I am remodeling our fireplace surround. It had tile around it and I successfully demoed that. Now the "backerboard" is weak in places and I can press it in easily with 1 finger. I am thinking I need to tear out all of this "backerboard". I say backerboard as I don't really know what it is. Should I replace it with wonderboard? Ultimately my goal is to have a paintable fireplace surround, no tile or stone with a modern look. Can I paint the wonderboard as if it were drywall? Can the wonderboard butt up against the fireplace? It is a gas fireplace and has not visable vents in the front, I imagine it all goes up thru the chimney that I know is for sure there.
First step is to check code requirements in your area, as they will vary. Normally, there is a minimum distance to the sides and above the firebox that must be non-flamable material. That includes paint. That distance can be very small or non-existant if you have a gas fireplace with a fixed glass front, a small distance for regular gas and a greater distance if it's set up for wood burning.
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