Vertical Exit Enclosures

[rooster]

...and the million dollar question is what part of the any of the codes is allowing you to have one exit from the second floor if you have a travel distance greater than 50?

And the common path of egress section shouldn't come into play unless you have more than one exit.

 

[mtlogcabin]

Short and simple, the new 2012 Code allows 125' of exit access travel distance in a sprinklered building making the need for an exit enclosure and this whole issue of what spaces can open into it a moot issue. What we are providing is a actually higher level of protection.

That is a big change. I just read it and agree your project would fly under the 2012 edition since the exit enclosure is not required.

 

[steveray]

If it flies under a newer code,....ask the AHJ if they will modify to the newer code that they will probably be on soon anyway......that works alot here....

That is a big change. I just read it and agree your project would fly under the 2012 edition since the exit enclosure is not required.

 

[brudgers]

Yeah, just pick a section of IBC 2012 here.

Part of covered mall buildings from 2006.

Maybe a provision from NFPA 101, too.

But only so long as you include Hammurabi.

 

[rooster]

That is a big change. I just read it and agree your project would fly under the 2012 edition since the exit enclosure is not required.

How does it fly if he only has one exit? Am I missing something?

 

[mtlogcabin]

The 2012 allows a single exit from a 2nd floor serving no more than 4 dwelling units with a maximum access travel distance of 125 ft in a sprinklered building (doubled from the 2009 code) CPOT is not applicable in this case

Travel distance is from the most remote point in the dwelling (building) to the exit

A typical apartment can eat up 50 to 70 feet of travel distance pretty easily. My guess is the extra distance was an easy way to eliminate the exit enclosure on smaller apartment buildings.

My question of confusion is the code says 4 units per story not per stair served. The OP has 6 units on the second floor with 2 stairs serving 3 units each. Is it code compliant by a literal interpretation? If not would it be code compliant under the "intent" of the code. No more than 4 dwelling units can use the same exit stair

 

[rooster]

The 2012 allows a single exit from a 2nd floor serving no more than 4 dwelling units with a maximum access travel distance of 125 ft in a sprinklered building (doubled from the 2009 code) CPOT is not applicable in this caseTravel distance is from the most remote point in the dwelling (building) to the exit

A typical apartment can eat up 50 to 70 feet of travel distance pretty easily. My guess is the extra distance was an easy way to eliminate the exit enclosure on smaller apartment buildings.

My question of confusion is the code says 4 units per story not per stair served. The OP has 6 units on the second floor with 2 stairs serving 3 units each. Is it code compliant by a literal interpretation? If not would it be code compliant under the "intent" of the code. No more than 4 dwelling units can use the same exit stair

Thanks for the clarification. The OP was frequently referring to section 1014, so I was under the impression this was the 2012 change.

 

[brudgers]

The 2012 allows a single exit from a 2nd floor serving no more than 4 dwelling units with a maximum access travel distance of 125 ft in a sprinklered building (doubled from the 2009 code) CPOT is not applicable in this case Travel distance is from the most remote point in the dwelling (building) to the exit A typical apartment can eat up 50 to 70 feet of travel distance pretty easily. My guess is the extra distance was an easy way to eliminate the exit enclosure on smaller apartment buildings. My question of confusion is the code says 4 units per story not per stair served. The OP has 6 units on the second floor with 2 stairs serving 3 units each. Is it code compliant by a literal interpretation? If not would it be code compliant under the "intent" of the code. No more than 4 dwelling units can use the same exit stair

IMO, the intent of the code is to limit the number of units per story to reduce the odds of: 1. A fire starting.

2. Someone being asleep during a fire.

Unless there is a firewall creating two buildings, six units doesn't fly.

Of course, neither does the mix and match code analysis.

 

[kilitact]

IMO, the intent of the code is to limit the number of units per story to reduce the odds of: 1. A fire starting.

2. Someone being asleep during a fire.

Unless there is a firewall creating two buildings, six units doesn't fly.

Of course, neither does the mix and match code analysis.

Of course theoretically if the apartments are located in certain parts of town using Milton’s rule you could say that it’s similar to a shopping mall. People shop for all kinds of goodies in the projects

 

[Builder Bob]

The 2012 allows a single exit from a 2nd floor serving no more than 4 dwelling units with a maximum access travel distance of 125 ft in a sprinklered building (doubled from the 2009 code) CPOT is not applicable in this case Travel distance is from the most remote point in the dwelling (building) to the exit A typical apartment can eat up 50 to 70 feet of travel distance pretty easily. My guess is the extra distance was an easy way to eliminate the exit enclosure on smaller apartment buildings.

now the other issue at hand...... so i can have 6,000 SF dwelling units dumping onto a single stairway. Where does the measurement of travel distance start and where does it end if you do not have an exit but only an discharge into the public way in an unrated stairway?

Sounds like more spackling added to make it pretty but doesn't solve the root of the problem.

 

[mtlogcabin]

Where does the measurement of travel distance start and where does it end if you do not have an exit but only an discharge into the public way in an unrated stairway?

It starts in the most remote point within that 6,000 sq ft dwelling and continues down the exit access stairs to the exit.

The 2012 has added and changed the definitions we are all have been using.

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, interior exit ramps, exit passageways, exterior exit stairways and exterior exit ramps and horizontal exits

 

[damstein]

My question of confusion is the code says 4 units per story not per stair served. The OP has 6 units on the second floor with 2 stairs serving 3 units each. Is it code compliant by a literal interpretation? If not would it be code compliant under the "intent" of the code. No more than 4 dwelling units can use the same exit stair

Think of the building as two buildings with 3 units per floor with a 2 hour fire barrier wall in between. (As per mitted by local code) Each half of the building is served by a single exit.

 

[mtlogcabin]

Think of the building as two buildings with 3 units per floor with a 2 hour fire barrier wall in between. (As per mitted by local code)

I see you noted a local code ammendment. I believe the ICC would require a firewall not a fire barrier before it would be 2 separate buildings

 

[brudgers]

Think of the building as two buildings with 3 units per floor with a 2 hour fire barrier wall in between. (As per mitted by local code) Each half of the building is served by a single exit.

Well, now you've got two stairs, so why put in a firewall?

 

[Big Mac]

And the common path of egress section shouldn't come into play unless you have more than one exit.

Wrong - the common path of egress travel is always in play if there is only one exit.

 

[rooster]

And the common path of egress section shouldn't come into play unless you have more than one exit.Wrong - the common path of egress travel is always in play if there is only one exit.

Definitions 1002 IBC 2009

COMMON PATH OF EGRESS TRAVEL

"That portion of exit access which the occupants are required to traverse before two separate and distinct paths of egress travel to two exits are available. Paths that merge are common paths of travel. Common paths of egress travel shall be included within the permitted travel distance."

At one point the OP said the below paragraph where he was asking if he could sub in common path of egress travel for single exit stories:

The other option as I believe was inferred to earlier, would have been to eliminate the need for a "vertical enclosure" all together (read dog vs cat post). However, based on the 2006 code, there appears to be a conrtadiction in that the Code limits travel distance to 50' in R-2 for "Buildings with One Exit" serving 4 units or less, while Section 1014 limits overall "commom path of travel" to 125' if the building is sprinklered per NFPA 13 for R-2 buildings? Could one assume that the 125' limitation would apply? Or would the more stringent of the two be applicable?

 

[Big Mac]

"Definitions 1002 IBC 2009

COMMON PATH OF EGRESS TRAVEL

"That portion of exit access which the occupants are required to traverse before two separate and distinct paths of egress travel to two exits are available."

It is still a commmon path of travel, it is just in htis instance the common path of travel can be 125 feet in a sprinklered building.

This is very similar to the situation where the common path of travel can go from 75' in a Group B occupancy to 100' if the building is sprinkled. Still a common path of travel, it can just be longer if sprinklers are installed.

 

[rooster]

I must be missing something.

If someone came to you with a single exit 2nd story apartment with a travel distance over the allowed travel distance for a single exit second story apartment...you'd be ok wih them citing "common path of egress travel"?

I understand that this is not how the OP resolved this. Instead he went to 2012 IBC where "Stories with One Exit" was revised.

I just don't understand how I'm wrong about the Common Path of Egress Travel. The very definition of CPOET is that it's the single path before two paths are available.

 

[Big Mac]

Let me try this one more time. Section 1014.3 is the Section that deals with common path of travel. Charging language found there states that in all occupancies other than Groups H-1 / H-2 / & H-3, the common path of egress travel may not exceed 75'. Right?

As with many other code sections, there are exceptions granted. In this particular case, there are four exceptions granted. Remember, just because there are exceptions, they are still under the heading of common path of travel. They are exceptions to the basic requirements of the common path of travel.

In this case one of the exceptions, exception #4 specifically, allows the common path of travel in Group R-2 occupancies to be increased to 125' given certain circumstances. It is still a common path of travel, it may just be lengthened if the building is a sprinkled building. Instead of the common path of travel being 75' as required by the original language, it may now be 125' when the building is sprinkled.

It is still dealing with the common path of travel. The code permits this. Yes I would allow it if the building was a sprinkled building.

 

[rooster]

Thanks for taking the time to explain.

So when do you use 1021.2 "Stories with One Exit"?

 

[damstein]

Thanks for taking the time to explain.So when do you use 1021.2 "Stories with One Exit"?

That was the question I had when I mentioned the two different travel distances in my earlier post???

 

[rooster]

I typically use it when I'm considering having a story with one exit.

 

[Big Mac]

In my experience, Table 1021.2 does not come into play very often as it is very limiting. For example it would take a very small building in most cases to qualify. However, the building would not necessarily need to be sprinkled to use this section.

If you will notice, for example the requirement for R-2 occupancies states that the distance referenced is a per floor travel distance. Indicating that the travel distance is to an exit. The exit could be a fire-rated vertical exit enclosure, or it could be the stairway exit at grade. Also note that this exception can only be used for a three-story condition if the is sprinkled. There is no such specified requirement in this part of the code that a two-story condition be sprinkled.

That is somewhat of a moot point because when there are more than three dwelling units, sprinklers are required unless separated with fire-walls.

You may have noticed that there are often conflicting elements in the code that sometimes makes use of some sections almost non-existent.

 

[mtlogcabin]

That is somewhat of a moot point because when there are more than three dwelling units, sprinklers are required unless separated with fire-walls.

Not in all jurisdictions. We do not require sprinklers if it is 8 dwelling units or less so it is good the ICC does not assume everything is srinklered in all sections.

I agree Table 1021.1 does not come into play very often but it is where you start if there is only one exit from a story.