with common path of egress travel (assume OL does not require two exits, and EATD is fine)? If that is the case, does the CPET get measured to the exit door leading to the stair, or all the way to the level of exit discharge? Note that per 1027.6 it does not require the exterior exit stair protection since 2 stories, so the idea that they are reaching a protected "exit" may not be the case. But if they did protect it anyway, would that make a difference?

FYI, there are 3 proposals. Two are multiple flight, switchback stairs that would exceed CPET based on a measurement from the middle point of the story, the 3rd is a straight run, which would be much closer to the 100' per t1006.2.1.

This is an existing, old building, it originally had a straight run stair, and was one single occupancy. Now they want to divide it. They tore the original straight run stair off without a permit, and with a really bad plan for the future, which went down in flames. They really want the switch backs, but they won't work because of distance to the lot line, (a straight stair will if placed in the center) but I am researching other possible issues in case they go the AMMR route with the city.

 

[Yankee Chronicler]

The building is long and narrow, with each exit at the narrow end. If they were to make two spaces out of the 2nd floor, limiting access of each space to just one of the stairs are we out of t1006.3.3(2) since the story now has 2 exits? If so, then are we now only concerned with common path of egress travel (assume OL does not require two exits, and EATD is fine)? If that is the case, does the CPET get measured to the exit door leading to the stair, or all the way to the level of exit discharge? Note that per 1027.6 it does not require the exterior exit stair protection since 2 stories, so the idea that they are reaching a protected "exit" may not be the case. But if they did protect it anyway, would that make a difference?

With the exterior exit stair, the building will have two exits for the second floor, so IBC Table 1006.3.3 is satisfied. [My 2021 IBC doesn't have a table 1006.3.3(2).]

Does the building meet IBC 1006.3.4 #1 and Table 1006.3.4(2)? If so, each space is okay. If not, In addition to common path of travel, you also have to satisfy requirements for spaces with access to a single exit or singles means of egress -- IBC section 1006.2.1 and Table 1006.2.1. (Which pretty much deals with common path of exit travel.)

 

[mtlogcabin]

You really need to be in the IEBC especially if it is not a change of use, determine which of the 3 methods you want to use and design it from there.
There is no CPET in the IEBC. Fire escapes may be an option for a second exit.
A change of use will more than likely send you to IBC chapter 10 for egress requirements.

 

[Sifu]

This is an inquiry for what the design of the stairs off of a 2nd story need to be. The space configuration and occupancy classification of the 2nd story have not been determined. I am trying to make sure a stair is not given planning approval without the limitations that might come with the configuration and occupancy once it hits my desk, and based on the knowledge that they wish to divide that story into 2 units.

To be more clear, the building will be divided so that the front tenant will have access to the front stair, and the rear unit will have access to the rear stair. The story will have two exits, however the tenants will not have access to 2 exits. I am not sure how the building can meet t1006.3.3 #1 ('21 1006.3.4 #1) if neither space meets it.

It seems that the story is fine...it has 2 exits, and then each space would then need to comply with 1006.3.3 #2 (1006.3.4 #2 in the '21), so we go to table 1006.3.3(2) (1006.3.4(2) in the '21). There is a difference in the '18 and '21 for these tables, but I believe the '18 had an errata to correct it, so I will use the '21 language, which is EATD. So I think each individual space must be within the EATD distances in t1006.3.3(2)/1006.3.4(2) in order to be compliant. If I have that right, where is the distance measured to? I have believed it is measured to the bottom of the stairs, in line with the requirement for exit access stairs. It has been opined though, that if the exterior wall of the exterior exit stair is rated then the distance could stop at the exit access door. If it is to the bottom, then only a straight run stair, sticking out into the parking lot is close.

Before everyone piles on for attempting this without a design, note that this has been an on-going issue, and the city has a bit of egg on it's face. Apparently, the owner spoke with the planning department during a previous site development project for the rear parking lot and the planner told them they could build a set of steps that broke just about every rule. Then when they submitted to me (after tearing the existing stair off), I pointed out all those rules. Planners love the pretty pictures.... So I am trying to find the best solutions to the city's problem, as much as finding a solution for the owner's problem.

 

[Sifu]

You really need to be in the IEBC especially if it is not a change of use, determine which of the 3 methods you want to use and design it from there.
There is no CPET in the IEBC. Fire escapes may be an option for a second exit.
A change of use will more than likely send you to IBC chapter 10 for egress requirements.

It is likely a change of use, the building was gutted and permitted as a core shell without occupancy and with the stipulation that no occupancy could be granted of the 2nd floor until the stair issue is resolved which is what they are attempting now. (See my other post as to why this happened.) Now they want to occupy the 2nd floor with some as yet determined occupancy. But even if was the same, now that they have no stairs at all, there must be some standard by which the new stairs are built, so I go to the IBC. The stairs will be the only way in or out, so even if the city planners allowed the fire escape (they wouldn't), it won't fly.

FWIW, when this issue arose, I suggested they could have left the existing stair based on the IEBC, but since they tore it down (without a permit) now they were stuck. They said they couldn't have left it as it was dangerous...I pulled up some old photos and agreed.

 

[mtlogcabin]

If the stairs are exterior, then IMHO that is where the exit access travel distance ends.
Good luck

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

[BE] 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.

 

[Yankee Chronicler]

It seems that the story is fine...it has 2 exits, and then each space would then need to comply with 1006.3.3 #2 (1006.3.4 #2 in the '21), so we go to table 1006.3.3(2) (1006.3.4(2) in the '21). There is a difference in the '18 and '21 for these tables, but I believe the '18 had an errata to correct it, so I will use the '21 language, which is EATD. So I think each individual space must be within the EATD distances in t1006.3.3(2)/1006.3.4(2) in order to be compliant. If I have that right, where is the distance measured to? I have believed it is measured to the bottom of the stairs, in line with the requirement for exit access stairs. It has been opined though, that if the exterior wall of the exterior exit stair is rated then the distance could stop at the exit access door. If it is to the bottom, then only a straight run stair, sticking out into the parking lot is close.

The IBC has an entire section on Exterior Exit Stairways and Ramps (section 1027 in the 2021 IBC). These are, indeed, exit stairs. The path of exit access travel ends at the doorway out of the upper story onto the stair landing. It's not a question of " if the exterior wall of the exterior exit stair is rated then the distance could stop at the exit access door." In order for an exterior stair to qualify as an exterior EXIT stair the exterior wall must be rated for a distance of ten feet in all directions from the stair. If it satisfies this, it's an "exit" and the access travel ends when you go through the door.

If the exterior wall isn't rated for ten feet in all directions from the stair, then it's not an exit stair, it's part of the exit access.

xx

 

[Sifu]

If the exterior wall isn't rated for ten feet in all directions from the stair, then it's not an exit stair, it's part of the exit access.

xx

Which would make it an exterior exit access stair (something there is no definition for, but is being floated in my code development group), meaning the measurement would not stop until at the level of discharge per 1017.3.1 (2018). However, it can still be an exterior exit stair and NOT have the wall ratings per 1027.6 exc. #1 (2018), so my certainty wanes a bit. I am trying to determine if as an exterior exit stair, the measurement stops at the door even if the rating is not provided by the exception.

 

[Yankee Chronicler]

Which would make it an exterior exit access stair (something there is no definition for, but is being floated in my code development group), meaning the measurement would not stop until at the level of discharge per 1017.3.1 (2018). However, it can still be an exterior exit stair and NOT have the wall ratings per 1027.6 exc. #1 (2018), so my certainty wanes a bit. I am trying to determine if as an exterior exit stair, the measurement stops at the door even if the rating is not provided by the exception.

Well, I agree that it's confusing. Section 1027 addresses Exterior Exit Stairways and Ramps. 1027.6 addresses protection of Exterior Stairways and Ramps. The exception you're looking at does remove the fire separation requirement for exterior exit stairs serving buildings of two stories or less above grade in other than R-1 and R-2 occupancies. What the exception does NOT do is the re-define the stair as an exit access stair.

In fact, if you read exceptions #2 and #3, in discussing other exceptions for the rated separation those exceptions explicitly continue to refer to the stair as an exterior exit stair. It's tempting to say that it's now an exit access stair and therefore to measure exit access travel distance all the way to the bottom of the stair, but I don't think the code actually supports that.

It's the same section number and the same exceptions in IBC 2021. The 2021 Commentary offers this:

Exception 1 indicates that the exterior wall is not
required to be rated for occupancies (other than
Groups R-1 and R-2) that are two stories or less above
grade where the level of exit discharge is at the lower
story. The reason for this exception is that in cases of
fire in low buildings, the occupants are usually able to
evacuate the premises before the fire can emerge
through exterior wall openings and endanger the exterior
exit ramp or stairways. In hotels and apartments,
however, the occupants’ response to a fire emergency
could be significantly reduced because they may be
either unfamiliar with the surroundings or sleeping.

Based on the language of the code and the information in the Commentray, I think the door at the upper landing is still the exit door, and that exit access travel distance ends at that door. (And I agree that this seems counter-intuitive.)

 

[mtlogcabin]

If the exterior wall isn't rated for ten feet in all directions from the stair, then it's not an exit stair, it's part of the exit access.

No, it is a non-code compliant exit stair.
Call it what it is and not something it isn't.

 

[steveray]

If the exterior wall isn't rated for ten feet in all directions from the stair, then it's not an exit stair, it's part of the exit access.

xx

Watch the exceptions:

Exceptions:

1. Separation from the interior of the building is not required for occupancies, other than those in Group R-1 or R-2, in buildings that are not more than two stories above grade plane where a level of exit discharge serving such occupancies is the first story above grade plane.

 

[Sifu]

I advised my boss of my opinion as follows:
That it is an exterior exit stair but without the required wall ratings (by exception) the exit access travel distance must be measured to the level of discharge. The way I see it they have a few options: 1) Rate the exterior wall and openings to stop the measurement at the door to the stairs, 2) Create an interior path of travel that provides access to both exits, 3) keep the EATD distance as measured to the level of exit discharge and provide a space plan that limits that distance to that required by t1006.3.3(2), 4) Abandon the multi-tenant idea so that the single tenant has access to both exits.
If their architect has another idea I am all ears.

 

[Yankee Chronicler]

FWIW, when this issue arose, I suggested they could have left the existing stair based on the IEBC, but since they tore it down (without a permit) now they were stuck. They said they couldn't have left it as it was dangerous...I pulled up some old photos and agreed.

The IEBC has a provision allowing existing fire escapes to be replaced by new fire escapes. It's applicable if space considerations don't allow the construction of a conforming exterior stair. I don't remember the section, but we just went through this with an existing building so I know it's in there.

 

[Yankee Chronicler]

No, it is a non-code compliant exit stair.
Call it what it is and not something it isn't.

If it complies with an exception specifically listed in the code, how is it non-code compliant?

 

[mtlogcabin]

Complying with a specifically listed code exception for exterior exit stairways in 1027 does not change the name of what you are reviewing nor the code section you are reviewing it under unless it sends you to a specific code section. 1019 deals with stairways within a building, 1027 deals with stairways located outside of the building envelope. When we start to interchange the wording, the code uses, it creates confusion, especially within the design community. Example: People misuse the term firewall quite frequently instead of the correct identifying terms, Fire Partition, Fire Barrier and Fire Wall.

SECTION 1019, EXIT ACCESS STAIRWAYS AND RAMPS

SECTION 1027, EXTERIOR EXIT STAIRWAYS AND RAMPS

 

[Yankee Chronicler]

Complying with a specifically listed code exception for exterior exit stairways in 1027 does not change the name of what you are reviewing nor the code section you are reviewing it under unless it sends you to a specific code section. 1019 deals with stairways within a building, 1027 deals with stairways located outside of the building envelope. When we start to interchange the wording, the code uses, it creates confusion, especially within the design community. Example: People misuse the term firewall quite frequently instead of the correct identifying terms, Fire Partition, Fire Barrier and Fire Wall.

SECTION 1019, EXIT ACCESS STAIRWAYS AND RAMPS

SECTION 1027, EXTERIOR EXIT STAIRWAYS AND RAMPS

But you posted that it's a "non-code compliant" exterior exit stair.

I agree that it's an exterior exit stair. It is allowed to be unprotected because of Exception number 1. Therefore, it is code compliant. So why would you insist that it's an exterior exit stair but then say it's not con compliant? Exception number 1 is part of the code.

If it complies with exception number 1, it's code compliant.

 

[mtlogcabin]

Because of Sufi's comment

Which would make it an exterior exit access stair (something there is no definition for, but is being floated in my code development group), meaning the measurement would not stop until at the level of discharge per 1017.3.1 (2018)

By calling it an exterior access stair and limiting the travel distance based on the access travel distance requirements he would be misapplying one code section requirement to another that clearly does not have a travel limit requirement.

Look at section 1028 exit discharge, there is no travel distance limitations and any reference to stairs are "interior".

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

[BE] EXIT DISCHARGE, LEVEL OF. The story at the point at which an exit terminates and an exit discharge begins.

 

[Sifu]

I can't strongly argue this issue, but my thinking is that EATD is measured within the exit access, and terminates at an exit, and I believe the intent is that it stops because you enter a protected element or at a door at the level of exit discharge. Without the exception an exterior exit stair is protected, with the exception it is not, therefore the protection afforded is lost. This is not completely supported by code because it is still an exit, and may be incorrect, but it is the logic I am using.

This is not me making a comment noting a deficiency on a plan, it is an opinion, provided to the CBO, made in reaction to questions with 3 different stair option sketches, regarding a situation that has spiraled out of control. I am going to render a conservative opinion but I welcome the architect's own interpretation, and if they are smart enough to make the same argument you do I would consider it. And if they do, it means they have been reading this thread, otherwise it is doubtful.

FWIW this is not an existential issue, it can be overcome, either with proper space planning or proper design. There are other existential issues that need to be overcome by the designer, so this issue is probably secondary. They are at 9 months of trying to bulldoze their way into this, so my opinion may be skewed to the hard side. Each of the three sketches has previously been submitted, on multiple occasions, and rejected for multiple reasons, I guess they are just hoping we will forget because it has been a few months since the last try.

 

[steveray]

Not sure if this helps?

1027.1 General.​

Exterior exit stairways and ramps serving as an exit component in a means of egress system shall comply with the requirements of this section.

❖ Stairways and ramps can be exit access, exit or exit discharge elements. Exterior exit access and exit discharge stairways and ramps typically involve a change of elevation of less than a story. Exterior exit access stairways or ramps between stories must comply with Section 1019.3 and, where permitted as part of the required means of egress, are limited by Section 1006.3. Exit stairways and ramps traverse a full story or more. Interior exit stairways and ramps must be enclosed in accordance with Section 1023. This section addresses exterior stairways and ramps that function as exit elements.
Exterior exit stairways and ramps are an important element of the means of egress system and must be designed and constructed so that they will serve as a safe path of travel. The general requirements in Section 1011 also apply to exterior stairways (for ramp provisions, see Section 1012).
Outdoor stadiums and open parking garages are examples of buildings that may appear to have exterior exit stairways, but actually have open exit access stairways (Sections 1017, 1019 and 1030).

 

[Yankee Chronicler]

I can't strongly argue this issue, but my thinking is that EATD is measured within the exit access, and terminates at an exit, and I believe the intent is that it stops because you enter a protected element or at a door at the level of exit discharge. Without the exception an exterior exit stair is protected, with the exception it is not, therefore the protection afforded is lost. This is not completely supported by code because it is still an exit, and may be incorrect, but it is the logic I am using.

Correct. The pedant in me wants to say that EATD begins at the most remote point and is measured along the path of exit access travel, but I agree that the EATD ends either at the entrance to an exit or at an exit door at the level of exit discharge.

Since IBC section 1027 is dedicated to exterior exit stairs, and the exceptions explicitly provide for conditions under which those stairs can be unrated/unprotected, I think the code fully supports this concept. As I commented above, it seems counter-intuitive, but it says what it says. The exceptions create limited situations in which a stair can be an exit stair (not exit access) yet not be protected.

 

[Sifu]

Not sure if this helps?

1027.1 General.​

Exterior exit stairways and ramps serving as an exit component in a means of egress system shall comply with the requirements of this section.

❖ Stairways and ramps can be exit access, exit or exit discharge elements. Exterior exit access and exit discharge stairways and ramps typically involve a change of elevation of less than a story. Exterior exit access stairways or ramps between stories must comply with Section 1019.3 and, where permitted as part of the required means of egress, are limited by Section 1006.3. Exit stairways and ramps traverse a full story or more. Interior exit stairways and ramps must be enclosed in accordance with Section 1023. This section addresses exterior stairways and ramps that function as exit elements.
Exterior exit stairways and ramps are an important element of the means of egress system and must be designed and constructed so that they will serve as a safe path of travel. The general requirements in Section 1011 also apply to exterior stairways (for ramp provisions, see Section 1012).
Outdoor stadiums and open parking garages are examples of buildings that may appear to have exterior exit stairways, but actually have open exit access stairways (Sections 1017, 1019 and 1030).

It has been stated that exit access stairs apply to interior stairs. Most code points to that, and common use is interior. However, it is not specifically stated that an exit access stair and the provisions for them can't be employed on the exterior. But, as is often the case, there is contradictory language. This particular commentary (and others that do the same thing) drive me nuts. As far as I know, there is no other mention or reference for exterior exit access stairways, yet the commentary says they can exist as long as they meet 1019.3, but that section is awfully hard to apply to an exterior stair. Then add to that the "typically" term, implying there is an "atypical" exit access stair, that is known as an exterior exit access stair. So in this case, with a 2-stroy building, the exterior stair could exist as an exterior exit access stair, based on 1019.3 #1. At least according to the commentary.