Metal stud attachment

[eatapeach]

The contractor has installed metal stud tracking to 22 ga. roof decking. When question about his attachment of the studs to the track he stated he will not attach and allow them to float with a 1/2 gap for deflection. I know ASTM allows the metal stud not to be attached to the top track however that raises the question of walls attached to structure or lateral support . How is the wall supported by structure if not attached to the track? Another concern is because the decking is 22ga. it is not considered structural so even if attached a argument could be raised that its still not attached to the structure. My past experience many engineers state not to attach to the deck however that is not stated on these drawings. In this case the contractor attach the track to the bar joist which would be to the structure.
Thanks

 

[wannabeSE]

When the studs are not attached to the top track, bridging or blocking is typically installed near the top of the studs. The top track can move side-to-side (in-plane) and up-and-down without having the partition fall over. See page 29 of SSMAs details at

http://www.ssma.com/filebin/pdf/SSMA_Details.pdf.

The SSMA also has a technical note for calculating the lateral capacity of this arrangement at

http://www.ssma.com/filebin/pdf/tn01.pdf

22 GA is thin. But, I don't understand you concern or the assumption that it is non-structural.

 

[eatapeach]

Thanks for the info.
22 gauge metal is not considered structural. There is a 20 gauge that is structural however typically its 18 or lower.

 

[msquared48]

First I ever heard that 22 gage material is not structural.

I guess I will have to go back and redo a few projects here, especially where metal decking was used.

Mike McCann
MMC Engineering

 

[eatapeach]

The structural engineer I worked for did not consider 22 gauge decking as a structural component. This could have been due to the fact he knew subcontractors would be supporting from it and he took these loads into account not sure why. He never considered using anything less than 18ga. for roof decks. Then again these were 500,000 sq.ft. high schools that we design for. I'm not use to seeing such a light gauge deck used on commercial roofs.

Thanks

 

[SlimSE]

WannabeSE has described what methods I use for this type of application. 22gauage deck not being considered a structural component is news to me. I have used 22 gauge deck as a roof deck/diaphragm many times.