I tore out some old masonry and it left behind some poorly mounted sheetrock and some uneven brick. I want to have a 12" tile border around the fireplace opening with a wood trim mantle around that (so the tile doesn't need to be flush to the sheetrock at all). I will have finished sheetrock above the mantle.
Issue 1: Mounting sheetrock to the wall- there is a 1"+ gap behind the sheetrock. I can feel a stud horizontal in the middle of the rough sheetrock panel, so I am going to need to add some more structure there. What do I add? Non-flammable framing? Like steel? What is the best way to tie them into the vertical framing outside the fireplace?
Issue 2: Getting Hardi-backer on the uneven brick. I need to level the surface around the fireplace opening and mount hardi-backer to it. I was thinking I would do mortar in a few layers with some chicken wire to reinforce it and prevent it from running down, and then fasten the hardi-backer on with masonry screws after drying and sanding flat.
Suggestions? Code violations?
This is in Portland, Oregon.
EDIT: the bricks that look like vents are NOT vents. They can be removed.