Strange office wall construction - modular?

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LarryFine

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
I am to mount a TV in a partition wall in an office building. This is a wall that goes from floor to suspended ceiling, obviously added after construction, as the wall butts the ceiling. What's weird is that the wall is only about 2" thick, feels like it's made of drywall on wood framing,, and has what appears to be a white-painted top surface (the edge that butts the ceiling) between a pair of L-shaped trims that cover the edges of the drywall.

My question is for anyone familiar with this kind of wall. Is there regularly-spaced framing inside, or am I better off drilling all the way through the wall and using bolts with nuts and fender washers, or even flat stock drilled to match the bolt layout, for better holding strength? The backside of the wall is a storage room, so hardware on the back of the wall won't be an issue. I can decide on which side of the wall to place the bolt heads then.
 
For giggles I would drill a mounting hole through one side first then probe around to see what's in there. Check the thickness of the sheetrock to see if it could hold the anchors. Might be filled with foam too.

You know you are going to drill all the way through and use fender washers on the store room side. ;)

-Hal
 
Assuming we are talking about a larger TV, a TV mount should be attached to 2x4 wood framing. If the wall is made with 2x4 wood studs on the flats, that would be fine to support the mount. If it's 2x2 wood or worse yet, metal studs, I would suggest installing a 5/8" plywood backer board on the closet side of the wall screwed in at least four places into the studs. Then attach the TV mount through the wall, a stud, and the backer with sturdy bolts.
 
They mounted a large display in the main lobby. Backside of the wall is in the computer room. There's now a 2' x 4' panel of 3/4" or 1" plywood on the computer room side of the wall, and hardware sticking through from the monitor mounts in the lobby.

I don't think they asked IT for permission...
 
LarryFine said:
What's weird is that the wall is only about 2" thick, feels like it's made of drywall on wood framing,, and has what appears to be a white-painted top surface (the edge that butts the ceiling) between a pair of L-shaped trims that cover the edges of the drywall.
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Not suggesting it's what you have, but I've seen such walls with a 2x4 turned sideways, and once, with 2x2 lumber used. They were, in all 3 situations, not load bearing so structural building codes didn't apply. I did not see electrical details. I think mobile home devices would fit? Listed ... ???
 
I expect to use MC since the receptacle cable will extend into the ceiling space, which means I'll want a metal box. I usually use an angle connector in a rear KO, but I'll be too shallow here. I plan on cutting the box hole first and measuring the interior wall depth.

I might find a metal box with a KO in the side, or I might put in a 4" sq. box with an old-work-box adapter and install a quad. If there was a receptacle in the wall, I'd just use NM and one of these:

carlon-boxes-brackets-b117rswr-64_400_compressed.jpg



I could offer to add a receptacle on the other side of the wall and mount two boxes back-to-back. I could even use EMT or Wiremold and not have to drill and fish the cable. A data cable has already been fished in, so I know the wall is hollow.
 
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GeorgeB said:
Not suggesting it's what you have, but I've seen such walls with a 2x4 turned sideways, and once, with 2x2 lumber used. They were, in all 3 situations, not load bearing so structural building codes didn't apply. I did not see electrical details. I think mobile home devices would fit? Listed ... ???
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These appear to be pre-fab walls, but they could be built-in-place.
 
Could they have built the walls with the 2X4's being flat? Locally there is a subdivision of prefab homes built in the 70's that the partitions were constructed that way, all the boxes are 4 square, with all the wall plates being 2 gang, 1 side blank, other is a toggle switch, or duplex receptacle + wired w/ AL too. The flat 2X4 walls can be found old homes too.
 
Seen some walls that were built in mid to late 60's that are non bearing walls, 2" thick, and composed of four layers of drywall - no other framing members. You are not fishing anything into those walls. You are not putting your fist through them either.
 
I would check with the manufacturer of the cubicles. They DO make pre-fabbed walls in modular offices. The only place for cables/power is at the seams where 1 piece joins the other. As for how they are constructed, it should be mild steel studs but don't quote me on that. And How big is the tv?
 
No, these are nothing like pre-fabbed cubicle walls. They look and feel like standard drywall on wood stud walls, except for the thickness. They even have real office-quality doors, and there are wires fished in.

Where I saw a data wire that had been added in the past, I noticed that the hole in the top edge of the wall, butting the suspended ceiling, had what appeared to be a thin, white-painted strip of metal covering what is basically the wall's top plate.

The metal was punctured when the hole through the top plate was made, and is the only thing that made me think that this might be anything other than a typically-constructed wall with the studs on the flat.
 
The TV will probably be in the 50-to-60" range, and the mount is a tilt-only, so there won't be a great bending moment.

I will make the receptacle hole first, and inspect the interior space before deciding. I may just use standard lag bolts into the studs, or go through the wall and maybe use flat or angle stock as backers for the nuts.
 
LarryFine said:
No, these are nothing like pre-fabbed cubicle walls. They look and feel like standard drywall on wood stud walls, except for the thickness. They even have real office-quality doors, and there are wires fished in.

Where I saw a data wire that had been added in the past, I noticed that the hole in the top edge of the wall, butting the suspended ceiling, had what appeared to be a thin, white-painted strip of metal covering what is basically the wall's top plate.

The metal was punctured when the hole through the top plate was made, and is the only thing that made me think that this might be anything other than a typically-constructed wall with the studs on the flat.
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Yeah I know what you mean. I've got an office building that is free spanning trussed with all of the walls built out of what sounds like the same/similar thing you have. At first it looks like regular stick built walls. Has heavy wood doors and door frames and everything. Unfortunately I only installed a new panel in a newly built wall, so I don't know the exact construction of these.
 
There is no space above the acoustic ceiling. That’s where I usually make my hole to see what I’m dealing with. If not the receptacle hole makes sense.


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Maybe run a stud finder over it or possibly an inspection camera. Maybe hit a pawn shop to see if they have any for cheap! Just a thought and Good luck!
 
LarryFine said:
What's weird is that the wall is only about 2" thick, feels like it's made of drywall on wood framing,, and has what appears to be a white-painted top surface (the edge that butts the ceiling) between a pair of L-shaped trims that cover the edges of the drywall.
Click to expand...
It could be a type of C- or U channel that contractors use sometimes, they slide it over the edge to give a crisp edge to the drywall so they don't have to joint compound up against the drop ceiling and the drywall.
In regards to mounting the TV bracket you may be able to use 1/4"-20 T nuts through the studs but the opposite side of the wall would need to be touched up afterwards. That should hold it as long as the wall doesn't fall over ;)
 
I have a snake cam, but for this kind of probing, I just use my folding rule or a flashlight and pocket mirror.
 
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