mezzanine question....what happens when...

[nicbro]

I'm working on this project in a multi-user building. My tenant is a retail store that uses the first floor as retail and warehouse. The second level (half the total sq ft of the space) is used for business. My conundrum come in on the second level. It seems to have been originally permitted as an enclosed mezzanine, which under the VA is allowed to be 1/2 the total floor are of the room/space it occupies. The second level has two paths of exit access, one empties into the middle of the retail area below and is unrated. The second one is an enclosed staircase, unrated and exits directly outside. Somewhere along the line, another mezzanine was added to the warehouse so the aggregate area exceeds 50% of the current footprint. The tenant wants to add another mezzanine that connects the office portion mezzanine to the warehouse mezzanine. I garner that at some point in the past the suite was perhaps larger and that perhaps the aggerate area of the mezzanine was 50% or less but was demised at some point and what maybe once met code, no longer does. The occupant load of the office portion and common path of travel meets the requirements for a story with one exit. If I rate the enclosed staircase walls that exits directly outside, does anyone see a problem with calling this a second floor. My other problem comes in that the tenant does not have the information on occupancy/use and area of the other tenants to show the AHJ that it meets height and area. Any suggestions?

 

[walker.t]

My other problem comes in that the tenant does not have the information on occupancy/use and area of the other tenants to show the AHJ that it meets height and area. Any suggestions?

If the building is existing, why would the building department need information about the other tenant spaces in the building? I would have assumed that when each of those tenants moved in that the building department would have confirmed that any height or area limitations were met. If the building department really needs this information, the building owner should be able to give you information on the areas of all the other units and what uses they contain.

 

[walker.t]

which under the VA is allowed to be 1/2 the total floor are of the room/space it occupies.

Forgot to ask, what is “VA”? Construction type V-A? To what code provision are you referring when you say that the maximum area for an enclosed mezzanine is 50%? The only provision I see making a reference to 50% is 505.2.1 Exception 2 but that applies to construction Type I and Type II if they are sprinklered and have an emergency voice/alarm system, but this provision doesn’t say anything about the mezzanine being enclosed.

 

[Yankee Chronicler]

I would need to see plans before attempting to answer. The first question is whether these "mezzanines" are mezzanines under the code. A lot of designers (architects, PEs, and unlicensed building designers alike) seem to be fond of tossing out the 'M' word in situations where it absolutely does not apply.

 

[nicbro]

Forgot to ask, what is “VA”? Construction type V-A? To what code provision are you referring when you say that the maximum area for an enclosed mezzanine is 50%? The only provision I see making a reference to 50% is 505.2.1 Exception 2 but that applies to construction Type I and Type II if they are sprinklered and have an emergency voice/alarm system, but this provision doesn’t say anything about the mezzanine being enclosed.

VA refers to the Virginia Building Code. I need everyone else’s use and area because I need to determine if what was one considered a mezzanine, and I now want to classify as second floor meets area limitations. I wouldn’t normally care about what it was considered, but because they want to add another mezzanine and they are already over 50%, trying to figure out a way to do it.

 

[nicbro]

I would need to see plans before attempting to answer. The first question is whether these "mezzanines" are mezzanines under the code. A lot of designers (architects, PEs, and unlicensed building designers alike) seem to be fond of tossing out the 'M' word in situations where it absolutely does not apply.

I certainly wouldn’t classify it as a second floor as it has no rated exits. I’ll attach a floor plan next time I’m at my computer.

 

[walker.t]

VA refers to the Virginia Building Code.

Thank you, didn’t even think about that but makes sense seeing as you are located in Maryland.

I’ll wait to see your plan before offering other comments.

 

[Yankee Chronicler]

I certainly wouldn’t classify it as a second floor as it has no rated exits. I’ll attach a floor plan next time I’m at my computer.

Respectfully, that the wrong way to approach it. Step one is to determine whether or not it's a mezzanine (or two mezzanines, or three mezzanines). It sounds a lot to me like it's actually a story.

Once you determine whether it's a story or a collection of mezzanines, THEN you investigate whether it/they have means of egress complying with the code for a story or for a collection of mezzanines.

You seem to be laser focused on just the area of this upper level. There's more to it than that. The IBC 2021 definition of "Mezzanine" is:

[BG] MEZZANINE. An intermediate level or levels between
the floor and ceiling of any story and in accordance with
Section 505.

So, by definition, it has to be an intermediate level within a story. That means we also need to look at the definition of "Story" -- and then we have to look at section 505.

[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.

Now we have to see what section 505 has to say:

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).

505.2.1 Area limitation. The aggregate area of a mezzanine or mezzanines within a room shall be not greater than one-third of the floor area of that room or space in which they are located. The enclosed portion of a room shall not be included in a determination of the floor area of the room in which the mezzanine is located. In determining the allowable mezzanine area, the area of the mezzanine shall not be included in the floor area of the room.

Exceptions:

1. The aggregate area of mezzanines in buildings and structures of Type I or II construction for special industrial occupancies in accordance with Section 503.1.1 shall be not greater than two-thirds of the floor area of the room.

2. The aggregate area of mezzanines in buildings and structures of Type I or II construction shall be not greater than one-half of the floor area of the room in buildings and structures equipped throughout with an approved automatic sprinkler system in accordance with Section 903.3.1.1 and an approved emergency voice/alarm communication system in accordance with Section 907.5.2.2.

Bottom line: Irrespective of labels, a mezzanine is an elevated level WITHIN a room or space. The maximum aggregate area of ALL mezzanines within one room or space cannot exceed one-third (not one-half, unless Virginia meddled with this section) of the room or space (not story) within which the mezzanine(s) is/are located. If you can't define that an elevated level is clearly an elevated space-within-a-space, IMHO it's a story rather than a mezzanine.

I have had this argument with more than two design professionals. My state building inspector has consistently agreed with my view of how it works.

 

[walker.t]

I have had this argument with more than two design professionals.

Starting with the applicable definitions then going to the section on mezzanines doesn’t leave them much room for argument.

 

[Yankee Chronicler]

Starting with the applicable definitions then going to the section on mezzanines doesn’t leave them much room for argument.

Well, there's a saying among attorneys: "When the facts are on your side, argue the facts. When the law is on your side, argue the law."

In the most recent of these little confrontations, the design professional (who is a PE who likes to practice architecture even though he is neither licensed nor qualified to do so) fell back on the strongest argument he had: "I'm a licensed engineer ... and you're not. You are not qualified to dispute what I say."

That was several months ago. We still haven't issued that permit. The owner has hired a different design professional.

 

[walker.t]

In the most recent of these little confrontations, the design professional (who is a PE who likes to practice architecture even though he is neither licensed nor qualified to do so) fell back on the strongest argument he had: "I'm a licensed engineer ... and you're not. You are not qualified to dispute what I say."

Wow, that’s crazy. I’ve always assumed that giving the building department attitude was a sure fire way to make plan review more difficult.