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How do I safely attach an articulating mount (tilt/pan) for a 75" LCD TV to a "sound deadening" wall that uses resilient channels?

Thanks to this answer, I learned that the bizarre insides of my wall are so-called "sound deadening:" drywall, attached to horizontal metal 'resilient channels,' attached to wood studs, attached to concrete cinder block.

Here's the inside of my wall (this is from 8 years ago when our water heater popped and drained down into the wall).

sound-deadening-wall

I had never heard of such a thing and was image-googling "horizontal studs" when I found the pic that Ecnerwal shared in the linked post:

Ecnerwals-pic

Except I don't think my building includes all the fancy layers, it's just drywall. :/

So what should be my approach?

  • Anchor the mount to the wood studs, through the metal channels?
  • Anchor to the wood studs, avoiding the metal channels?
  • Anchor directly to the metal channels, avoiding the wood studs? (seems risky)
  • Forget both the studs and channels, just mount a plywood backing plate to the drywall with 18 drywall anchors and attach the TV mount to that?

I really don't want to have to open up the drywall in the living room if I don't have to. Not finding any info about how to deal with resilient channel walls. Would love your thoughts.

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    I like your first option the best. I see no reason to try to avoid the metal channels (unless they are really thick and hard to drill thru?). Your last two possibilities both seem risky to me.
    – peinal
    Oct 26, 2019 at 1:50
  • Thanks @peinal - I'm thinking that a combo of that option WITH a plywood backing plate might be the way to go. Plywood at least a yard wide and tall enough to generously overlap 2 of the metal channels. Attach the ply to the wood studs thru the metal channels with very long wood screws (being careful not to squash the metal channels). Paint the wall and plywood and then attach the mount to the plywood. Thoughts?
    – IWantMyMTV
    Jul 29, 2020 at 23:33
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    That seems like a sound plan to me. I would use 3/4" plywood....and perhaps fender washers on the woodscrews to prevent pull-thru.
    – peinal
    Aug 3, 2020 at 1:34

2 Answers 2

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Your best option is to cut a piece of 1/2" finish plywood around 36 inches wide and tall enough to lap over the resilient channel at the top and bottom. That way the drywall will be supported by the channel as will the plywood. Carefully cut the drywall to the same size and firmly secure the ply through the channel into the wood without crushing the channel. You can fill the seam and sand it but choose a filler that remains flexible because wood and gypsum expand and contract with heat and moisture at different rates. Now if you so choose, you can prime and paint.

This method will allow you to support several hundred pounds, assuming your wall can. My TV is a 100lb 70" with a 30" long mount which allows me to turn the TV beyond 90 degrees. In my application I added plywood behind the drywall and replaced the drywall. As you can see from the image I didn't fill sand android paint but that's an optional step.

enter image description here

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    "tall enough to split the resilient channel", I cant figure out what "split" means here? Exactly what do you mean? Apr 16, 2020 at 19:56
  • @Joe Fela, I'm also scratching my head at "split the resilient channel." Do you mean... A) The ply needs to overlap at least 1-2 of the metal channels? If so, how many? B) The top and bottom edges of the ply must align with the center of each channel? C) The ply must be at least half the wall height? D) Other?
    – IWantMyMTV
    Jul 29, 2020 at 23:29
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    I figured out what is meant by the response. He says "That way the drywall will be supported by the channel as will the plywood.", which means that in between the studs, you attempt to insert your panel at exactly half the width of the top and bottom channels. This allows whatever screws are in the drywall and channel to stay while allowing you to add screws through the plywood and channel. My issue with that is that I cannot see how the channels can hold against the torsion of the TV on an arm stand, although his does. And a long stand at that (something like 80lbs at 30", so 2400 in lbs?).
    – Kim
    Jul 9, 2021 at 20:20
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    Part 2: Anyway, I would consider it risky to use Togglers through resilient, but I suppose it should work. I am searching for a solution as well, as I have wood studs but do not want to short circuit the resilient channel. sigh
    – Kim
    Jul 9, 2021 at 20:20
  • Yes I did ... a very inconvenient one :-). I got a stand that does not extend at all and is thus an absolute bear to use. But it solves the torsion problem since there really isn't much at all. I used a lot of heavy duty togglers and it has not budged in almost a year. I am tempted though to simply violate the resilient channel and layer a piece of plywood under a better stand with the plywood lag bolted into the studs directly. Just for the convenience of allowing the TV to swing out properly, which makes it a joy to use ...
    – Kim
    May 30, 2022 at 15:45
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Get yourself some spacers. They're basically little segments of thick walled pipe. Use a spade bit to open a hole in the drywall so the spacers can bear directly against the studs. You could alternatively use a stack of washers, but you'll have to outsmart the wall monster who will eagerly eat the washers if you're not careful.

Widening the gap between wall and TV mount will amp up the demand on your fasteners a bit, so consider upgrading to longer and/or larger diameters to make up for the difference.

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  • Attaching directly to the studs will defeat the acoustic benefits of the resilient channels. To maintain the acoustic benefits, the attachment should be to the resilient channels with proper acoustic attachments, not to the studs.
    – mdfst13
    Feb 10 at 13:23
  • @mdfst13, sure. Maintaining the acoustics isn't a priority to the OP, though. If acoustics are a priority, then attaching a TV to the wall in any way is a bad idea (unless you've got external speakers that aren't attached to any walls).
    – popham
    Feb 10 at 15:55

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