Improper Shower Installation

You’ve hired someone to build your tile shower in your bathroom, but how do you know he or she’s doing it correctly? How do you know that it won’t leak? Most homeowners don’t know all the in’s and out’s of remodeling their bathroom. Sadly, the contractors they’ve hired don’t always know either, or worse, they simply don’t do it right.

Here’s some of the reasons that showers tend to leak:

  1. Why cut the shower liner if you don’t have to? When dealing with inside corners of a shower, they should be folded rather than cut. If you have an outside corner, you will have to cut and patch the corner according to the liner manufacturer’s instructions. It is possible to cut the corners, patch them properly, and have it not leak. How do you know if your shower leaks?
  2. Most of the problems in this regard have to deal with how the curb is dealt with. The shower pan liner must go up the wall 3 inches above the framing of the curb, according to Tile Council of North America (TCNA) standards. It also need to go up and over the curb to the non-wet area (the front of the shower). Where it gets tricky is at the corners of the curb because you normally have to cut it to get it to fold over the framing. The shower pan companies make pre-formed corners for just this purpose. Make sure you, or your installer, use them.
  3. What good does it do to run you shower pan liner 3″ above the curb if you put a nail in at the bottom? If you see nails below the curb level in the shower, it’s time to look for another tile setter. Keep in mind, if you are using a waterproofing over the surface, like Schluter’s Kerdi or Custom’s Redgard, this doesn’t apply. But if you are doing a mud pan with a liner underneath the mud, nailing below the curb level is a no-no. In regards to the curb, there should be no nails or penetrations of any kind on the inside or top of the curb. Nails, staples, or glue can be used to attach the liner to the front, non-wet, side of the curb.
  4. If someone is using cement board on the top, or inside, of the curb then they do not know what they are doing. How do they plan on attaching the cement board to the curb? The proper way to do it is with metal lath and a sand/cement mix- the same thing the shower pan is supposed to be made out of.Exception: If you are using a surface waterproofing such as Schluter’s Kerdi fabric or Laticrete’s liquid Hydroban then it’s OK to nail or screw cement board on the curb as the waterproofing will go over the top of it and not be beneath it.
  5. While this doesn’t cause a shower to leak it certainly will tell you whether it’s leaking or not. A flood test is when you plug the drain and fill the shower up with water to just below the curb. If you have a leak anywhere, you will know before it gets tiled. Put a mark on the wall and wait 24 hours. If the water is lower than the mark you have a leak.

    Insist on a flood test. Write it into the contract if necessary.