Hi everyone I am thinking on putting slate over top of my existing brick fireplace.
But I was just wondering if I should do the thinset in two steps, the first step being to fill the grout lines of the old brick to make a smother and more even surface or can I use a half inch nached trawl and butter the back of the slate and the wall and stick them on that way.
thanks everyone
I
Replies
We put slate over brick and used FR stucco mix to level the surface and fill in the mortar joints. If the joints are at least 1/4" deep and the brick is clean, it will work. A coat of acrylic surface bonder on the bricks and mortar is also good insurance. If the brick is crumbly, uneven, painted, or the mortar joints are shallow, you might consider another approach, perhaps tile backer board as a substrate.