Ahhh and here we are...up until this point most of the renovation was pretty straight forward. It was laborious, but still straight forward work. My initial plan when I started was to get to this point and leave the crazy shower building stuff to the pros (My initial initial plan was to hand a check over to someone and have them do everything). I figured that was enough for me and I had no idea what the hell a shower pan even was. However, when I got to this point my feelings changed, I became emotionally involved and I did not want to come out of the game just yet. I already backfilled cement, mixed and thinsetted cement boards...I was in too deep now. Also the guy I planned on doing this was pretty backed up, and I didn't want some random coming in and screwing it up. I could just do that myself. I would attempt the unthinkable for a chump...BUILD A CUSTOM SHOWER MORTAR BED!! A lot of my contractor friends even told me that they never attempted this before as they had a "dedicated guy" they would call in for a feat of such magnitude. This intimidation only served as fuel.
I couldn't use a ready to tile shower pan since I needed a custom size for my space. Those things are not cheap either, like $500-$600, but probably worth it if you have a standard dimension that fits one. These 2 sites display pretty much everything you need to know to build a custom pan:
How to build pre-slope shower mortar bed
Step by step building tiled shower curb
In a nutshell those links describe EVERYTHING I did. If you want to see the perils I endured than check it out, there is no use for me to re-hash all here. Even a nice write up on How to mix the mud properly. In addition I was armed with a few books, and after plenty of research I felt I was ready. To begin I started by putting down a slurry of thinset on the concrete base for the pre-slope mortar bed to bond to. I than used the basic Home Depot Sand Topping Mix along with some general purpose sand for the pre-slope mud. I quickly learned that I should have used simple play sand since it is much easier to work and shape. I would not make this same mistake on the more important final mortar bed (which at the time I was "unsure" I would even attempt). Once cured I was able to successfully bounce a golf ball off the pre-slope, proving it was officially bonded to the concrete base (A contractor friend alerted me of this nifty trick). Looking back I would have definitely used Pre-Pitch
, but at the time i didn't know of its existence.
Next I put on the PVC pan liner following all the necessary instructions. I was tempted to try the slightly more expensive chloraloy membrane liners found only at plumbing supply shops. But I just went with what the big stores had. Chloraloy is supposedly much easier to work with, holds its form better, and does not bulge out your cement boards since they lay flat against the studs. I heard some dudes actually notch out the studs to compensate for the PVC liner. With chloraloy this is not even a concern I guess. Also I would bet you don't even need to add the blocking around the perimeter in between each stud since it holds it shape almost like a self box:
I almost don't even think blocking was required with my PVC liner, but I didn't want to break ANY rules on my first time. Once the liner was installed I performed a 24 hour leak test with an inflatable test ball plug
and failed within 15 minutes. I knew what I did wrong tho, fixed it and re-tested. After 24 hours with water sitting in the pan the water level was exactly the same. Good thing I did the test I suppose.
Once the pan was done, I could finish installing the bottom of the wall cement boards. And yes I made sure not to put any screws low enough to puncture the liner, what do you think I am a chump? Finally mudded and taped all seams and corners using alkali tape and thinset.