Shower Pans For Tile
In order to keep water in the shower and not somewhere else, it takes installation of shower pans for tile in any ceramic tile shower. It may appear that the floor of a shower is enough to keep water where it belongs, but such is not the case.
Cracks in the grout, especially where walls meet or where the walls and the floor meet, are just the place for water to get into the base of the shower and from there to other parts of your house except for whatever method is used to stop the water.
Here are some ways that water is kept in the base of the shower...
Masonry Shower Pans For Tile
The traditional way to build up a shower base pan, after all the floor must slope to the drain, is to use mortar to build a floor. Mortar works well because it's cheap, not overly bothered by water and it can be made to any size or shape.
What usually happens is two mortar layers are put in at the slope desired. That's simple enough to see as you look at the floor of a shower.
The not so simple part is the actual layer that stops the water, because the mortar won't stop it.
What stops the water in most cases is a layer of vinyl sheet that is put in between the two mortar layers. That layer gets glued to a special drain too.
The drain has not only the opening you see at the floor but also another opening lower that gets routed to the drain. That lower level drain takes the water that makes it to the liner membrane.
For sure lots of other liner materials have been tried and used. Some, like hot-mopped asphalt, are still used but the built-in vinyl sheet seems to have won out.
Foam Shower Pan
Instead of the masonry base, some installers opt for the specially built foam bases that are ready to tile as soon as they are set in place. Leaders in this type are the Tile-Redi brand ready to tile showers. Other brands offer similar dense foam pans. What these offer is a waterproof top layer in a dense foam base and curb. So one can actually put tile right on the base as soon as the base is in place.
That makes for a less complicated installation.
It also means you do not get a water-soaked base between floor and liner as you do with the mortar base.
The only soaked part is just the thinset adhesive used to stick the tiles in place.
Downside to these is mostly just the far higher cost for parts as compared to mud pans.
Solid Surface Shower Pan
It may be tempting to just put tile over a typical solid surface shower pan like an acrylic pan or a fiberglass shower pan. This will not work for a shower pan installation. The pans not made for tile lack the rigidity or just plain stiffness that it takes to keep the tile in place.
One of the reasons to get a tile shower is to just get that solid feel that you get with tile showers. Some shower pans, not for tile, just simply move and bounce and are quite an adventure as you wonder whether you get to stay in the shower or find out what's below. This type of bouncy floor will not be one that keeps tile solid.
You have shower floor options. Several types of shower pans for tile will work quite well. On the other hand, some shower bases may look like a base for tile but will end up just costing you trouble and money instead.