Ceiling mass considerations, help needed.

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Adonikam
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Joined: Mon Jan 25, 2021 9:25 pm
Location: Melbourne, Australia

Ceiling mass considerations, help needed.

Post by Adonikam »

Hi,

I've been a long time reader of this forum but first time poster, this place is a absolute treasure trove of information and I want to start by thanking everyone that has posted here over the years.

I've been managing a large rehearsal studio (16 studios) for 7 or 8 years, unfortunately we have to close our doors due to Covid, but with sad endings come new beginnings. I've taken it upon my self to build a new studio in its place just down the road. Working there for as long as I have, I think I've got a pretty good idea of what worked, what didn't and what could be improved.

Now to the nitty gritty...

Since I am building the structure from scratch I'm facing a plethora of engineering issues that honestly I'm not equipped to deal with. Obviously I will be consulting with a structural engineer but I want to have the most clear idea of what I want beforehand, for clarity for those who will later become involved in the project and because it helps me budget. I've been studying the timber framing code of Australia to the best of my ability and think I've done a pretty good job sticking to to it with my design. Enter the ceiling.

Unless I'm totally misunderstanding something, which is highly likely, the framing code dictates the ceiling will weigh no more than 12.5kg/m2 without special considerations. I cannot for the life of me find out anything beyond that. My ceiling could weigh up to 36kg/m2 across a 4.8mx6m frame, not including cloud absorbers and PA I plan to suspend from ceiling as well. All span tables for ceiling joists are also penned out under the assumption of 12.5kg/m2, I've been digging for something rated higher but to no avail.

Does anyone have any advice here? I would rather avoid consulting with a draftsperson or structural engineer with something that has to be totally redesigned, it is going to end up a rather large facility and while I have some money to play with in my budget, I want to have the best idea possible of the costs beforehand. Also if my entire frame up until this point needs to be redesigned to cater for an improved ceiling, it is something I'd rather sketch out myself.

I can post pictures of the Sketchup model I've done if it will help, but I'm more just looking for something I can read to get a general idea of what needs to be done to support the weight. To be honest I am very surprised it isn't an issue that arises more frequently, which makes me suspect I'm missing something blatantly obvious.
gullfo
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Re: Ceiling mass considerations, help needed.

Post by gullfo »

large spans with large mass = structural engineering. that said, you might need to construction it using i-beam steel framing for the bulk of the work, then short spans between them.
Glenn
Adonikam
Posts: 3
Joined: Mon Jan 25, 2021 9:25 pm
Location: Melbourne, Australia

Re: Ceiling mass considerations, help needed.

Post by Adonikam »

Thank you for the reply, I've contacted a few structural engineers for a consultation. I hadn't really considered the use of steal or I-beams seems but it seems I can probably make it work. Appreciate the assistance.
Adonikam
Posts: 3
Joined: Mon Jan 25, 2021 9:25 pm
Location: Melbourne, Australia

Re: Ceiling mass considerations, help needed.

Post by Adonikam »

After doing some digging I've found this is probably the best way to go, pending a engineer actually contacting me back.

In my original design I had two frames totally decoupled with rather large airpocket between, though that was with a purely timber frame. That idea seems kind of unfeasible now knowing I probably have to use steal beams, in terms of cost and space limitations. Now I guess I will have to pin my sheething directly to either side of the frame rather than have two separate ones which I'm sure will diminish isolation qualities... Very much in uncharted territory for me now.

I guess now I'm asking does anyone know of any examples of this kind of build I can reference? Or any papers/documentation to read through? I'm suddenly feeling like I'm walking in the dark now.

I had also planed for a contingency of if I need to move location for what ever reason (upsize, downsize, no lease renewal ect) I could just detach the individual walls and ceilings, load them onto a truck then reattach and reseal without a full rebuild. But it is now starting to look rather... permanent, which I'm sure the landlord would also sh*t bricks over. Maybe it's back to the drawing board on this idea.
gullfo
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Location: Panama City Beach, FL USA
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Re: Ceiling mass considerations, help needed.

Post by gullfo »

one trend - mixing @ home - use existing rooms with treatments. track at recording studio designed for the sound levels you anticipate would exceed what you'd get at home.

depending on how the rooms were done, the landlord might find it a value-add assuming it could be re-used as residential or commercial space. of course all the in-room treatments etc could readily be designed to move.
Glenn
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