Suspending a Ceiling Frame from Steel Joists?

[rosestudios]

How would I go about hanging a ceiling consisting of a wooden frame and 2 layers of 5/8" drywall with green glue from a ceiling that has metal joists? I looked on the inside of my ceiling and it's essentially steel beams strapped to the building's I-beams and then a layer of drywall attached to that. The beams seem thin, like hat channel (but thicker than this) and I'm not sure what these are exactly called.

I do not have the ability to tear down the existing drywall so I was hoping to hang a new ceiling supported by the walls I've built out in the room. How do I attach to the metal joists so that I can use wire and neoprene and spring hangers to create a decoupled frame? Is there a way to simply build the frame on top of my walls?

Thanks for the help.

[Soundman2020]

It would help if you posted a diagram and photos of what you have, and a diagram of what you want to do. Normally, the inner-leaf ceiling rests only on the inner-leaf walls, not touching the outer leaf wall or the outer-leaf ceiling at all. Is there a reason why you can't do that?

- Stuart -

[xSpace]

How do I attach to the metal joists so that I can use wire and neoprene and spring hangers to create a decoupled frame? Is there a way to simply build the frame on top of my walls?

Thanks for the help.

Sounds to me like you are about to do two things...if not three.

1 is that you are going to create a three leaf design with known LF issues.

2 is that you are about to attempt to hang a known amount of weight(after considered specs are seen) from an unknown dead loaded system that has already settled.

3 you are going to introduce flanking with this wire, neoprene and hangers.

Why can you not simply develop the ceiling, uncoupled to the exterior strcuture, that rests on your framed interior structure, that is a fully decoupled assembly by anyone's measure.

[rosestudios]

I'm just concerned about weight loading, at most my studio design requires a ceiling frame spanning 14 ft at the longest points, although it becomes shorter as my room curves in, would a 2x4 frame placed on the wall frames be capable of supporting two layers of 5/8" drywall?

You cannot safely span and carry multiple layers of sheet goods across a fourteen foot span with 2 X 4. Also Like I said earlier, if you attach it in any way to the existing structure you have to:

1: Make certain the existing structure can carry the load.
2: Make certain you do not introduce flanking via the support system.

I was using suspension for extra support...but do the neoprene and spring hangers not provide enough decoupling for the flanking to be considered taken care of? See attached image for diagram of studio.

None at all. In fact they are at odds with each other. Your MAIN issue is gravity, span and what dimensional lumber should I use. Problem in a span like this is that the assembly will warp due to gravity and flex according to the TL it is trying to contain.

This is also a potential health hazard if improperly implemented and might not get covered what-so-ever on your home insurance.

Then we have to consider the existing overhead floor system. It sounds like you have a sheathed ceiling and you want to introduce another hard boundary. Now you have a multiple hard boundary with multiple air spaces, known to reduce transmission loss in the lower frequencies.

You do not want to do that either.

P.S. Should I be consolidating my two active threads?

It is always better.