fireplace
I've taking an extra layer of bricks from the front of my fireplace. I want to replace the fronting with marble. The original surface is really rough. My question is should I apply a mortar to smooth out existing front and then put the marble on that, or should I just apply concrete board then put the marble on that?
This is a working fireplace that's approximately 80 years old.
1) you could use wiremold. They make 90ยบ inside corners. I don't like it but if you have use it then it works. Better off to chop a new box in the wall exactly where you want it.
2) There are several ways to put power wiring behind the planks. EMT, ENT, wiremold...there are others less often used. You will need an extension box on the left power box to run out of.
3) The bricks around should just be a facade but why make it hard on yourself? Just bring the TV mount area out far enough to have the media box behind it.
4) Putting power in the back of the firebox will probably be a major pain. I believe that is firebrick surrounded by other brick. You may need to get a bricklayer in on this. Or at least you should study the construction of fireplaces.
I see other problems here, though. The National Electrical Code requires that no point along the floor line be more than 6' from a receptacle. If you cover the receptacles on left and right will there be other receptacles on the wall line close enough to satisfy that requirement? If not you will have to add them. Also, you can't cover junction boxes they have to be accessible inside the cabinets.
Adding an answer because it would have been quite a long comment...
I knew I had seen "brick clips" before, but I'm not sure either style would work for you.
This kind is made to "hug" the top and bottom of a standard brick, so probably will not work for you, but at least you know it's available...
There's also this style that has little "ears" that you use to wedge it into the horzontal mortar lines. These could work, but I'm not sure they will support the weight of tools, and may easily pull out. I've only seen them used for Christmas decorations.
My goal here is to show you what I've seen, so maybe you can use them as search points for something that will work.
Best Answer
As long as the fireplace draws well you won't have impossible & ugly staining of the marble, so go for it. A rough base is great & will provide the best holding power, an uneven base is bad & needs to be leveled for a uniformly even coat of Polymer Modified White Thin-Set or Mortar...white so the marble doesn't get stained from the backside by your choice of adhesive. This area shouldn't get anything more than warm with a raging fire going.
If you have room for 1/4" or more cement board then great, but be conscious of screw (Tapcon) depth not entering the fire chamber & don't just mortar the cement board on. Screws should only go into the bricks mortar joints & not into the bricks themselves.