There are few ways of hiding cables for a TV wall mounted over fireplace.
Concealing wires in the wall over fireplace is far different than In-Wall Vertical wire concealment. Hiding cables in the wall over fireplace can be a tough task even for someone who considers himself to be a handy person. It requires careful planning, precise measurements & certain tools that average Joe wouldn’t normally have sitting around in the garage. Tackling a project like this can also be time consuming so you need to dedicate at least few hours of your time to make sure things are done properly the first time.
First of all, you need to know whether or not the wires can be fished through the wall by knowing the structure of your fireplace and surrounding wall.
Usually, in a newer house or a town home (1980’s and newer), your wall should be drywall and wooden studs around the Gas Fireplace. In this case, you can fish wires though the wall.
If you got a Wood burning fireplace which is usually found in older homes, then the wall is most likely built with bricks around the fireplace so you won’t be able to fish the wires through the wall. In this case, consider hiding wires with wire raceway instead.
If you live in a newer house or townhouse and plan to mount your TV over gas fireplace on the main floor and if your basement is unfinished, then wires can be fished from the wall above the fireplace, down to the basement and then fish the wires back up to the main floor through a wall and come out where your components are going to be placed.
If your basement is finished then fishing wires horizontally across the wall will require cutting drywall to drill through every single stud to feed wires through the studs horizontally across the wall and then fish cables vertically down to somewhere near the baseboard where your components will be placed.
Take a look at raw examples below. This installation required 25ft cables to run cables from above the fireplace, down through the unfinished basement and then back up to the adjacent wall where custom wall plate was installed for 4 x HDMI cables, Toslink Optical cable & Cat5e Ethernet cable.
Here’s another example where the wires were concealed in the wall over fireplace and through the unfinished basement. This installation required hiding cable box inside the cabinet behind closed doors next to the fireplace, so an IR repeater was installed to control the box out of sight.
In the picture below, notice that there’s an existing electrical outlet for components & coax jack for the cable box inside the cabinet.
More examples of in-wall wire concealment for TV above fireplace.