Existing Z roof gurts

[kaisersoze]

I am looking at a project where Z girts, spanning 25', spaced 5' apart were used on a storage building. They want to some new RTUs on the existing structure.

While doing other field measurements I also did a quick check of the Z girt (3"x8"x3") but I am not sure if I got the thickness right. I came up with 0.15" thick which seems high. I have noticed that some Zs have a tiny lip at the end which may end up with an inaccurate thickness using VernierCaliper so I may go back and use a metal gauge.

But my question is, Is there a source where I can look up similar girt's member properties to see what gage and grade may have been used. The building is from the late 80s.

Kaiser

 

[kaisersoze]

Its a Sunday, so apologies for all the typos including GURTS....

Kaiser

 

[slickdeals]

You may want to look at Nucor Building's website or contact your local Butler building rep (

http://www.butlermfg.com/).

 

[MiketheEngineer]

Good luck!! Most of the sections are proprietary.

As has been discussed numerous times in the forums - these buildings are designed with little or no reserve. I am am actually afraid to walk on some of them.


Even a 200 lb RTU might be impossible. Try as you might and I wish you good luck.

 

[BAretired]

The CISC Handbook of Steel Construction lists properties of cold-formed Z-Sections, Uncoated. The maximum thickness listed is 3.43mm (0.135") but as stated in an earlier post, they could have been proprietary, so there is no guarantee that this source would be accurate.

BA

 

[JedClampett]

Your best bet is to add more girts just to support the equipment. But as the posters above mention, these buildings are designed to the gnat's buttocks, so it might affect the frame. Then the additional wind loads could overload the lateral load carrying system.
I think you're right though. I've never seen Z girts that thick. Double check your measurements.

 

[ajk1]

If you get a caliper that is in the configuration of a "C", you can get them over the little lip that you describe and measure the metal thickness wihout interference from the lip. I bought digital calipers like this at a science store for $180 Canadian, specifically for this situation.

 

[MikeHalloran]

If you can accurately measure all the section dimensions, you can plug it into CUFSM software and have some fun with it.



Mike Halloran
Pembroke Pines, FL, USA