Tile – How to add tile to the fireplace

ceramic-tilefireplacemasonry

[UPDATE: After reading the question and answers, please see this blog that shows how the fireplace renovation was completed.]

I am getting ready to begin tiling part of my fireplace. The current finish is a wooden mantle surrounding a masonry façade that runs to the outside edge of the firebox.

This is the current appearance.

fireplace wide

I plan to place ceramic tiles over the masonry portion of the façade. I will probably use stoneware tiles (in an arts and crafts style), either 4×4 or 8×8 for the bulk of the field, possibly with decorative tiles in the corners. (I realize I will have to cut tile, use other sizes, use border tiles, or adjust the moldings to deal with the slightly wider upper field.) I will also check with the manufacturer/supplier to ensure that they are suitable for fireplace installation.

The surface of the masonry façade appears to be a cement-like finish that has been trowelled to look like brick. Here is a close-up.

fireplace mid

The surface seems very solid ith no areas breaking away except for minimal chipping in a few places at the very edge. The surface also seems to be painted. There is no significant flaking or loose paint. See below.

fireplace close

I am not sure what is below the cement-like surface. I suspect brick, but am not certain. The fireplace was built around 1905 and possible renovated in 1999, but I am not certain.

My questions are about installation:

1. Do I have to remove the cement surface before tiling?

2. Do I have to strip the paint?

3. What mortar, mastic, adhesive or thinset should be used to hold the tiles?

Obviously, I would like to minimize the prep work but want a strong adhesion.

Best Answer

Cement surface and even paint (scarifed with 50 grit belt sander or similar) can stay, if both are well adhered..

An experiment is in order:

Observe the removed thinset:

  1. If it cleaves off with no embedded paint, paint is very well adhered, but may be too slick, scarify through paint layer to cement before tiling.
  2. If some paint embeds, and some thinset remains on surface, it is a good interface layer, proceed with tiling.
  3. If paint cleaves off easily, remove paint fairly thoroughly before tiling.

In no case use a premix mastic thinset or other adhesive to adhere tile.