A lot of builder-grade homes in Austin have inexpensive wood burning fireplace inserts. These are basically metal fireproof boxes that can be set directly in a 2×4 drywalled wall and vented with a simple metal flue, giving a bit of cozy traditional fireplace feel without the expense of a traditional brick and masonry hearth and chimney. For example:

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. Like this:

A tiled surround for a fireplace insert is therefore 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.

In this case, 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 itself, but could always be refreshed at anytime with a new coat of flat black heat-resistant paint for 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.

Tip ZERO: Tile First!

The best workflow on a project like this is indeed to install the tile first. It’s usually pretty easy to overlap wood trim onto the edges of previously installed tile. In contrast, it is almost 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 challenge was 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. Read on for the tricks.

Tip ONE: Preplan your Plan

Things can move pretty fast once thinset is mixed up and tiles start getting slapped on. So, to prevent slapdash results, it’s a real good idea to be really deliberate about planning 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.

But even if this were a more simple mosaic wall tile install, it would still have been a timesaver to preplan and precut the mosaic mats beforehand. These tile mats in particular were quite thin, and the drywall surrounding the fireplace insert was not plumb, square, or even. So each tile mosaic mat needed to be floated off the wall on an already thin layer of thinset, which starts to dry and skim over immediately after being troweled onto a wall.

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

Tip TWO: Work WITH Gravity

It’s always tempting to start a mosaic tile install from the bottom up, since 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 whatever else might be to hand to install your mosaics from the top down to frame an opening. It’s generally the only way to make sure that all the seams will match up perfectly in the end. In this case, magnets really helped!

The aluminum Schluter edging made for a ready-made vertical brace to support the tile, and keeping everything perfectly level and plumb was made easy by simply holding the metal trim in place with a magnetic level stuck to the metal fireplace surround.

Bottom line? It is devilishly difficult to get any patterned tile to meet perfectly at the midpoint of an opening if you start from two sides and try to work your way up. It is far easier to simply start from the middle and work your way out and down.

Tip THREE: Careful with Corners

This mosaic tile was only 1/8-in thick, which meant that 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. Working from the top down made it possible to make a perfectly plumb-looking tile surround out of an initially kinda cockeyed situation.

Here is what the result looked like after grouting and then with finish carpentry trim for the final mantel surround: