This post describes how to install a mosaic tile fireplace surround with perfect results. You can choose just about any tile for a fireplace insert surrounded by drywall. Mosaic tile is a good choice for lots of visual interest. But mosaic tile for a fireplace surround presents some install challenges. Read on for tips and tricks!

A lot of builder-grade homes in Austin have inexpensive wood burning fireplace inserts. These are basically just metal fireproof boxes set directly in a 2×4 drywalled wall. An insert will give a cozy traditional fireplace feel without the expense of a traditional brick and masonry hearth and chimney.

Since these insert fireboxes are designed to be simple and flexible, they can be relatively easily dressed up with surface design elements to match the rest of a room’s decor. Here is what this fireplace looked like after installing a mosaic tile surround and wood casing.

A tiled surround for a fireplace insert is kinda like a kitchen or bathroom countertop backsplash. It’s mainly a decorative element that can also make a space easier to clean and maintain.

The Challenge

The clients had a livingroom fireplace insert surrounded by bare drywall that was drab and a drag to keep clean of knocks and bumps from tossing logs on the fire. The insert itself was a little knocked around. A new coat of flat black heat-resistant paint gave a like-new DIY finish.

What the clients needed pro help with was making a fireplace tile surround and mantel to match their design vision. It’s relatively easy to just stick some 12×12-in ceramic floor tile on a wall and call it a fireplace surround. It takes a bit more skill and patience to make a mosaic tile finish.

Here’s a “before” look at the bare insert and the rough diagram of what the client was wanting for the final result:

There was already a finish carpenter lined up to fabricate and install the new mantel and surrounding wood trim. So, my job was just the tile.

First Tip: Tile First!

The best workflow on a mosaic tile fireplace surround installation is to install the tile first. It’s pretty easy to overlap wood trim onto the edges of previously installed tile. In contrast, it is always much more difficult to tile seamlessly into previously installed wood trim. If you are constructing a custom mosaic tile and wood trim fireplace surround and mantel from scratch, then install the tile first.

The trick is to install the ceramic mosaic tile and grout for a perfectly centered and even finish on the firebox itself.

Mosaic tile can be difficult to install on even a flat surface without showing seams between the individual tile mats. But gravity is a cruel force for mosaic tile install on a wall. Even a slight sag in any of the tight 1/16-in tile joints will show. And keeping multiple tile mats perfectly perpendicular or level over even a couple foot span can be quite a trick.

Second Tip: Preplan and Precut

Things can move pretty fast once thinset is mixed up and tiles start getting slapped on. You need to plan out exactly which tiles will go where once the install actually starts. This is especially important when you’re working with thin mosaic tiles.

The inside tile perimeter needed to be trimmed out with black metal Schluter edging that would show any incongruities. And the left/right tile margins would have no margin for error since the fireplace insert dimensions were real skinny to begin with. The tile was light blue, and the grout would be bright white. There would be nowhere to hide any unbalanced or even slightly out of plumb bits.

So, preplan and precut. It makes everything easier when you do.

Third Tip: Work WITH Gravity

It’s tempting to start a mosaic tile install from the bottom up. This can seem the quickest way to finish. But if you’re trying to tile an open area with perfectly perpendicular and plumb perimeters, then this bottom-up “easy” approach can result in a cockeyed mess.

For best results, use tape and a ledger board to install your mosaics from the top down to frame an opening. This is how to make sure that all the seams will match up perfectly. Magnets are a nice trick for holding up horizontal tile when installing mosaic around the top of a metal fireplace surround.

Aluminum Schluter edging makes a ready-made vertical ledger board brace to support the tile. You can keep the mosaic tile surround perfectly level and plumb by simply holding the metal trim in place with a magnetic level stuck to the fireplace surround.

Bottom line? It is impossible to get any patterned tile to meet perfectly at the midpoint of an opening if you start from the bottom of two sides and try to work your way up. Instead, simply start from the middle of the top and work your way out and down.

Fourth Tip: Be Careful with Corners

The porcelain mosaic tile for this fireplace surround was only 1/8-in thick. So making the tile completely flush to itself was a real challenge for the corner trim. The trick here was to install the corner tile pieces separately, with some nifty tile saw shaving on the backside to make them skinny enough to lay flat with all the other tiles even with protruding metal trim bits underneath.

Once the perfectly centered top line of tile was in place and the corner bits were squared away, installing the rest of the tile was simply a matter of hanging mosaic mats with tape. By working from the top down, you can make a perfectly plumb-looking tile surround out of an initially kinda cockeyed situation.

The Finish!

Here is the mosaic tile fireplace surround after tile and grout install. You want to use a dense presealed sanded grout mix for fireplace surround tile. This will make the tile surround easy to keep clean.

Here is the final completed project with trim carpentry and paint. It’s a real upgrade over the bare drywall origional!