Your installation manual will tell you what materials you should, and shouldn’t finish your fireplace with. It will tell you clearances for combustibles, including how high your mantle should be above your fireplace.
What it won’t tell you, is how the cut of tile can affect your fireplace.
Your fireplace will heat the finishing area around it. When choosing materials, such as tile, it’s best to make sure there’s adequate grout area. Or at least, separation between large tiles.
If you choose to finish with one slab of marble (or a similar stone) the heat will move the tile slightly. This has resulted in broken tile; and unhappy homeowners.
If you cut your tile into pieces (even larger pieces) your fireplace should be fine.
In one case, we had installed a linear fireplace, it was finished with a single slab of granite surround by others. The granite cracked in the same spot multiple times. We only realized after the 3rd or 4th piece of granite was replaced that when the floors had been installed, they were on a little bit of a slant. So the granite had been installed with a gap to hide the unevenness of the floor, leaving about ¼ of an inch exposed. The heat got to this area and cracked the granite.
The best way of avoiding these problems without sacrificing your wants is to opt for a fireplace with a large opening. The bigger the distance between the fireplace burner and the slab of tile, the better.
Units to consider with a large opening are:
Town & Country TC54
As always, consult your manual, and talk to your sales person about your finishing materials.
*The unit in our header is the DaVinci, a power vented fireplace with safe touch glass.