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Author Topic: a roof system question  (Read 4322 times)

Bryan Roberts

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a roof system question
« on: August 22, 2004, 03:48:56 pm »

I am doing a travelling festival this fall and have gotten some serious conflicting reports about doing a roof. Last year was a ballast system with 4 crank towers to control the roof. The only problem was it took 3 hours to set up and tear down everything (sound and lights too). Then I did an outdoor show where we used 4 genie stands and put a roof tent over it. We closed the truck door after 1.5 hours.

Although the time save is great, I want to make sure this is not dangerous. Now I understand wind can be a SOB but I would lower the ballast system too if wind hit 40 mph.

SO!! The question is: am i playing with fire if I use the more appealling time saving option of the genie stands with tent roof (no ballasts).

Set up is a 30 x 24 stage with a 30 x 20 roof

Thanks friends!!

bryan
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Bryan Roberts
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Bob Cap

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Re: a roof system question
« Reply #1 on: August 23, 2004, 11:32:04 am »

Bryan,

I have been setting up roofs for many years and am amazed at the number of roof system I see on the net set on Geini Lifts. How do you anchor the roof down?

We used to use scaffolding towers and now use self errecting towers that are guy wired down.

I believe a roof sitting on Geini Lifts would blow away long befor the wind speed hits 40mph!

To be able to pack a roof, sound and lighting in 3.5 hours is a quick load out for me. Read impossible. (Maybe my system is a little larger than yours)?

Take the extra time and keep safty in mind.

Good Luck

Bob Cap
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Bryan Roberts

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Re: a roof system question
« Reply #2 on: August 23, 2004, 04:13:33 pm »

ours is a small set up (30 x 24). the time is what is killing me. I am  curious. Since we have all seen the genie stand roof special, has anyone had experience with this falling over. Or has anyone found and easy to secure it? I was thinking spansets at the top of the genies (3 per side) and then use those ratchet wire thingys (that's professional terminology) to secure each tower down to ground.

Still wondering.

Thanks folks!!

bryan
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Bryan Roberts
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Mac Kerr

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Re: a roof system question
« Reply #3 on: August 23, 2004, 04:13:45 pm »

 Laughing My first reaction to the roof on Genie's with a 40mph wind was that you wouldn't have to lower it, you would be chasing it across the parking lot.

Mac
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Alan Hamilton

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Re: a roof system question
« Reply #4 on: August 23, 2004, 05:16:44 pm »

tallboypro wrote on Sun, 22 August 2004 20:48

I am doing a travelling festival this fall and have gotten some serious conflicting reports about doing a roof. Last year was a ballast system with 4 crank towers to control the roof. The only problem was it took 3 hours to set up and tear down everything (sound and lights too). Then I did an outdoor show where we used 4 genie stands and put a roof tent over it. We closed the truck door after 1.5 hours.


bryan


There are different ways to approach using the genies, and spansets and guy cables can figure into the equation. You want you system guyed no matter how you are doing it.

I'm curious how the genie system is so much faster? That makes me wonder about the other parts of the setup which might concern me more than the use of Genies.

1.5hrs seems too fast to me for any roof system... except an EZUp tent of course Wink



-AlanH
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Bob Cap

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Re: a roof system question
« Reply #5 on: August 23, 2004, 06:49:40 pm »

Bryan,

I'm sorry you seem to think saving a couple of hours is important in this life time.

Let me explaine some of the forces at work here.

When you raise your roof with Geini Lifts you have the first force, gravity, pulling down on the weight. When you get your roof up to your working height you have to make sure it dosen't fly away from the lift of the air moving around it. Hence you would guy wire it down to the ground with two cables at each corner. Now you need to consider how tight you are going to guy these. This adds the force downward of the guy wires.

Since a Geini is only rated at 650 or 800 pounds of lift you will probably over load the lift causing the cables, sheves or shafts to break or collapse.

Now you MIGHT get lucky. Have a really light load. No wind. Easy set-up and load out.

OR.....

You might kill someone!

In reality the guy setting up the real roof, taking all that valuable time probably want to charge you more than the guy with the Geini system......

I hope no one dies from you saving money....

Bob Cap
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Bryan Roberts

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Re: a roof system question
« Reply #6 on: August 23, 2004, 10:35:07 pm »

it's actually got nothing to do with saving money. It is about logistically being able to do the tour. If it takes 3.5 hours to get out a show that drops at 10:30 that means we say good bye at 2 am. If it is more then 6 hours to the next show (and this is a Christian tour so that is happening alot), then we are screwed trying to make an 8 am load in, thus having the 3+ needed hours to get this thing up and started in time. The crew last year killed itself doing it this way and the tour suffered with it.

Now, I am not discounting your wisdom, but so far no one has voiced an experience of this actually turning ugly. Just the possibility of ugly.

On the other hand, I have seen many companies do it the geni lift way and never have a problem.

Are those wire ratchet things called pulleys or what. I know what the spanset is. And the two wires off each tower sounds like the way to secure it.

bryan
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Bryan Roberts
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Bryan Roberts

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Re: a roof system question
« Reply #7 on: August 23, 2004, 10:57:41 pm »

Hey guys
Thanks for the input. I just got off the phone with my boss and told him I will not endorse using the geni stand option on this tour. You are right, safety is no substitute for time saving or money savings.


Thanks again!!

bryan
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Bryan Roberts
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kevin kuptz

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Re: a roof system question
« Reply #8 on: August 25, 2004, 10:33:27 pm »

I recently had to give a deposition for a case where I had provided the stage but another contractor provided the roof - We were both "subcontractors" to the bigger company who had the contract, but was overbooked and couldn't provide the gear. The roof company was too busy to bother with guy wires, even though the roof would be raised to over 25 feet for the show in a n open field between two forests that acted like a wind tunnel. Luckily when the roof came off (and We knew it would) it was at night when it was lowered and it only traveled about 45 feet into the parking lot behind the stage, damaging 6 vehicles parked there. We were lucky that the roof sheared the truss off when it twisted loose and didn't actually hit any of our stuff!
I take all of this seriously, but didn't realize when we left the initial setup that roof supplier wasn't going to tie the roof down! If you think Genie's are OK outside -think about this. This roof was 5 feet above the stage floor in it's "resting" position. What would have happened four hours earlier when there were 5,000 people in front of it and it was higher up in the "wind band"? Never short safety for speed, even if it "seems okay". There is too much at stake - this roofing company, the main contractor and the festival are all now being sued for damages, but things could have been far worse had there been injuries or deaths involved here! I was deposed as a witness, but could have been named in the suit also!






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Brian Ship

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Re: a roof system question
« Reply #9 on: August 25, 2004, 11:37:39 pm »

It's been a lot of years since I have done a tent set up, but it would seem to me that as long as the Geni is not supporting the tent roof that it as a piece of equipment, much a seperate piece of equipment givent the roof is self supporting has little to do with the tent roof if if blows or not away.  Big long stakes drilled into pavement and large ratchet straps, two per post the main detail.

In any case given a misunderstanding on my part that the lighting rig is seperate from the tent roof in general, the GENI lift system of hanging the truss should with legs be sufficient to prevent problems in the wind for a standard rig with or without tent over it.  Granted for a large storm I would tend to lower it, but I just can't see some Geni tower ending up in the parking lot.  

If in question, in the past, I have found that if arranged for, the tent guys are very reasonable in drilling and staking a few holes than tying your tower also down in it's own system of support.

While I have not done such a thing, I expect such a seperate derrived system of roof and truss, much less support for each individually would be sufficient for a storm, much less allow the truss to come down as desired fast without worrying about wet tech people even while doing so.  Asleep on the bus on route while the tent guys worry about the tent roof in the parking lot or what ever the next day.

5 years in doing special events for Chicago - granted as a Carpenter, never saw a tent just blow away.  Could happen but I expect the lighting when seperate has seperate worries than the tent and you no longer have to worry about the ballas6t of a tower in counteracting the wind.

Just a thought.
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