Building a band platform?

[Anonymous067]

I need to possibly (within budget) assemble a platform type system (around 16' x 16') for use at a church for a "raised platform" stage.

I only want to raise it up about 2' max.

I have seen platforms build in the HS I got to, and they're just unsafe and crappy honestly. I know how houses are built, and wouldn't feel safe walking on the platforms built in our theater.

I'm guessing to just go with the standard 8'x4' platforms, shoved together and tied together with OSB on top going the opposite direction...
Built on the bottom with 2x6 lumber?

Any special considerations to take?

 

[shiben]

If your willing to only build it 1' high, which is what our church has, you can frame the deck out of 2x12s and then cover the top with 3/4" plywood. This can then be painted or covered in carpet, which is what we did. Framed it on 12" centers, and its rock solid. We made ours 10'x10', but I suppose you could do 8x8 or something too.

 

[jwl868]

You should be able to manage with 2x4s. I built a couple 4' x 4' by 18" high platforms with 2x4 frame and I think 3/4" plywood. Very sturdy, to say the least. (You may want to consider some sort of step up.)

And check out this thread (but I didn't create the thread).

http://www.controlbooth.com/forums/scenery/5191-my-platform-system.html

Joe

 

[Van]

The thread mentioned in the previous post is a good place to start for research. I would throw a few questions back at you:
Is this a temporary system? do you plan on putting it in and taking it out ?
The main reason I ask this is the possibilty of building code compliance issues if it is a permenant install

How many people are going to be on it?
Total load is a big issue in the engineering of any platforming system and one of the reasons you might run into code compliance issues.

If your looking for a system than can be removed and replaced, I'd suggest a triscuit system < which actually exceeds most building code load limits.> with a set of pony or knee walls to support the triscuits. Well either way you should probably build ponies to suppot the deck.

 

[derekleffew]

You people with your fancy newfangled, carbon-fibre, Bluetooth-enabled systems! The way it's always been done (and that every text on theatrical scenery describes):

Build 8- 4'x8' platforms and leg them to two feet.

Per platform (multiply by 8):
1- 4'x8' x3/4" Plywood CDX or better (particle board, OSB, not acceptable)
2- 2x4x 7'-9" "Stiles"
2- 2x4x 4'-0" "Rails"
3- 2x4x 3'-9" "Toggles"
6- 2x4x 1'-11 1/4" "Legs"
~36' total of scrap 1x2 or 1x3 as diagonal bracing (each between 2'-6" and 3'-0" long)
~50 6d common nails for above
~50 8d common nails to attach top to frame
~20 16d common nails to attach framing members together
3- 3/8x 3 1/2" Carriage Bolts with Nut and washer to attached platforms to each other
12- 3/8x 3 1/2" Carriage Bolts with Nut and washer to attach legs
OR
6- Leg-A-Matic™ brackets (Preferred, especially if legs will be removed for storage or height changes, but added cost.) and hardware

One should definitely plan on step units of two or three steps each, and probably kick rails and possibly hand rails.

 

[ship]

Back in college I had a similar question of how a 4x8 platform could be rated for a 50# live load given two or three toggle, and three quarter plywood glued and screwed to a 2x4 frame when in a house you needed at least 2x6 lumber for say a 30# live load 16" on center for about that span. This much less out of college I was building platforms with 5/4 lumber.

The teachers couldn’t sufficiently explain it to me at that point so I went into personal study into how and why.

Don’t persay remember sufficient to that studying of texts what I found in satisfying me much less it was similar to a later study into corrugated flooring in how something so light a gauge supports loads and dpans, much less in detail of why perhaps not appropriate to say so in easy answer provided.

Perhaps instead more time should be spent researching the how and why on the engineering side because the hard found answer to it will be useful later on similar problems. Many and most might disagee with some things are needed to research and study on one's own to get it properly. Still though that's how I learned and I'm hoping what I found useful by way of lots of study would be found useful also for you given the below.

On the other hand for a perminant install I probably would go with more like what you are thinking or wooden truss system, only check your span and spacing between posts concepts because 2x6 assuming normal platform legging won’t get you there either for perminant install.

P.S. dont' forget sway braces for the legs, 18" requires sway brace be it triangular plywood for the leg or lumber bracing this unless a truss work support structure that already includes it. For this as it were deck, look more into how one would design a deck for a perminant install for what size of lumber supporting it and the spacing.

Joe[/QUOTE]

 

[Van]

I'll second what ship said, with a height of 24 inches you need to be sure to cross brace the legs to counter the sheer forces.
Step wise you can get away with a "two-stepper" , one unit with 2 8" steps this will equal a total of three 8" steps when butted up to the deck. Building code calls for no greater than 7" rises but 8" is quite common onstage.
A note on Dereks post; The picture shows legs that are Chamfered this is always a good idea for platform legs, and especially useful when installing a deck over carpet.

 

[Anonymous067]

On a different note...

What are those staging platforms called, they're metal braced on the bottom (pre-assembled), usually a black "carpet" material on the top...?

 

[cprted]

Risers? Wenger has a variety to choose from ...

Wenger Corporation | Staging Systems

 

[derekleffew]

Similar to these, Blah067?

:: Steeldeck, Inc.
Usually use pipe legs? I've used them a zillion times, but never knew the manufacturer. I call them trussframe risers.

Two of the best manufactured-riser companies are StageRight and Staging Concepts.

 

[museav]

I agree with Van regarding factoring in whether it is portable staging or permanent construction and the potential for code issues. I know a lot of churches that have had to tear out brand new DIY platforms due to code issues that they could have identified up front. Also, since it is for a band then it not only has it be quiet when people walk on it, but ideally would not resonate or otherwise affect any instruments on stage. You also may want to consider how you access under the stage for cable pulls, etc.

Some of the DIY solutions shown look very nice, however I would hesitate to use any kind of staging for any particular application without having some engineering calculations or test results for the load ratings. There may be a big difference between something that works for a few skinny models to stand on for a fashion show and something you can roll a grand piano across or set choir risers on top of.

 

[Van]

Resonance is an issue that should be counted. The link to Gaff's thread has a very good solution in that he installs homosote or Builder board under the plywwod this is a great way to dampen sound.

 

[museav]

Resonance is an issue that should be counted. The link to Gaff's thread has a very good solution in that he installs homosote or Builder board under the plywwod this is a great way to dampen sound.

However, that is often not sufficient for bands with bass amps, kick drums, etc. on stage and the potential benefit of any constrained layer approach is typically reduced by screwing through both layers and by any heavy point source loads. For floor applications Homasote is typically placed on top of the plywood subfloor and attached with screws and adhesive, then whatever finish floor laid on top of the Homasote. Laying a material like Homasote on top of the frame and then perimeter screwing the subfloor over it may actually be of minimal benefit. Also, although they offer a Class I or A rated N.C.F.R. Homasote material, the common Homasote Sound Barrier 440 material has a Class III or Class C flame spread rating and thus may not be acceptable for use in public assembly spaces.

You might get better results from making the basic structure very stiff and as heavy as possible and then placing soft goods on top or having a floating top layer. Vibration isolation pads on the bottom of the legs may help with minimizing vibration transfer to the building structure. And adding acoustical absorption in the stage cavity can also typically help.