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What would you do? Occupant load distribution

  • Thread starter Thread starter Sifu
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The plan says 500 fixed seats. I can't imagine how even the dumbest of design professionals can put on the same page "500 fixed seats" and "441 occupants." That takes a very special level of incompetence.
I guess they are requesting an increased occupant load based on 1004.5.1. Of course that section requires that all other code requirements are met since the egress path from neither the stage rear or theater has the required capacity to handle all the occupants from all the other spaces that empty into it.
 
32" rows are going to make people scream. But the code problem is going to be dead end aisles. Hard to imagine with 32" row spacing there will be the extra aisle access way width to accommodate the crossover required beyond 5 rows dead end.
I can't locate this 5 row limitation for dead aisle accessways in the 2021 IBC or ICC 300.

They don't provide any details for the telescopic seating other than in the specifications for them, which refer to shop drawings and that they be compliant with ICC 300. Based on the pretty pictures, they wouldn't comply in areas such as aisle accessway width, CPET and aisle width, but they are only providing this schematic, and nothing more to verify compliance.
I think all front row is allowed in bleachers, which is why I asked if these were retractable. Some conditions allow it. But I generally think this is poor design, and I haven't even seen the section.
Section? You mean a section view of the telescopic seating? It sure would be nice to see that.
 
There's a separate standard for telescoping bleachers: ICC 300. It's a referenced standard under the IBC, unless your jurisdiction deleted it in adopting the IBC.
 
There's a separate standard for telescoping bleachers: ICC 300. It's a referenced standard under the IBC, unless your jurisdiction deleted it in adopting the IBC.
Well aware, and they tell me it will comply but don't demonstrate any of it. Based on the info I have it won't comply, but the info is so generic and incomplete I can't really tell for sure. They spec several suppliers for it to be bid to comply with it with their shop drawings, but that apparently hasn't been done yet. They are deferring it, but they don't list it as a deferred submittal. I'm OK with it but they need to have it as an approved deferred submittal so that any approval (tacit or otherwise) is not construed as an approval of that element.
 
I can't locate this 5 row limitation for dead aisle accessways in the 2021 IBC or ICC 300.
I might not have been clear but longer dead end aisles require wider aisle accessways so people who can't use that aisle - blocked by fire or other - can move through the aisle access way - row - to the other aisle.

I understand you don't have complete design info. This is one area I agree with Yankee Chronicler, that the documents should be complete enough to review for code. Somehow requiring things like aisle width to comply with code in the spec seems very weak.

I'll look in 300 - I'm on that committee - and point to the dead end aisle requirements I was referencing. Hosting my 19 month old grandson for a few days and hardly finding time to look at Internet. Way to old to chase toddlers.
 
I understand you don't have complete design info. This is one area I agree with Yankee Chronicler, that the documents should be complete enough to review for code. Somehow requiring things like aisle width to comply with code in the spec seems very weak.

Back when my state used BOCA, the section in chapter 1 about construction documents included something to the effect that "Citing this code or language such as 'as required' shall not be a substitute for specific information." That went away when we got the ICC codes. I complained back when the first IBC came out, and I was told by ICC staff that the "intent" remained the same, and that I should just cite section 107.2.1. Which, of course, is a cop-out. We always get push-back, regardless of how nebulous the plans are.

So I got the State to amend the code when we adopted IBC 2021. We put back language saying that citing the code or using language such as "as required" is not a substitute for providing specific information.

And, even with that language in the code, we STILL get push-back.
 
I might not have been clear but longer dead end aisles require wider aisle accessways so people who can't use that aisle - blocked by fire or other - can move through the aisle access way - row - to the other aisle.

I understand you don't have complete design info. This is one area I agree with Yankee Chronicler, that the documents should be complete enough to review for code. Somehow requiring things like aisle width to comply with code in the spec seems very weak.

I'll look in 300 - I'm on that committee - and point to the dead end aisle requirements I was referencing. Hosting my 19 month old grandson for a few days and hardly finding time to look at Internet. Way to old to chase toddlers.

IBC 1029.6.

And IBC 1029.1.1 refers to ICC 300 for bleachers.
 
I might not have been clear but longer dead end aisles require wider aisle accessways so people who can't use that aisle - blocked by fire or other - can move through the aisle access way - row - to the other aisle.

I understand you don't have complete design info. This is one area I agree with Yankee Chronicler, that the documents should be complete enough to review for code. Somehow requiring things like aisle width to comply with code in the spec seems very weak.

I'll look in 300 - I'm on that committee - and point to the dead end aisle requirements I was referencing. Hosting my 19 month old grandson for a few days and hardly finding time to look at Internet. Way to old to chase toddlers.
They have the width provision in 300, same as the IBC for fixed seats. Both also have the same provisions for the CPET. In this case they would need 12" + .6"x6, so 15" for the dual aisleways. But, they don't tell me if the seats are seats, benches, have backrests, etc. They only show a picture which looks a lot like individual fixed seats but the spec is for telescopic seats. Maybe that is the only graphic they had, maybe they are providing telescopic seating with individual seats (the Google has pictures of such things). Either way, using their graphics they only have 12" when scaled. Even the number of seats they propose could be off since if benches the length will change the number from what they have depicted. I see dead-end provisions for aisles, but not aisle accessways in both the IBC and ICC 300, but that may be irrelevant since the aisle access ways are pretty limited to begin with?

I am going to ask for the information I need to determine the overall MOE requirements for the spaces and buildings. When they get it on record and the deferred submittal isn't consistent with it they they can cross that bridge then if I haven't jumped off of it yet.
 
Assuming this is permitted to be constructed using ICC 300, I was wrong. The IBC requires increased aisle access way width when the dead end aisle is more than 20' (7 rows at 32"). ICC 300 doesn't require the additional aisle access way width until after 16 rows. There are 18 rows in your drawing so those last two do require a wider aisle access way than the other 16, around 20" versus 12".

I think this is wrong and poor design, that just by providing assembly seating "that are not building elements" you can have much less egress capacity, but based on what you have shared the assembly seating portion seems to comply with code.
 
Still a lot of problems with this setup, but this one in particular continues to confound me.

Look back to the plan at post #13. They have made some changes in distribution, but the question remains. The stage OL requires 2 exits. There is one out the back, and the other (two) off the front of the stage. The theater seating side has an OL of 500, with two exits (500 is the increased OL based on the number telescopic seats as the worst case).

Section 1006 is where we determine the number of exits from any space. 1006.2.1 requires the number of exits based on the design occupant load of any space and tells us the cumulative OL is determined by 1004.2. 1004.2.1 tells us to combine the OL from the accessory or intervening space. The seating space is 500 but larger when combining the intervening or accessory space. The number of exits required is 2 for the seating side alone, but 3 when combining. Three exit access doors are provided if the stage is counted. If the exit path from seating side across the stage is compliant am I done? Does the distribution of OL need to add occupants to the stage exit and in turn can they remove OL from the front seating side exit access?

The stage REQUIRES the use of the seating side for compliant exiting. The seating side does not REQUIRE the stage unless you count the people from the stage. Seems like a circular argument.

Essentially we have two spaces requiring two exits, in one large space demised only by the stage level. Egress travel can flow in either direction if needed. Is all that is needed is to have compliant paths in both directions with a reasonable distribution of occupants?
 
Take a look at Section 410.5.1 to see if that answers your question.
The stage has 3 exit pathways. One out the back, one on each side of the front of the stage. It is the OL from the two front pathways that I am questioning, which is whether they must be added to the OL from the seating side, thus requiring the seating side to have a 3rd exit path back across the stage. If so I don't see it as a problem except that they don't want an obvious path with lighted exit signs, and because if they contribute any additional occupant load out the back they will then overload that exit path.
 
Just from a planning and use point of view, you could reverse swings on dressing room doors and that is could be second stage moe. It also provides utility for using the stage, being able to enter at either side from backstage.

I am surprised that the seat count of the telescopic seating is the maximum, compared to it being stored and the entire area being used as assembly without fixed seats - standing with an OLF of 5 SF.

Never have seen a stage with 161 occupants designated E occupancy either but shouldn't change anything.
 
The resubmittal changed a lot so the drawing snippet is no longer completely accurate as I originally posted it. They designate it wrong...in a way. During school hours the stage and egress path has a higher occupant load than during the after hours use because there are classrooms that will use the exit path off the rear of the stage. Their claim is that the theater could be used during school hours, only for school occupants so they keep it an E for school use. During after hours, they don't designate it (but will on the next submittal) it will be designated as A1. They also came back with loose chairs at 7-net and took out circulation at the perimeter. This is why the seat count for the telescoping seats is higher.

By your response can I take it you would determine that the three exits are sufficient for the spaces as long as the three exits are code compliant? For understandable reasons, they don't want an open, signed exit path across the stage to be visible from the audience side, but I don't know how else their design could work without rearranging the space. Below is the latest iteration, showing the after-hours use. It is the exit path from the audience side across to the back of the stage where they show no exit path, no markings, no contributing occupant load that causes these questions. (highlighted by the yellow box) You can see the occupant load being contributed from the stage to the audience, but none from the audience side to the stage.

1747335734779.png

The different scenarios for during school and after school are confusing at best. But, the scenario for during school use is that the stage would be in use by students and staff, with no audience. The scenario for after hours use is that the stage and audience would be in use, but no classrooms at the rear of the stage (not shown). Since they will have no student OL from those areas during after-hours use they could distribute load from the audience side to the rear and probably keep the exit path compliant, then it just becomes the obstructions and marking that are the issue. I think. Acceptance of those scenarios are subject to approval by the CBO and FM as operational controls. I'm just trying to get it to a point where I and they can understand it and would meet code if they accept it..
 
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