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Is a Mezzanine considered a "floor"?

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Meadowbend99

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Jan 30, 2017
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Location
Houston, TX
I have a client doing an aerial gym, under 5,000 SF (w/ mezzanine). They are wanting to put in an open mezzanine to increase their square footage with redundant apparatuses. They'll be A-3, under 12,000 SF and under 300 occupants. They do not want to add a sprinkler system. Per sprinkler requirements for A-3 "The fire area is located on a floor other than a level of exit discharge serving such occupancies" would they be required to add a sprinkler system? Per the definition of a mezzanine "An intermediate level or levels between the floor and ceiling of any story" makes it sound like it is not considered a "floor". If it is considered a floor, would an exterior exit stair from the mezzanine be adequate. Using 2015 IBC and IFC.
 
Meadowbend99 said:
I have a client doing an aerial gym, under 5,000 SF (w/ mezzanine). They are wanting to put in an open mezzanine to increase their square footage with redundant apparatuses. They'll be A-3, under 12,000 SF and under 300 occupants. They do not want to add a sprinkler system. Per sprinkler requirements for A-3 "The fire area is located on a floor other than a level of exit discharge serving such occupancies" would they be required to add a sprinkler system? Per the definition of a mezzanine "An intermediate level or levels between the floor and ceiling of any story" makes it sound like it is not considered a "floor". If it is considered a floor, would an exterior exit stair from the mezzanine be adequate. Using 2015 IBC and IFC.
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How many sq. ft will the mez be?
 
The footprint of the building is 3,500. They would like the mezzanine to be 1500 SF, but to be 1/3 of the space it would need to be 1,050 SF.
 
If it is a mezzanine per the requirements of Section 505, then is is part of the story below, which is presumably the level of exit discharge. See Section 505.2 as follows, with the key statements in red.

505.2 Mezzanines
A mezzanine or mezzanines in compliance with Section 505.2 shall be considered a portion of the story below. Such mezzanines shall not contribute to either the building area or number of stories as regulated by Section 503.1. The area of the mezzanine shall be included in determining the fire area. The clear height above and below the mezzanine floor construction shall be not less than 7 feet (2134 mm).
 
Meadowbend99 said:
The fire marshal had indicated to my client that a sprinkler system was required for a mezzanine.
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Have you checked the local municipal codes for amendments? Perhaps they have a stricter requirement for sprinklers than the default IBC requirements.
 
I assume you're using the occupant load factor for "Exercise rooms." There is no requirement in the IFC or the IBC that requires mezzanines to be sprinklered. However, if you read the requirements for Group A-3, Condition 3 states "The fire area is located on a floor other than a level of exit discharge serving such occupancies."

Notice that it does not use the word story. Yes, a mezzanine is not a story, but it is a floor, and it is located above the level of exit discharge. Refer to the Commentary, which states "The text does not make reference to 'story' but uses the term 'floor,' which could include mezzanines and basements."
 
RLGA said:
I assume you're using the occupant load factor for "Exercise rooms." There is no requirement in the IFC or the IBC that requires mezzanines to be sprinklered. However, if you read the requirements for Group A-3, Condition 3 states "The fire area is located on a floor other than a level of exit discharge serving such occupancies."

Notice that it does not use the word story. Yes, a mezzanine is not a story, but it is a floor, and it is located above the level of exit discharge. Refer to the Commentary, which states "The text does not make reference to 'story' but uses the term 'floor,' which could include mezzanines and basements."
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Ron, I agree with your reading of IBC 903.2.1.3, particularly the use of the word floor in place of story.

However, I have in the past, not required sprinklers for an A-3 or other use with similar language in Ch. 9 because of the following language from Ch. 5.

505.2 Mezzanines
A mezzanine or mezzanines in compliance with Section 505.2 shall be considered a portion of the story below. ... (continues)

The leading statement of IBC 505.2 indicates that a mezzanine is considered a portion of the story below. The definition of 'level of exit discharge' (below), also uses the term story.

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

My contestation is that the mezzanine is a separate floor that does contribute to fire area, but it is not an additional story. It is in fact, a portion of the story it is constructed within. Therefore, as a portion of the ground level story, the mezzanine is on the level of exit discharge, and does not trigger IBC 903.2.1.3 #3.
 
That is a plausible interpretation. Note that the Commentary states "...could include mezzanines..."

I guess what I'm really saying is that the fire marshal's interpretation as presented by the OP is not an invalid interpretation (assuming that is what the fire marshal was using as their justification).
 
I think I am more on board with Ron on this....as fire area is usually a sprinkler driver and the mezz is specifically a fire area....specific > general...?
 
steveray said:
I think I am more on board with Ron on this....as fire area is usually a sprinkler driver and the mezz is specifically a fire area....specific > general...?
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So are you in favor of sprinkling a 5000sf building because it has a 1050sf mezzanine (mezzanine is not on the same floor level as the level of exit discharge)? Fire area is only 6050sf; half of the threshold area established by IBC Section 903.2.1.3?

That is the OP's question...
 
I disagree. It is quite clear that the mezzanine is included in the fire area.
It is also quite clear that a mezzanine is not a story, it is an intermediate area between stories. If this was just a raised area of 5 or 6 feet it would not be a mezzanine yet it would still be on the level of exit discharge
IBC 505.2
The area of the mezzanine shall be included in determining the fire area.

[BF] FIRE AREA. The aggregate floor area enclosed and bounded by fire walls, fire barriers, exterior walls or horizontal assemblies of a building. Areas of the building not provided with surrounding walls shall be included in the fire area if such areas are included within the horizontal projection of the roof or floor next above.

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

[BG] 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.

[BG] MEZZANINE. An intermediate level or levels between the floor and ceiling of any story and in accordance with Section 505.
 
In my opinion, it is not the area of fire area driving the sprinkler system, it is the location of the fire area, which includes the floor elevation of the mezzanine. When there is a Group A-3 on a floor (not a story) that is above the level of exit discharge, then a sprinkler system is required. The mezzanine is a "floor" and the level of exit discharge is at the floor level below (even though the mezzanine is part of that story). ClassicT provided one interpretation that is possible and I've provided another interpretation that is possible--this is just an extremely gray area of the code.
 
Tim Mailloux said:
what is an Aerial gym? is this like gymnastics?

will they ever hold competition at the gym?
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It's a gym that will use silks and lyras(rings). They also have pole dancing classes. So there are specific fixed apparatuses for each person with fairly sizeable clearances. In the main room they'll have 20 spots for silks (2,000 SF), but I know the FM is concerned with what happens if they remove the apparatuses so we'll need to calculate as if there isn't fixed equipment, so more like 40 occupants for that room. They wouldn't hold competitions with spectator seating but they'll have showcases on occasions and they should be able to handle that since their occupant load will end up being quite a bit more than what they can actually handle.
 
Meadowbend99 said:
...the FM is concerned with what happens if they remove the apparatuses so we'll need to calculate as if there isn't fixed equipment...
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This irritates me to no end. You can say that about ANY building: "What if they move this wall?" "What if they take out all of the fixed seating?" etc.

In this case, the use is still "Exercise"; so if the equipment is there or not, fixed or moveable, the occupant load factor is what it is.
 
IBC 505.2.1 indicates an increase in size from 1/3 to 1/2 if suppression and voice alarm. Honestly I never looked at it from Ron's perspective, I have always considered floor and story to be interchangeable in this section. Could it be that since the post indicates the desire was to have a mezzanine larger than 1/3 that is why the fire official said sprinklers required? Would 505.2.1 need to indicate that sprinklers are required for a larger mezzanine if they were required in the first place?
 
As to Access" how will the mezzanine be accessible?
Also if the bldg is sprinklered the underside of the mez would also then require sprinks, no?
 
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