The 5 biggest mistakes I see people make when tiling showers

1) Not Waterproofing Correctly

This is by far the most important step when building a shower. If the waterproofing is done incorrectly, the results can be catastrophic. When choosing a waterproofing system it’s best to find the companies step-by-step walkthrough on how to install it properly. Schluter, Wedi, and Laticrete have videos on YouTube and their websites

2) Cutting in the niche too early before laying out the tile and having sliver cuts around it

Cutting in the niche too each leaves the possibility of having silver cuts above or below the opening. What I recommend (if you're installing the shower base first) is to install the shower floor tile and after, you can lay out exactly where a full tile will end and where the bottom of the niche will begin. From there you can install the niche to the correct height!

3) Not spending time on the layout and having sliver cuts in corners and against the ceiling

This is another layout-focused tip. Not planning where tile will end or how they will wrap corners can cause unsightly slivers in said corners, ceilings, and against niches. To avoid this, it is best to lay out your wall tile on the floor using the grout joint of your preference and transfer those measurements onto the wall. If you notice that there are slivers anywhere, try to shift the layout to avoid them. You can do this by cutting the bottom row to bring your layout lines lower, shifting the pattern to the left or right, or changing the pattern in which you're laying. For example, if laying tile in a ⅓ running bond pattern and it leaves you with a sliver in a corner, it may be advantageous to change the pattern to a ½ brick set pattern.

4) Not using proper techniques and standards when installing tile and having less than sufficient coverage behind the tiles

Not correctly setting the tile with proper coverage is also a giant mistake I see people make. A very popular but incorrect way to adhere tile to the wall is with the dot method, this method will leave many hollow spots behind the tile where mold and mildew can grow. If set correctly, you will be using a properly sized notch trowel while directional troweling and finally collapsing the ridges to achieve 95% coverage in all wet areas. 

5) Not polishing cut edges of tiles

A crucial step that I see a lot of homeowners and installers skip is polishing the edges of the cut tile with a stone or diamond pad. When cutting or snapping tile it has the potential to have a jagged, chipped, or sharp edge. For $20 you can buy a nice diamond hand pad that will make short work of any chipped edges for ceramic or porcelain tile.