Concrete – How to attach a TV mount to a resilient channel wall

concrete-blockmountingsound-deadening

first SE post!

MY QUESTION: 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 the miracle of the StackExchange Home Improvement answer to someone else's question, 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 (reposting here to save you all a browse):
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.

Best Answer

Your best option is to cut a peice of 1/2 " finish plywood around 36 inches wide and tall enough to split 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. enter image description here This method will allow you to support several hundred pounds, assuming you 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.