Mezzanine accounting for 12% of the open area in a room, while 15% of floor area of the room

[sunyaer]

This is a screenshot from a building code advisory from the city of Regina on mezzanine. In example #2, in room #2, the enclosed mezzanine is indicated as 12% of the open area while 15% of the floor area (of the room). It doesn't make much sense to me, as the way I understand, the percentage of a mezzanine to the open area of the room should be greater than the percentage to the floor area ( since floor area of a room is larger than the open area). Would the percentages indicated be a typo, or there is scenario where the percentages are correct?

https://www.dropbox.com/s/iv6vw00fnl4u08m/12 % of open area 15% of floor area.jpg?dl=0

 

[Inspector Gadget]

At quick glance, I think the intent here is that the mezzanine itself is 12 per cent of the room area, but that 15 per cent of the mezzanine floor area is is enclosed, so even though the mezzanine is small, the enclosed area exceeds the 10 per cent threshold, therefore it has to be treated as a storey.

 

[sunyaer]

At quick glance, I think the intent here is that the mezzanine itself is 12 per cent of the room area, but that 15 per cent of the mezzanine floor area is is enclosed, so even though the mezzanine is small, the enclosed area exceeds the 10 per cent threshold, therefore it has to be treated as a storey.

I understand the intent, while the 15 percent is not indicating the percentage of the mezzanine floor area which is enclosed. The blue legend indicates the whole mezzanine is enclosed mezzanine. whose area is 12 per cent of the open area in the room where the mezzanine is located, and 15 percent of the floor area of that room. The code analysis path looks like this: 1. compare the mezzanine area to the open area of the room; 2. since it's enclosed, check if its area is greater than 10% of the open area of the room;

My question is actually only about the figure 12% and 15%, where the percentage of a mezzanine to the open area of the room where it's located should be greater than the percentage of the mezzanine to the floor area of the room, since the open area of a room is smaller than the floor area of that room, am I correct or am I missing something?

 

[Jay Smith]

Based on the other rooms, that most likely says 1.5% rather than 15%.

 

[tmurray]

Open mezzanines can be 40% of the open area of the room they are in.
Closed mezzanines can be 10% of the floor area of the suite.

We allow larger open mezzanines because it maintains communication between the the mezzanine and the remainder of the room, minimizing delays in communication during an emergency. We contrast this with closed mezzanines, where we expect the delay in communication, and have a much more restricted size allowance.

It really doesn't matter how big the room a closed mezzanine is located in. Where it is an enclosed space, you could have it being 100% of the size of the room it is superimposed over and the issues remain the same.

With open mezzanines, be cautious about enclosing below the mezzanine. It would take away from the room area.

 

[sunyaer]

Based on the other rooms, that most likely says 1.5% rather than 15%.

Zooming in to look at the image closely, though the image is a bit blurry, yes, it appears more like 1.5% (the "1" and "5" spaced a bit apart, indicating there is a "." dot in between) rather than 15%.

A perfect finding.