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3 story room VS 3 story atrium

Judy Bethuy

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Joined
Apr 29, 2020
Messages
1
Location
Detroit, Michigan
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.
 
Not an atrium person,,,

My question for clarification,,,

Before you turn this donkey into an elephant

If once this is built, you walk in and it is a one story gym say in 75 % of the building,,,,

But at the end the ceiling goes say up 30 feet. No floors or platforms anywhere above ground level,

If you want to and could build it that way,,
Without calling it an atrium

Would you be happy?

Because if you do, someone will correct me, I think you can do that set up
 
If you put it in its own room, not atmospherically connected to the other rooms in the building, then it is not an atrium, and it is not a 3 story room. It is a very tall one story room.

If, on the other hand, all the other floor levels open into the gym (for example, with balconies so that someone can stand and watch the climbers), then it sounds more like an atrium.
 
I agree with Yikes and CDA...

As Yikes indicated, you'll want to use the proper verbiage. Try indicating that it is a room with ~30-ft ceilings that does not communicate atmospherically with other stories.
 
ATRIUM. 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.

Kind of sounds like an atrium to me....Remember that an atrium is not necessarily "open" to the other stories and is required to be enclosed by definition...

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 with Section 711, or
both.
 
ATRIUM. 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.

Kind of sounds like an atrium to me....Remember that an atrium is not necessarily "open" to the other stories and is required to be enclosed by definition...
But where does it connect multiple stories? If it does not provide connection, then it is not by the definition, an atrium.

With no intermediate floor or roof construction in the room with the tall (~30-ft) walls, an additional story is not created.

STORY. That portion of a building included between the upper surface of a floor and the upper surface of the floor or roof next above (see "Basement," "Building height," "Grade plane" and "Mezzanine"). A story is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost story, from the top of the floor finish to the top of the ceiling joists or, where there is not a ceiling, to the top of the roof rafters.
 
If it or the adjoining space catches fire, unrated walls would burn out and allow the fire to spread to multiple stories. 1-hour rated construction is to prevent this.

Smoke control is only required when there are openings that communicate atmospherically with other stories.
 
So if she designs it so it slopes

From say 1 1/2 story level to 3 story level,,,

Am I an atrium?

No upper floors onto the upper level, just wide open building.
 
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.

@Judy Bethuy Based on what you describe as a 3 story space, it appears to still be an atrium even if you enclose it with glazing and its own entrance.

You don't need to have any fire barriers though as long as you comply with the exceptions of Section 404.6 which you might have already looked at.

What we can't determine from the information you gave is where is this atrium in relation to the rest of the building as well as its size or geometry. I bring this up because depending on where it is, you may explore the idea of passive smoke control system which would be more cost effective than a mechanical system.

Good luck.
 

Well there's the IBC definition and there's the proportion and geometry of things.

Here are the general forms of an atrium:
(a) Centralized
(b) Semi-enclosed
(c) Attached
(d) Linear
Four-different-general-forms-of-atrium-a-Centralised-b-Semi-enclosed-c-Attached.png
 
So given a PEMB with high-bay ceilings that has one end with an interior framed 2nd floor. The high bay (your image C) is an atrium then? I think not.

Would you really classify this space below as an atrium?

upload_2020-4-30_13-55-23.jpeg
 
You beat me to the reply
You m
So given a PEMB with high-bay ceilings that has one end with an interior framed 2nd floor. The high bay (your image C) is an atrium then? I think not.

Would you really classify this space below as an atrium?

View attachment 6624

No I would not classify it as an atrium and I would refer you back to IBC as to why not.

Once you get over that, you begin to understand the special danger of the atrium being addressed is that it can function as a chimney in a way because of the stack effect potentially endangering the adjacent floors that butt up against it. Hence it having to be addressed specifically in the code and not lumped in with basketball courts or warehouses for example... both of which as you know are dealt with separately by the code.
 
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So I walk out of high school locker room, into a basketball court with thirty foot ceiling,,, Atrium??

I walk out of a locker room into a ice hockey arena with thirty foot ceiling Atrium???


https://dissolve.com/stock-photo/Indoor-ice-hockey-royalty-free-image/101-D145-220]

No, you would know that walking out of a locker and onto a basketball court does not make the basketball court an atrium because you’d know better after checking the code which you’re good at.

If the logic which you are hanging your hat on about the original poster's situation not being an atrium is due to your understanding that the rock climbing area with the 30 foot ceiling is a space that does not connect adjacent stories... hence it is not an atrium... sure that would be correct if it indeed was not adjacent to several stories.

However, as I read the original post..The words "3 stories"and "other floors" are mentioned. Not sure why she would go to the trouble of specifically mentioning "3 stories" and "other floors" if it wasjust a gym with an area that is taller than the rest at 30 feet. She specifically says "3 stories" with the rock climbing area taking up 3 stories in height by itself and that it was enclosed with glass but would have no openings to other floors. So my understanding then... and others here as well it would seem... based on what was described and the IBC definition is that it is an atrium.

We can agree to disagree on how we read the original post and maybe the original poster can clarify it when she chooses to.
 
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I would refer you back to IBC as to why not.

Once you get over that, you begin to understand the special danger of the atrium

because you’d know better after checking the code which you’re good at.

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.
 
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