Splicing metal studs interior partition wall

[mfstructural]

I have a client (a contractor) that has built an interior partition wall in a warehouse. They had some 20' laying around and used them to construct a 24' tall wall (height to underside of decking is 24'). Of course 20' is short of 24' and so they spliced a 4' piece to the 20' to get the full height. The spliced with an 18 gauge track. Not sure of screw configuration. He claims they put a slip track in at the top but it doesn't seem like it from the picture. Eventually I will go out and verify this. Anyways, the building inspector wants to cover himself and wants an SE to seal a calculation and drawing specifying the spliced connection. I spoke to the contractor today asking him some questions regarding the slip track and connection. He says that they are going to remove the current screws and splice track and re-install as the sealed drawings specify. I asked him if there was a slip track. He said "don't worry about the slip track we don't need to show it on the drawings"...yea right. I told him I have to include it otherwise axial load may be inmparted on the wall due to roof deflection. Has anyone ever come across splicing of studs like this? The interior loads are pretty low at 5psf and the splice is near the end, but I'm just curious if anyone has done this before.

 

[msquared48]

Show the slip detail and show diagonal kickers from the splice to structure above at 4 to 8 feet or so along the wall. That's normal for a splice condition like this.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[ron9876]

Yes I have. I spliced with a long piece of track. Have to analyze the various parts. I would guess that 4' from the support and since it is an interior wall should work fairly easily. But will need the slip track.

 

[mfstructural]

Thanks for the responses..
ron: did you also use a brace like msquared suggested or did you check the moment transfer through the track and screws (which is minimal 4' from the support).

 

[ron9876]

No. Don't think you would need both. Maybe give the contractor two options.

 

[mfstructural]

Based on the calculation the tension/compression to be transferred over the splice is about 800 lbs. How many screws is typical for this type of connection? I would think at least 6 on each side of the splice even though less are required.

 

[beemer218]

I have done this splice detail often. You don't need the kickers. The splice is near the end of the member so moment is low. You DO NEED a slip track at the top of the wall so you don't get axial load on the interior wall studs. For 18ga studs a #10-16 screw has an allowable shear of 265lbs. You can get this data from SSMA catalog. A free download from steel stud manufacturers association.

 

[mfstructural]

That's what I did. Just decoupled the moment at 4' from the end and used a #10 screw. Ended up needing 4 screws on each side along each edge of the member so 8 screws total. And I also did specify a slip track to avoid axial loading.

 

[beemer218]

MF you did good. That's exactly the way to do it (imho). No problemo.

 

[mfstructural]

What screw spacing do you typical use? I'm specifying 2" typical.

 

[mfstructural]

Along the length of the member.

 

[beemer218]

Yes, 2" is good. AISI min. spacing is spec'd at 3 x diameter, but 2" is good for this application.

 

[mfstructural]

Yes, I checked AISI and also saw 3d for spacing and 1.5d for edge. I'm 1" from the edge (4" transverse spacing) so I'm ok there too.