Uh. Yeah, my design does have an overhead element to it. It doesn't extend as far out into the space, but I had to check, and sure enough, there is a sprinkler head directly above the space.
It makes for some changes in the design. It screws up the lighting concept that I had planned because the overhead has windows and there is no way to block them, and that means I lose control over the lighting completely. Considering what a lighting wonk I am, that's a hard hit to take.
I do have an idea that I think will work, but it is a compromise. It's something that had I known in advance, I probably would have changed the design for, so lesson learned.
Then there's flameproofing, or more precisely, the application of a flame retardant. That's actually not nearly the problem that the sprinkler clearance is; I can mix the chemicals into the paint base (though oddly I had to change it from the PVA undercoat because the fire retardant chemicals actually react with the PVA to polymerize and make slime).
The lighting change makes for another issue on the interior. That may or may not be a good thing; I can probably turn it into a positive.
Tonight is gonna be busy. There is a bunch of foam cutting that needs to happen, but that may get pushed off to tomorrow pending weather-- isolated thunderstorms forecast tonight. If not cutting, I'll be detailing the cuts for some of the other pieces.
I am behind schedule. At this point I wanted to be done with the base construction, and I am not. I think it's a safe bet that my social life from here through the convention is pretty much a non-starter.