Problem Ceilings

[bobgaggle]

My theatre is a small black box space with an 11' ceiling. The ceiling is made of plaster and has some hollow space above it (we think its suspended from concrete beams that support the floor above). Recently I've been considering covering the entire ceiling above the playing space with 3/4" ply. I usually have to attach something to the ceiling for every show (christmas lights, tree branches, streamers etc), and my usual methods are proving ineffective. I've tried using standard screws but they usually tear out and I don't want to risk anything falling on someone. Lately I've been using wall anchors and bolts, which are highly effective but my ceiling is starting to look like the surface of the moon.

We do have some unistrut arranged in a kind of grid that can be used to hang things, but for specific points I always have to put an anchor in. I figured the ply would be a great way to simply screw in whatever set dec I need.

Does anyone have experience with anything like this? Did you get your ceiling rated by a pro to see if it could even bear the weight? Maybe ply isn't the way to go and there is a better solution. Thoughts?

 

[avkid]

Learn how to repair plaster, then attach to your heart's content.

 

[MPowers]

You need to find out just what the existing ceiling is and how it is supported. What would your attach plywood to??? Would the existing structure support the weight of the plywood? 3/4" ply weighs about 75# per 4x8 panel. A 3 panel wide by 5 panel deep (24' x 20') ceiling would weigh over 1,000# . In addition, what is the weight of the thing you will add? (doesn't sound like much, but does need to be considered. )

You say you hang things from the ceiling all the time? Maybe a false ceiling is the right answer, maybe not, but a long term solution does seem to be in order. Remove the plaster ceiling and install a hanging grid? Remove and install a pipe grid? Just some possible solutions.

 

[FatherMurphy]

The plaster ceiling may or may not be considered part of the fire rating of the room, so you might want to check with your friendly neighborhood fire marshal before tearing into anything, or permanently skinning the ceiling with something flammable (although flame retardant plywood does exist).

If you were to permanently mount a series of pipes or struts going in one direction (L/R or Upstage/Downstage), a temporary add-on pipe or strut perpendicular to the permanent ones should allow you to locate any point you need over the stage.

Anything you add permanently, or temporarily, is a load on the overhead building structure, so you really should involve an engineer and see what he says you can safely support. The guys who work in ones and twos out of small independent offices usually aren't very expensive (probably just a few hundred bucks for something like this), and it's money well spent for the peace of mind.