# Outdoor amphitheater



## ThatOneGuy (Mar 7, 2021)

Hi all,
My first time designing an outdoor amphitheater and just wanted to get some opinions if I'm on the right track. I know, ask the AHJ... But this is just an initial pass so any feedback would be appreciated. Using IBC 2015.

The project will look something like THIS or THIS. Not my images, just something to get the idea across. It will be primarily for small concerts in a county fair type setting, but permanent construction. The stage itself including roof overhangs would be roughly 2,000 SF with backstage stuff like green rooms, loading dock, etc. adding roughly 3,000 SF so the entire building would be about 5k. Proposed stage construction is CMU block walls, steel roof structure, concrete floors. Audience area is all benches or lawn seating totaling around 1,400 occupants by calculation, probably less in real life.   

Chapter 4 - special requirements for stages and platforms
Confirmed with the client there will be NO "_overhead hanging curtains, drops, scenery, or stage effects other than lighting and sound_", so technically this is a _platform_ not a _stage_ as defined by Chapter 2. Therefore, the majority of this section's requirements do not apply. That includes sprinklers, fire-rated proscenium walls and curtains, fire-rating between the stage and dressing rooms, etc.
   This is actually one of the parts I'm the least familiar with. For example, 410.7 says "_Stages _shall be equipped with an automatic sprinkler system [...]" but does not mention _platforms_ at all, so it shouldn't be required. Have I got this right?

Occupancy type A-1
I looked at A-5 for "viewing outdoor activities" But that didn't seem right for the intended use? I also looked at THIS thread from someone with a similar project who was considering a mixed-occupancy A5 and A3 building? Again that seems to be not the correct application here. The only thing that's bugging me is the actual uses within the building are entirely production and performance, with the audience area not included in the "building use" since they are exterior. Would that make this an A-3 instead? 

Chapter 9 Sprinklers, required where one of the following:
1. > 12,000 SF (nope)
2. Occupant load > 300 (Not in the building itself, the seating is all outdoor)
3. multi-story (not applicable)
4. multi-theater complex (nope)

Construction type II-B, well within allowable heights and areas for non-sprinklered buildings. So based on ch. 4, 5, and 9 no sprinklers required.

Chapter 10 Means of Egress - The MOE for the stage and greenroom areas are pretty simple and should not be a problem. I know I need to check stage accessibility but there's room for a couple of ramps and stairs to deal with elevation changes and the occupant load will be pretty low. MOE for the seating area should qualify as _smoke-protected assembly seating_ since it's open to the sky? So I'd follow those requirements to figure out aisle sizes and whatnot, right?

I think that's all the big-picture items. Again, I'd appreciate any general feedback or any red flags or pitfalls you've seen on similar projects that I should watch out for.


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## cda (Mar 7, 2021)

I could see A-5

I would say no, you do not meet the definition, plus do not have to worry about it


*SMOKE-PROTECTED ASSEMBLY SEATING. *Seating served by _means of egress _that is not subject to smoke accumulation* within or under a structure.*


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