Platforms

[OldGrover]

The second last play I was doing carpentry for, we had to build a platform, 5 feet in the air, to act as a balcony. We needed stairs up and down to it, both onto the stage and off. What I ended up doing worked, but I am wondering if there was a better way, more standard way. The requirement was that everything we built was reusable and thus storable.

We took a standard 4 x 8 riser and used that as the main platform. We built a similar platform, 2.5 x 5 as well. To raise them to the 5' height, we built L shaped legs - cut a 2 x 6 and a 2 x 4 for each leg, glued and screwed them them together, so that we had an L measuring 5 1/2 inches each side and 5' high. I bolted a leg to the four corners of each platform and, with the 4 x 8 platform, put a simple 2 x 6 leg in the midpoint, just for paranoia's sake, meaning it had 6 legs. 4 braces, one on each side, also bolted, ran diagonally to keep it square and to prevent it from tipping over and collapsing. The two platforms were then bolted together and the stairs added. The stairs, since they also needed to be collapsable, consisted of a standard 2 x 4 wall the width of the stairs, framed on 12 inch centres, again for paranoia. We cut two stringers for each actual stair case and built them as a separate unit, with treads and risers permanently installed. The stair unit was then bolted to the 2 x 4 wall and additional 2 x 4's run from the bottom of the wall to the bottom step, giving the unit stability. Those staircases were then bolted to the risers, making a solid unit that was then filled in with thin ply and curtains, the lot painted black. It made a tremendously solid unit, using up a huge number of heavy bolts. It worked well and stores reasonably well, but I'm wondering if there was a better way to do it. I'll have to build another one in a show or two.

The unit went together like this :

I used, of course, code specced rise over run for the stairs and the upper platform had a solid railing.

Thoughts? How would you have done this? Briefly, the requirements were 1> reusable 2> portable (since it was built elsewhere) 3> storable 3> a 4 x 8 platform with stairs onto stage and stairs that lead off stage so they could appear from offstage onto the platform and leave from the platform to go offstage

-OG

 

[ship]

Don't wait for me to reply on it, I replied off line in length as might be expected and not here in the hopes also of seeing how others do this or what they think.

 

[Peter]

No one at my school is ambitious enough, or has enough time to attempt somthing like this! A few years ago we did a play, Anne Frank I belive, that was supposto have an upstairs loft/balcony type thing, and the director just ended up having that room be out on the apron way to one side of the stage. It worked, but it was a pain to light, and was not as cool as a real elevated room would have been. (It didnt really make sense when the actors kept saying they would go up to this room, and they really went down and toward the audience!)

 

[ship]

Theater - a suspension of disbelief

It's often best not to attempt what the director did not feel comfortable with doing safely. Even if shorting you in some form of construction experience, he did not provide you with a bad example either. Probably a wise choice even if harder to light.

 

[Peter]

Yep, in the end, I more enjoy doing lights and sound anyway. My dad was a carpenter for a long time so i am semi-familar with basic construction skills, and the other benifit of living in such a rural area, noone else really knows what a play is supposto be like, so I can get away with a lot ya, i know this is good and bad, but I have to work with what I have.

So how would everyone else do this? (I hope this isnt going to have to turn into one of those threads where the same people have to just keep posting so it stays near the top of the list and alot of people read it )

 

[OldGrover]

Obviously, I've already posted how I DID do it. In construction, that'd be 'post and beam'. I suppose you could also do it with a frame wall design - basically, build a house under a platform - 2 x 4s, 18 inches oc, frame construction walls around all sides. That'd be /serious/ overkill, though, I suppose, if you wanted to use the space under the platform you could frame out windows or doors or whatever. For munchkins, since we're talking about a 5 foot platform

You could also use solid 4x4 posts instead of the 2x4 and 2x6 L construction I used. The L is far easier to bolt into, though.

For what it is worth, the only difficult bit of this build was the stairs. The actual raising of the platform was fairly cheap (3 2x6x10's, 5 2x4x10's) and quite simple to build, providing you already have a nice solid riser.

Hmm. One issue we /did/ have was that it wasn't very quiet. Not surprising, of course, and it wasn't that bad simply because of the mass of the thing once it was all bolted together. But how could we dampen it?

-OG

 

[tenor_singer]

A good book to invest in...

I have a book that shows how to build decks. It has a very useful chart in it that tells you safe spans for 2x4, 2x6, 2x8 etc... lumber. They also have some very good plans for rectangular and square shaped spans. I will have to look up the ISBN, but I kept the book simply for the load charts. I bought it at Lowes.

Hope this helps!

Tenor

 

[ship]

Lots of schools of thought on sound dampening. I grew up in the days of all paltforms and stair units being faced by muslin in covering carpet padding of horse hair type. Worked fairly well but was not very cost effective especially when repairing rips. I moved onto the school of thought that all platform frames needed to be covered by 1/2" black celous fiber insulation, than the plywood was added, than the 1/4" tempored hard board. Interesting method, not very sound resistant, but always promissed job security when the top ripped apart from the frame. Somewhere in between that came the carpet and carpet padding that was more or less half hazzardly added to the underside of a platform in between the framing members. This padding helped some to absorb the sound - at least more than the Celotex did but not much and it was always tearing off especially when in the way for adding legs. Nothing like crawing under a 16" platform amongs moldy carpet padding. Only one step up from the caseen paint cabinet.

In any case, the manufactured wall type assemblys have the advantage I never had. Those skinned 2" sheets of foam faced on both sides by plywood would certainly be strong and quieter. Could almost do platforms just with them without a frame under them. These "Stress Skinned Panels" than would be my choice of a way to go. After that, perhaps renting a industrial spray foam machine for the day and foaming the under carriage of a platform might have some effective usage.

For a perminant platform, I might look into using fiberglass insulation batting. Fiberglass turns sound by way of vibration into heat. It with air gaps and dissimilar material thicknesses is a major factor into such things as sound booth design.

Easiest perhaps is to lay the stage, cover it with celotex fiber or some form of foam insulation, than cover it with 1/4" to 1/2" plywood depending upon the point loading upon it. Same with the stairs though if an enclosed stair case, perhaps fiberglass will work well given you can adhere it well to the step.

 

[OldGrover]

Interesting. I may be able to score some free fiberglass batting and could probably rig up a way to mount it, even in a temporary situation. My only concern with that would be getting the dust and the strands over everything. Hmm. Yes, much better in a permanently mounted configuration. I wonder if I could build a frame within the riser to permanently cover the batting while still leaving the corners free to attach the legs. That'd work, but then, I suppose, people'd complain about the weight. Can't win

Should we build new risers (doubtful, we have a fair number of these ones and we got 'em cheap) I'll look into building in the foam, as you suggested with the manufactured wall. That's a great idea and I don't know why I didn't think of that - I've seen enough This Old House where they use them

Hmmm. Spray foam. I wonder if it'd actually absorb enough to be useful. You could also get that liquid foam that you can mix, I suppose. Turn the risers over, pour between the members. Hope like hell it doesn't expand too much and tear your riser apart

Thanks for the thoughts.

-OG

 

[ship]

The two part mixture is the same stuff as you would rent with the machine only in a much larger format. Normally it's a 3:1 expansion mixture as opposed to a 2:1 mixture from the can. As for adhesion, you must not have used spray foam much.... stick your hand in it for a moment and some staining from the foam will be on your hand for a week. Sticks to anything that's why they call it both adhesive and insulation.

I kind of think that spraying it as backing onto your stair case if built right will work very well given a sufficient thickness to dampen the reverb of the sound.


Another similar idea might be spray on flame proofing as is used on the steel structure for sky scrapers. Given there is lots of studies about 10 years too late to save me about some harmful asbestos like effects of this stuff currently going on, and it blew off the steel from the World Trade Center in not protetecting it from anything, still it or a similar industrial spray on flame proofing as a fibrous material might be effective when at normal thickness in also dampening sound.

A no doubt less effective means might also be to once the stairs are built perhaps laminate - what is it... 3/4" ceiling tile fibrous material to it, than face it with say a 3/8" plywood to absorb sound. This than in the celous fiber material as long as it don't get wet, absorbs sound some and in having dissimilar thicknesses of plywood, prevents the glass effect of vibration repeating itself. Won't stop the echo effect as much but it should dampen the walking on it sound some. Just a question with it or 1/2" Celotex of making your frame sound before you attempt to layer this on, instead of using it between frame and top.

 

[nate]

the rule we usually use is "if it works and is good enough for government work, then it is perfectly fine" along with that we ues "if it aint broke, dont fix it". it sounds like you did a good job with the platform.

 

[soundman]

Well I have to do somethign like this for a class project, granted the height was 6' not 5' but the concepts still remain the same. I dont understand the point of hte small platform, was it to act as a landing?

Heres how to make the platform 6' tall (for this case just subtract afoot from the middle, the banding will still be 8" from the floor.



as far as the whole layout it seems like thats the way to go.