Cold-Fromed Steel Stud Slip Track

[BSVBD]

Should the general contractor be asking us whether they should be using deflection slip track for the steel studs that go up to bottom of roof deck?

The contractor IS quite competent and also over 50% of our income for the past 3 decades; therefore, we often do appease their desires, requests, questions and so on...

I DID provide the total potential live/snow load as 1.8" for the center of 54' span for the OWS Joists.

I avoided giving a definite answer, rather, along with providing the potential deflection, i recommended slip track throughout, at all walls, not just those nearest the center.

Is it our responsibility to specify such components, being aware of the potential need? I think "Yes".

Opinions? Suggestions?

Thank you!

 

[jayrod12]

Of course they should if the steel studs are non-load bearing.

 

[sponton]

can't the joist manufacturer camber the joist so deflection won't be a problem? We don't specify them but we do limit our total deflection to 1/2"

 

[DETstru]

As far as I've seen, use of deflection tracks on all non-load bearing metal stud walls is standard practice for partition wall framing. I typically see this on an architectural sheet (e.g. Gypsum Board Partition Types).

 

[XR250]

I would specify it. If the wall is tall, make sure you check the track leg for bending and the connection to the roof deck for moment.

 

[jike]

Deflection tracks are standard for non-load bearing interior walls. Thickness and depth may vary depending on lateral load to be resisted. For large lateral loads (such as on exterior non-load bearing walls), sometimes deflection tracks may not work and slotted clip angles may be required.

Whoever the CFS designer is, he should specify the size, thickness and depth of deflection tracks or adequate slotted clip angles. Do you have a CFS spec which calls for the GC to hire a qualified designer?

 

[wannabeSE]

BSVBD,
I am not sure exactly what you are asking. Are you asking if the construction documents should specify a particular deflection track or head of wall assembly? Or, are you asking if the contract documents should specify the amount of deflection the head of wall assembly needs to accommodate?

At a minimum, the amount of deflection expected should be specified. Beyond that, it depends on contract and specification. On some jobs (OSHPD), we provide a complete set of details for the partitions including the head of wall on the structural drawings. Often times, some typical details are on the architectural drawings with the head of wall deflection specified. Sometimes (more for exterior cladding) an L/xxx not to exceed x" deflection requirements is included in the specification rather than being detailed on the drawings (more common with our exterior cladding and exterior framing specs than in the non-bearing framing spec). If you want to push it off to the contractor, I guess you could clearly note on the construction documents that the bar joist deflection (deferred submittal) needs to be coordinated with the head of wall assembly; but whose going to check to make sure the contractor does it.

1.8" is bigger than most architects and contractors like. A slotted track might be hard to find, so another type of head of wall detail may be needed. Finding an assembly for a rated wall can be even more challenging. Often times, we stiffen the framing to limit the live and snow load deflection to 3/4". But, I've still had architects complain about +/- 3/4"(1 1/2" total).

PS cambering doesn't help with live load or snow load deflection at the head of wall.

 

[Ron]

If you are doing delegated engineering work for the contractor, you should specify the track you expect. Don't wait for the contractor to ask the question. Slotted track should certainly be used if you anticipate deflection.

 

[MrHershey]

Assuming you're the building EOR this sounds like they're either winging it on the CFS or they weren't required to get it engineered and are assuming you (or probably more accurately the architect) are showing everything that needs to be provided. Which is usually a bad assumption if the architect is the one showing the CFS.

Short answer is probably. Long answer is they need to ask whoever designed the CFS. If that's a specialty designer like Clark Dietrich then ask them, though they're usually good about showing everything they need to begin with. If it's the architect, then ask them (and they'll probably turn right back around and ask you). If it's you, then you need to tell them what you want.