# Large Stair unit - Best way to build?



## kjones9999 (Mar 13, 2017)

Hi all-- in the process of designing a stair unit--

The top tread will be at 88" height and will be 48" wide-
The bottom Tread will 16' wide. Tread depth is approx 1 foot. So basically I need 10 1 foot platforms. Its a big pyramid.

My thinking was to build a series of individually supported 2 foot platforms and have the intermediary step placed on top of that - But is there a better way to support the platforms than individually? If the treads weren't so deep I would consider stringers. But those would seem more trouble than they are worth here.

Any thoughts? These need to be rock solid as they will support 10-12 people at times.


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## Van (Mar 13, 2017)

Do they need to move on and off stage? Why not simply build them as a framed staircase unit?


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## kjones9999 (Mar 13, 2017)

Van said:


> Do they need to move on and off stage? Why not simply build them as a framed staircase unit?


Sorry - -I should have mentioned that....

They will be permanent -- attached to a large platform that does not move.


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## TheaterEd (Mar 13, 2017)

Off the top of my head, I would buy two of these and chop the top two steps off. Mount them on the far sides of your bottom 1' x 1' step. Then just add 2 x 12 treads and frame out the sides with 2 x 4 s for vertical supports and add luaun facing. If I get bored running sound for this rehearsal I'll draw something up.


Edit: Here is where I got before the end of their rehearsal.


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## kjones9999 (Mar 13, 2017)

TheaterEd said:


> Off the top of my head, I would buy two of these and chop the top two steps off. Mount them on the far sides of your bottom 1' x 1' step. Then just add 2 x 12 treads and frame out the sides with 2 x 4 s for vertical supports and add luaun facing. If I get bored running sound for this rehearsal I'll draw something up.
> 
> 
> Edit: Here is where I got before the end of their rehearsal.View attachment 14519




I really appreciate you doing that -- I am so sorry for being so non specific... The base will be 16 feet -- Do you think I could expand the idea?


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## Van (Mar 13, 2017)

kjones9999 said:


> I really appreciate you doing that -- I am so sorry for being so non specific... The base will be 16 feet -- Do you think I could expand the idea?


Easily, if @TheaterEd doesn't get a chance perhaps I can throw together an example for you. Are the edges of the staircase curved/swept?


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## Jay Ashworth (Mar 13, 2017)

Just a reminder here:

(I would) make sure each step is individually supported, not in any way supported by steps further down. An installation contractor screwing that up was the root cause behind the Kansas City Hyatt disaster in the 90s.

I'm not sure that's applicable here, but some designs might go that way, so I figured I'd point it out.


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## kjones9999 (Mar 13, 2017)

Van said:


> Easily, if @TheaterEd doesn't get a chance perhaps I can throw together an example for you. Are the edges of the staircase curved/swept?



No its very much like what TheatreEd had drawn, just inverted and wider.


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## kjones9999 (Mar 13, 2017)

Jay Ashworth said:


> Just a reminder here:
> 
> (I would) make sure each step is individually supported, not in any way supported by steps further down. An installation contractor screwing that up was the root cause behind the Kansas City Hyatt disaster in the 90s.
> 
> I'm not sure that's applicable here, but some designs might go that way, so I figured I'd point it out.



Thats a good point. Do you think it would be dangerous if two steps were on the same support?


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## Jay Ashworth (Mar 13, 2017)

kjones9999 said:


> Thats a good point. Do you think it would be dangerous if two steps were on the same support?


Not as long as the support knew it was coming. 

The problem in KC was that 2 decks were supposed to be supported from a threaded rod, independently. What got built was that _the lower deck was supported from the upper deck_, and the nuts weren't up to the load of both decks; Wikipedia has lots of nice detail.


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## BillConnerFASTC (Mar 13, 2017)

Jay Ashworth said:


> Not as long as the support knew it was coming.
> 
> The problem in KC was that 2 decks were supposed to be supported from a threaded rod, independently. What got built was that _the lower deck was supported from the upper deck_, and the nuts weren't up to the load of both decks; Wikipedia has lots of nice detail.



It wasn't the nuts so much as the eccentric loading. I had a long conversation with one of the experts that investigated it. The relevant lesson was that it was designed correctly, and then the designers were let let go - to save money - and the contractors changed the detail. Even though they were not paid to review submittals or the actual work, the designers were sued and lost and went out of business. Second lesson, beware of design build contracts. Much better to have design eyes on the work than just the contractor's who's number one concern is their profit.


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## Jay Ashworth (Mar 13, 2017)

https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse


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## BillConnerFASTC (Mar 13, 2017)

kjones9999 said:


> Hi all-- in the process of designing a stair unit--
> 
> The top tread will be at 88" height and will be 48" wide-
> The bottom Tread will 16' wide. Tread depth is approx 1 foot. So basically I need 10 1 foot platforms. Its a big pyramid.
> ...



88" - 10 treads - 8.8" per rise? This is a dangerously high step. Normally 7" maximum is considered the highest rise permitted, and research shows falls diminish a lot at around 6.4 to 6.5". In other words 7" is not good design, but code maximum. Good design is in the 6.5" range. 8.8" is in the range of check your liability.


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## Van (Mar 13, 2017)

BillConnerFASTC said:


> 88" - 10 treads - 8.8" per rise? This is a dangerously high step. Normally 7" maximum is considered the highest rise permitted, and research shows falls diminish a lot at around 6.4 to 6.5". In other words 7" is not good design, but code maximum. Good design is in the 6.5" range. 8.8" is in the range of check your liability.


This however, is a Scenic piece and not open to the Public.


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## BillConnerFASTC (Mar 13, 2017)

Van said:


> This however, is a Scenic piece and not open to the Public.


Did you forget OSHA? And if it's occupied - by performers or technicians or the public - it is required by law to meet building and fire codes. The person's means of egress at the middle of those stairs is either up or down those stairs and law requires every occupant be provided with a means of egress.


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## Jay Ashworth (Mar 13, 2017)

Ob:


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## manuallyfocused (Mar 13, 2017)

If you have extra depth to work with I would add 2 more steps so you end up with closer to a 7" rise (or at least 1 so you get to an 8" rise, makes the construction math way easier). In most of the places I've worked (educational, commercial, and non-profit theatres) 8" rise steps are pretty standard, but I'll leave the OSHA and code stuff to Bill and others who know more than me. You didn't mention what sort of production situation you have, so it's unclear what applies to you. Ultimately it's up to you and your insurance company how you decide to apply the code and what your liability is.

From a construction standpoint, with an expectation of 10-12 people on the unit I would build this with 2x4 studwalls- 3 in the center supporting the full depth of the staircase, 2 built at an angle to support the ends of all of the steps, and others as needed to make sure each step is supported every 2' down to the ground(assuming you use 2x12 or doubled up 3/4" ply for the treads). Add a bunch of x-bracing and railings (!) and you should have a solid piece that'll support what you need. Something like the attached drawing could work, provided you make sure you're using appropriate fasteners, metal ties, and be really liberal with that bracing both along the axis of the studwall and along the axis of the steps.

Good luck!


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## TheaterEd (Mar 14, 2017)

kjones9999 said:


> I really appreciate you doing that -- I am so sorry for being so non specific... The base will be 16 feet -- Do you think I could expand the idea?


Lol, Totally read that backwards. That's what I get for multi-tasking. Makes WAY more sense now! I have three rehearsals to sit in on today, so If I have time I'll get on it.


EDIT: I had Time....

I agree that 8.8" steps are too tall, plus I prefer to use pre-fab stringers which if you use 2 x 12 treads will give you an 8" first step and 7" steps after that. With a 12 step staircase like I've mocked up here you will get to 85" so add an extra 2 x 12 to the base and another on top and you're there. Also, I was being lazy so I made the top step 4.5' feet that way the bottom can be 16' and just lose a foot each step instead of 13". What can I say, if a director came to me with those initial specs, this is what I would counter with. If you NEED to a dimension then obviously do what you have to do SAFELY.

I've placed a stringer every 2' in this mock up, I would want to support the other steps with vertical supports and proper bracing, but personally I'm the type to model and build the big parts and figure out the bracing once it's built.

Note, this thing is going to be heavy, but super stable. Working for a high school, I tend to over build things since you never know how they will be abused once built.


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## TheaterEd (Mar 14, 2017)

Just dawned on me, if anyone wants to make edits, here is the sketchup file. Also note, I'm figuring this software out on my own so I am by no means an expert. I just started mocking up my sets like this back in fall of 2015. Before that I was using graph paper and my director had a really hard time picturing what I was talking about. This has really helped us in being on the same page throughout the rehearsal / build process.


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## TheaterEd (Mar 14, 2017)

Can you tell I'm bored in the booth today? So, here are my last two big staircase projects. First we have an angled staircase that was needed for Cinderella. Unfortunately, it was not fully complete until the day of the show and I forgot to get a 'finished product' picture (I actually almost always forget that....) Anyways, here is a picture of it from the final dress. 

This one actually had to roll on and off stage, that was a fun challenge that CB helped me solve actually.

Last year we had another project that involved a 45' wide five step stair case, and two ten step staircases.
Here is a link to the construction video, and below is a picture of the Sketchup model.


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## TheaterEd (Mar 14, 2017)

Jay Ashworth said:


> Just a reminder here:
> 
> (I would) make sure each step is individually supported, not in any way supported by steps further down. An installation contractor screwing that up was the root cause behind the Kansas City Hyatt disaster in the 90s.
> 
> I'm not sure that's applicable here, but some designs might go that way, so I figured I'd point it out.


Not to keep talking to myself, but I was on a humor website when this video popped up with a break-down of the Hyatt disaster. Not particularly relevant to my mock up for this staircase, but I can see how different designs could bring this into play.


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## Jay Ashworth (Mar 14, 2017)

Oddly, my sister just sent me a link to that as well; I haven't watched it yet.


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## kjones9999 (Mar 15, 2017)

TheaterEd said:


> Not to keep talking to myself, but I was on a humor website when this video popped up with a break-down of the Hyatt disaster. Not particularly relevant to my mock up for this staircase, but I can see how different designs could bring this into play.



Thanks everyone especially Ed.

So here's the big question-- I could do stringers and 2x12s, or individual platofrms framed with 2x4s and individually supported... All dimesnions being similar, I am thinking the platform approach will be much cheaper. Does everyone agree?


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## TheaterEd (Mar 16, 2017)

kjones9999 said:


> Thanks everyone especially Ed.
> 
> So here's the big question-- I could do stringers and 2x12s, or individual platofrms framed with 2x4s and individually supported... All dimesnions being similar, I am thinking the platform approach will be much cheaper. Does everyone agree?


The stringers and treads will cost around $380, but that doesn't count the lumber you will use to support the structure. Conversely you could probably do platforms for around $15 for a 2' x 8'. You'll need between 8 and 10 different platforms at which brings you to $150 and then you'll need to build up your steps. So you could be a little more cost effective by going the platform route (especially if you have some in stock). You'll probably end up around $450 with stringers and around $220 with platforms. 

I'm trapped in the booth for a couple of hours again this morning, so if I don't come up with any other project to work on in here, I'll mock up how I picture a platform version.


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## BillConnerFASTC (Mar 16, 2017)

It seems the appearance of the two options is significant and I would think a factor. I have no idea how "finished" these should be but two or three stringers and 2 by or 3 by treads would have to be much faster to build.


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## TheaterEd (Mar 16, 2017)

So here is what you originally asked for. 88" tall, ten steps. In my opinion, the worst part about this plan is the measurements. I needed a lot of decimals to make the steps rise evenly so you will need to be very precise with your measurements when making legs for these. Alternatively, make the top height a slightly different number. Currently each step is 8.8" which is 8 13/16". I work with high school students, in general, they don't do well with 1/16" increments. Additionally, the leg units and support structure are going to take quite a bit of time.


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## Van (Mar 16, 2017)

BillConnerFASTC said:


> Did you forget OSHA? And if it's occupied - by performers or technicians or the public - it is required by law to meet building and fire codes. The person's means of egress at the middle of those stairs is either up or down those stairs and law requires every occupant be provided with a means of egress.


Yeah, About that. The rules, as followed by most theatres producing Plays and Operas should follow OSHA standards Everything backstage, escapes, egress and access should be within "standard" building codes and limits. Onstage as normal all 'normal' standard engineering should be employed, however, Stair Rise and Run, maximum elevation of ramps, surfaces, railings, and fall protection fall into Theatrical/entertainment standards. Equity claims jurisdiction over maximum allowable angle for rakes, ramps and other playing surfaces. When constructing anythingnon standard as a TD I always consulted with the Equity rep on the show and if a deviation from a standard flat surface presented itself as part of the design the equity office in always received copies of the drawings for review. 
All theatres should, enforce standard construction site safety measures during the rehearsal process. If there is an elevated walkway (a mountain path per se) it should have adequate railings throughout the rehearsal process. if the railing is not a scenic element, however, it is to be removed during tech rehearsals and performances. 
The idea, as I have reviewed with several A'sHJ is that in a performance situation the actors and technicians are trained to the conditions they are working in.
As far as the Stage being a "Means of Egress" no, it is not nor should it EVER be considered a Means of Egress. It is a performance space just like an arena floor. there is to be NO unauthorized or qualified or unattended member of the public on the stage or in ANY performance area without proper approval or Accompaniment. 

No, I haven't forgotten about OSHA, and while you "technically" say they have Jurisdiction everywhere, the Local AHJ is the primary arbiter of who has jurisdiction. If Scenic Designers and Technical directors were to follow you interpretation scenery and Stage Design would turn into cubes with soft edges and Handrails everywhere. That does not serve the Art. Acting, Dancing, Performing are more than a factory floor job and to that end they are rehearsed, studied, choreographed.


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## BillConnerFASTC (Mar 16, 2017)

Actors Equity can't "claim jurisdiction over" OSHA for employees in the US. They can have more stringent requirements but they cannot relax or usurp OSHA regulation. AHJ's and building officials are municipal or state employees most often, and are not responsible nor empowered to enforce federal law. With rare exception, no one is out there "enforcing" OSHA - but they can show up as a result of an incident. They certainly did when the panda bear fell into the orchestra pit at the Fox in Atlanta during a Christmas Carol, and OSHA has investigated other stage falls and cited the owner. I ofetn complain that no one at OSHA will say this is OK or that isn't, and that is why I support the codes with a local presence who for the most part are willing to try to work with you.

And every occupant of every part of of every building that is covered by the usual building and fire codes are required by law to have a means of egress. There is no getting around that. Can you talk to and get some variance for what we do? Often yes, but not guaranteed, and rarely expressly stated. Find a building official that disagrees - that it's OK to effectively "lock" someone on a stage and not afford then a way out.

Check here https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=22337 where an OSHA director states it pretty clearly. Yes, is a guard rail or compliant rise and run geometry always required? No - but to say that because it's a stage you don't have to concern yourselves with such things is irresponsible and bull pucky. Even NFPA's Life Safety Code now requires you to protect people at the stage edge form falls where the exception from the requirement for a standard guardrail is used - which is for any fall hazard over 30".


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## kjones9999 (Mar 16, 2017)

TheaterEd said:


> So here is what you originally asked for. 88" tall, ten steps. In my opinion, the worst part about this plan is the measurements. I needed a lot of decimals to make the steps rise evenly so you will need to be very precise with your measurements when making legs for these. Alternatively, make the top height a slightly different number. Currently each step is 8.8" which is 8 13/16". I work with high school students, in general, they don't do well with 1/16" increments. Additionally, the leg units and support structure are going to take quite a bit of time.
> View attachment 14538View attachment 14539View attachment 14540



Thanks Ed! This helps tremendously.


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## kjones9999 (Mar 16, 2017)

BillConnerFASTC said:


> It seems the appearance of the two options is significant and I would think a factor. I have no idea how "finished" these should be but two or three stringers and 2 by or 3 by treads would have to be much faster to build.



Thanks for the response Bill. It only needs to look good from the front, and I plan to cover with luan.


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## BillConnerFASTC (Mar 16, 2017)

kjones9999 said:


> Thanks for the response Bill. It only needs to look good from the front, and I plan to cover with luan.


So just wrapped and flat? No nosings or shadow lines? Just trying to understand.


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## kjones9999 (Mar 16, 2017)

Pretty Much -- Lined with rope light or similar. So basically just flat boxes.


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## Van (Mar 17, 2017)

BillConnerFASTC said:


> Actors Equity can't "claim jurisdiction over" OSHA for employees in the US. They can have more stringent requirements but they cannot relax or usurp OSHA regulation. AHJ's and building officials are municipal or state employees most often, and are not responsible nor empowered to enforce federal law. With rare exception, no one is out there "enforcing" OSHA - but they can show up as a result of an incident. They certainly did when the panda bear fell into the orchestra pit at the Fox in Atlanta during a Christmas Carol, and OSHA has investigated other stage falls and cited the owner. I ofetn complain that no one at OSHA will say this is OK or that isn't, and that is why I support the codes with a local presence who for the most part are willing to try to work with you.
> 
> And every occupant of every part of of every building that is covered by the usual building and fire codes are required by law to have a means of egress. There is no getting around that. Can you talk to and get some variance for what we do? Often yes, but not guaranteed, and rarely expressly stated. Find a building official that disagrees - that it's OK to effectively "lock" someone on a stage and not afford then a way out.
> 
> Check here https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=22337 where an OSHA director states it pretty clearly. Yes, is a guard rail or compliant rise and run geometry always required? No - but to say that because it's a stage you don't have to concern yourselves with such things is irresponsible and bull pucky. Even NFPA's Life Safety Code now requires you to protect people at the stage edge form falls where the exception from the requirement for a standard guardrail is used - which is for any fall hazard over 30".



I'll take my thirty five years of actually doing theatrical productions and working with AHJ's in practical application of codes on the state and national level and bank on it it over your comments of 'Bull Puckey'.

I do not believe ANYONE mentioned locking someone on stage, did they? Was I not Paying attention to the OP? I believe the question was concerning whether or not one could deviate from the 8/12 7/11 "standard" stair rise/run
The simple answer without hyperbolic "Well according to..." is Yes, you may. on Stage. as a scenic element. as long as proper training and safety measures are taking by the actors and people working on stage. it is NOT a public space. 
The stage is NOT a means of Egress for the Audience. It never has been and NO theatre is designed for that as an intention unless we're talking a Blackbox in which case you better make damn sure you provide adequate exit lighting and fire lanes for escape. . Show me a "means of egress within 32'" of a performer on a wire in Ka.

Actors and Technicians are trained for use of the Set. It is a Tool. EVERY backstage area MUST comply with standard Life Safety codes. But please, show me the handrails and "No more than 3/4" rise to a foot" ramp on Ka.


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## BillConnerFASTC (Mar 17, 2017)

Van said:


> I'll take my thirty five years of actually doing theatrical productions and working with AHJ's in practical application of codes on the state and national level and bank on it it over your comments of 'Bull Puckey'.
> 
> I do not believe ANYONE mentioned locking someone on stage, did they? Was I not Paying attention to the OP? I believe the question was concerning whether or not one could deviate from the 8/12 7/11 "standard" stair rise/run
> The simple answer without hyperbolic "Well according to..." is Yes, you may. on Stage. as a scenic element. as long as proper training and safety measures are taking by the actors and people working on stage. it is NOT a public space.
> ...



Any or all parts of the stage are a means of egress for the occupants on the stage. All occupants - audience or actors or technicians or the janitor - must be provided with a means of egress. It's a basic tenet of the building and fire codes, and of OSHA requirements.

I can cite laws that say yes you do have to provide all occupants on stage with a means of egress - an unobstructed way out of the building to the public way. Can you show me where this is contravened by law, or have you just gotten away with it, as many people have?

OSHA does permit alternate means of protection. I believe, for instance, KA has a written plan for getting people out, where each part and action has been considered. They did not just conceive of the act and do it without a plan in place for each case where the normal prescriptive devices - guards, stair geometry, marking, etc. weren't possible. We should encourage the same thought for a high school, college, or community theatre event - to think about and have a plan for safety for everybody in place BEFORE the incident occurs. I reject what seems like an attitude to just ignore safety because it's a stage or art, and that a handrail or normal rise is not possible so do nothing to protect those people from fall hazards. It does seem to be what you are advocating for and claim to have done a lot.

If the OP wants to build a stair with 8.8" risers that's fine - but think about how to protect the people that are using it from the known hazard, just as routinely as one wears a hard hat, high visibility vest, steel soled shoes, and eye protection on a construction site. Those requirements are a result of study and thought and more and do prevent injuries from the normal hazards of construction.


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## kjones9999 (May 28, 2017)

I wanted to follow up on this.... I appreciate all of the advice....
I ended up going with individual platforms 1 foot deep, with legs. I went with a 7.25 " rise and they worked flawlessly. This is the first set of stairs I have built not using a stringer, and these things were rock solid once fastened together. I will use this method from here on out.

Here is a pic just after strike and another production photo.

https://drive.google.com/open?id=0B52H4oP6S5zlTDFDYWIwTXo0ckU

https://goo.gl/photos/kxJLgPSjYvC7YUGQ9


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## Jay Ashworth (May 29, 2017)

Jay Ashworth said:


> Just a reminder here:
> 
> (I would) make sure each step is individually supported, not in any way supported by steps further down. An installation contractor screwing that up was the root cause behind the Kansas City Hyatt disaster in the 90s.
> 
> I'm not sure that's applicable here, but some designs might go that way, so I figured I'd point it out.



Funniest thing:

I'm mostly a booth guy, but I got to help set up some Wenger for the Fringe festival one of my houses recently hosted, and they do exactly the thing I was warning about: the legs of the taller platforms, used for audience seating, *sit on top of* the platforms of lower ones; so each leg carries some of its own platform's load, and some of that above/behind it. And I hadn't known that then.


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## RonHebbard (May 29, 2017)

Jay Ashworth said:


> Funniest thing:
> 
> I'm mostly a booth guy, but I got to help set up some Wenger for the Fringe festival one of my houses recently hosted, and they do exactly the thing I was warning about: the legs of the taller platforms, used for audience seating, *sit on top of* the platforms of lower ones; so each leg carries some of its own platform's load, and some of that above/behind it. And I hadn't known that then.




Jay Ashworth said:


> Funniest thing:
> 
> I'm mostly a booth guy, but I got to help set up some Wenger for the Fringe festival one of my houses recently hosted, and they do exactly the thing I was warning about: the legs of the taller platforms, used for audience seating, *sit on top of* the platforms of lower ones; so each leg carries some of its own platform's load, and some of that above/behind it. And I hadn't known that then.




Jay Ashworth said:


> Funniest thing:
> 
> I'm mostly a booth guy, but I got to help set up some Wenger for the Fringe festival one of my houses recently hosted, and they do exactly the thing I was warning about: the legs of the taller platforms, used for audience seating, *sit on top of* the platforms of lower ones; so each leg carries some of its own platform's load, and some of that above/behind it. And I hadn't known that then.


Looking back to your mentioning of the Hyatt disaster reminds me of Tim's quote on ProSound where he referred to it as "Bridge over troubled WAITERS". As bad and sad a situation as it was, Tim's blackly twisted reference still makes me giggle when I recall it. Foregive me, I MUST be one sick puppy.
Toodleoo!
Ron Hebbard.


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