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3 story room VS 3 story atrium

IBC defines atrium as "An opening connecting two or more stories other than enclosed stairways, elevators, hoistways, escalators, plumbing, electrical, air-conditioning or other equipment, which is closed at the top and not defined as a mall. Stories, as used in this definition, do not include balconies within assembly groups or mezzanines that comply with section 505."

The OP says that the room in question is surrounded by other stories with glazing on all sides but no balconies or openings. This sounds like an atrium to me.

The high school locker room adjoining a 30 ft. high gym a couple posts earlier wouldn't be an atrium unless there were other floors adjoining the gym.
 
Gee, seems like you're a little cocky for just joining this forum. If you are so sure of yourself, provide the code reference that you are so sure of.

We've explained ourselves and indicated how it does not meet the definition of an atrium nor a multi-story space. Put some effort into a response, don't just demean others.
Gee, seems like you're a little cocky for just joining this forum. If you are so sure of yourself, provide the code reference that you are so sure of.

We've explained ourselves and indicated how it does not meet the definition of an atrium nor a multi-story space. Put some effort into a response, don't just demean others.

@Ty J. Demeaning other people's answers was not my intent so I apologize if it came across that way. I'm sure you weren't making fun of other people's answers as well or being sarcastic or demeaning in any way with your responses and questions, correct? I took your question in earnest and I answered directly with no embellishments.

Others in this post have also explained and indicated how it does meet the definition of an atrium so I don't think I'm the lone dissenting voice here am I?

I'm loathe to have to repeat myself or others in this subject that have even cited the code verbatim but if it helps, here are some IBC sections for reference:

Chapter 2 Definitions - [BG] Atrium
Chapter 4 Special Detailed Requirements Based on Occupancy and Use -
Section 404 Atriums.
Section 404.5 Smoke Control.
Section 404.6 Enclosure of atriums.
 
@Ty J. Demeaning other people's answers was not my intent so I apologize if it came across that way. I'm sure you weren't making fun of other people's answers as well or being sarcastic or demeaning in any way with your responses and questions, correct? I took your question in earnest and I answered directly with no embellishments.

Others in this post have also explained and indicated how it does meet the definition of an atrium so I don't think I'm the lone dissenting voice here am I?

I'm loathe to have to repeat myself or others in this subject that have even cited the code verbatim but if it helps, here are some IBC sections for reference:

Chapter 2 Definitions - [BG] Atrium
Chapter 4 Special Detailed Requirements Based on Occupancy and Use -
Section 404 Atriums.
Section 404.5 Smoke Control.
Section 404.6 Enclosure of atriums.
Nope, I was not being sarcastic or demeaning. You....definitely come across as arrogant.

Again, not to rehash, but the proposed does not meet the definition of an atrium. Key word from the definition of an atrium is "connect". As no connection is made, there is no atrium.
 
Nope, I was not being sarcastic or demeaning. You....definitely come across as arrogant.

Again, not to rehash, but the proposed does not meet the definition of an atrium. Key word from the definition of an atrium is "connect". As no connection is made, there is no atrium.

@Ty J. I'm glad I got it correct and you were not being sarcastic or demeaning so I'm glad I honored that by replying to your question then.
That I came across as arrogant in my reply... well, I can deny that I'm arrogant but who am I to say how I made other people feel is real or not. I cannot.


If your biggest hang up on why it cannot be an atrium is because of "connect/ connection" then let us change tact here.

1. First thing's first, I believe what we can all agree on is that the OP presented a multi-story building with at least 3 stories. If we don't agree about this then there's no point in further discussions.

2. I am hoping we can still agree that a part of the building which will be the "wall climbing" area will be 3 stories high with the rest of the building around it being 3 stories of gym.

At this point, I suggest you visualize an atrium in section.

Building Section.png

The 3 floors/stories adjacent to the wall climbing area are physically connected to it.

There's the connection.

You can enclose the atrium so that there's no mechanical/HVAC connection or "communication" between the floors or the atrium but that just deals with passage of smoke based on Section 404.6.

It is still an atrium... an enclosed atrium.
 
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@Ty J. I'm glad I got it correct and you were not being sarcastic or demeaning so I'm glad I honored that by replying to your question then.
That I came across as arrogant in my reply... well, I can deny that I'm arrogant but who am I to say how I made other people feel is real or not. I cannot.

If your biggest hang up on why it cannot be an atrium is because of "connect/ connection" then let us change tact here.

1. First thing's first, I believe we can all agree that the OP presented a multi-story building with at least 3 stories. If we don't agree about this then there's no point in further discussions.

2. A part of the building which will be the "wall climbing" area will be 3 stories high with the rest of the building around it being 3 stories of gym.

At this point, I suggest you visualize an atrium in section.

View attachment 6626

The 3 floors/stories adjacent to the wall climbing area are physically connected to it.

There's the connection.

You can enclose the atrium so that there's no mechanical/HVAC connection or "communication" between the floors or the atrium but that just deals with passage of smoke based on Section 404.6.

It is still an atrium... an enclosed atrium.
May be physically connected, but if it is not atmospherically connected, I do not believe it is an atrium.

The "chimney effect" that provides the hazard in an atrium is due to the fact that the products of combustion (smoke and heat) pull fresh oxygen rich air from the lower levels and push into the upper floors. With the proposed design, the smoke and heat will rise, but have nowhere to go.

Yes, it would be smart to use fire resistant construction on the abutting walls of the multistory portion adjoining the rock climbing area. And lets be real, 90+% of jobs will use 5/8-in Type X throughout, so there will most likely be a 1-hr wall already. An atrium only requires a 1-hr fire barrier anyway (404.6).
 
May be physically connected, but if it is not atmospherically connected, I do not believe it is an atrium.

The "chimney effect" that provides the hazard in an atrium is due to the fact that the products of combustion (smoke and heat) pull fresh oxygen rich air from the lower levels and push into the upper floors. With the proposed design, the smoke and heat will rise, but have nowhere to go.

Yes, it would be smart to use fire resistant construction on the abutting walls of the multistory portion adjoining the rock climbing area. And lets be real, 90+% of jobs will use 5/8-in Type X throughout, so there will most likely be a 1-hr wall already. An atrium only requires a 1-hr fire barrier anyway (404.6).

Can you please point me to what part of the code is stating that being "atmospherically connected" is a requirement for something to qualify as an atrium? That is where you've lost me.

Yup, you got the chimney effect which is why there is that need for smoke control so that the heat and smoke will actually have somewhere to go regardless of if there is a fire barrier or not (unless there are only 2 adjacent floors which is an exception to having a smoke control system...).

As for Section 404.6, it talks about enclosing an atrium with glass enclosure... exactly as OP described. There is nothing there that talks about the atrium ceasing to be an atrium after it is enclosed. It talks about how a fire barrier can be eliminated though.

Section 404.6 Enclosure of atriums.
Atrium spaces shall be separated from adjacent spaces by a 1-hour fire barrier constructed in accordance with Section 707 or a horizontal assembly constructed in accordance witgh Section 711 or both.
Exception:
1. A fire barrier IS NOT REQUIRED where a GLASS WALL forming a smoke partition is provided.
The glass wall shall comply with all of the following:
1.1 Automatic sprinklers are provided along both sides of the separation wall and doors, on the room side only if there is not a walkway on the atrium side. The sprinklers shall be located between 4 inches and 12 inches away from the glass and at intervals along the glass not greater than 6 feet. The sprinkler system shall be designed so that the entire surface of the glass is wet upon activation of the sprinkler system without obstruction;
1.2 The glass wall shall be installed in a gasketed frame in a manner that the framing system deflects without breaking the glass before the sprinkler operates; and
1.3 Where glass doors are provided in the glass wall, they shall be either self-closing or automatic-closing
3. A fire barrier is not required between the atrium and the adjoining spaces of up to three floors of the atrium provided that such spaces are accounted for in the design of the smoke control system.
 
Can you please point me to what part of the code is stating that being "atmospherically connected" is a requirement for something to qualify as an atrium? That is where you've lost me.
IMG_0321.jpg
 
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I am working on a mixed use building. 3 stories of which is planned to be a gym with a climbing wall. We would like to avoid an atrium designation for the climbing wall area. The climbing wall is to be three stories and I am proposing putting the climbing wall in it's own three story room. The room would have glazing on all sides with an entrance at the bottom of the wall, but no other balconies or entrances from the other floors. I see this as a room that just happens to be three stories. We are trying to avoid the smoke evacuation system that is required with an atrium because it will be difficult and cost prohibitive. Am I barking up the right tree? I am wondering if the walls would need to be fire rated? I assume they would have to be smoke barriers.




When Judy comes back,

If she would do a simple elevation of this, and make it into a link, post the link here.

It might clear up atrium or not an atrium

Deal or no Deal
 

Thanks for providing this commentary. It really makes it clear that there is no connected atmosphere requirement in relation to floors adjacent horizontally to an atrium.

This commentary is explaining the physical characteristics of what an atrium is. It is talking about the "environment" - the setting or conditions in which a particular activity is carried on - of adjacent stories vertically in relation to each other.

There are two reasons why I understand it to be this way:
1. It talks about floor opening or a series of floor openings. It doesn't talk about wall openings or any horizontal openings.
2. It doesn't talk about "atmosphere" - the air in any particular place - specifically atmosphere of adjacent stories horizontally to the atrium.

So stories that are normally stacked together and separated by floors are now connected to each other. They are connected through floor openings that connect what was individual environments of each story into one environment which becomes the atrium.

"The definition identifies that an atrium is a FLOOR OPENING or a SERIES OF FLOOR OPENINGS that connects the ENVIRONMENT of ADJACENT STORIES."
 
Thanks for providing this commentary. It really makes it clear that there is no connected atmosphere requirement in relation to floors adjacent horizontally to an atrium.

This commentary is explaining the physical characteristics of what an atrium is. It is talking about the "environment" - the setting or conditions in which a particular activity is carried on - of adjacent stories vertically in relation to each other.

There are two reasons why I understand it to be this way:
1. It talks about floor opening or a series of floor openings. It doesn't talk about wall openings or any horizontal openings.
2. It doesn't talk about "atmosphere" - the air in any particular place - specifically atmosphere of adjacent stories horizontally to the atrium.

So stories that are normally stacked together and separated by floors are now connected to each other. They are connected through floor openings that connect what was individual environments of each story into one environment which is the atrium.

"The definition identifies that an atrium is a FLOOR OPENING or a SERIES OF FLOOR OPENINGS that connects the ENVIRONMENT of ADJACENT STORIES."
Guess we will just agree to disagree. I stand by my interpretation.

If the spaces are do not have a connected environment (an atmospheric connection by my read), then it is not an atrium.
 
The code commentary rabbit hole... Commentary Figure 404.6(1) and Commentary Figure 404.6(2)… Enclosure of Atriums... one showing atrium closed to adjacent floors beside it... the other showing atrium open to adjacent floors beside it. Both atriums according to the code and the code commentary...

atrium1.png atrium2.png
 
The code commentary rabbit hole... Commentary Figure 404.6(1) and Commentary Figure 404.6(2)… Enclosure of Atriums... one showing atrium closed to adjacent floors beside it... the other showing atrium open to adjacent floors beside it. Both atriums according to the code and the code commentary...

View attachment 6631 View attachment 6632
Shows balconies that have openings (doors to access them), not walls.
 
All of your diagrams in post 36 have one thing in common: some type of balcony connecting the office floors to the high bay area. Thats not what Judy had described.
And yes, you do come across as arrogant and confrontational.
 
All of your diagrams in post 36 have one thing in common: some type of balcony connecting the office floors to the high bay area. Thats not what Judy had described.
And yes, you do come across as arrogant and confrontational.

Wow. My old friend pops up again. How are you doing? I hope you are well. Not sure if my arrogance changes the validity of my opinions or data I have shared but you are welcome to present your observations.

It's very interesting how you like to call people out here and I'm the confrontational one.

Got it. Thanks.
 
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Shows balconies that have openings (doors to access them), not walls.

It's your choice to ignore and not address the part about floor openings and how mezzanines and balconies are not really a prerequisite for a space to be an atrium as noted and addressed in detail on the IBC definition and commentaries.

Your understanding of terms and definition of words are also clearly different from some of us here.

Live and let live. Thanks for the difference in point of view. I sincerely appreciate it. There's always something to learn not only from people who agree with you but especially from those with counter points.
 
For the record....I'm still with Enri...You could argue that the "environment" is not shared with operable doors and windows that are not depended on for HVAC purposes...And what if the RTU on the 3 story gym supplies air to the rest of the building? Is it an atrium then?
 
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