For our new shower we have decided to use the Schluter Kerdi Shower System. It is not cheap (around $550 to $600 depending on the size) but it is one complete kit that comes with pretty much everything you need to have a leak free shower. In our case because we were dealing with a previously leaky shower we wanted to ensure that not a single drop of water would get through.
You can also purchase individual components of the kit should you want to do some parts yourself (like make your own sloping floor). There are also additional items that you can add like a corner bench etc.
Before you attempt to install this kit it is really important that you read all the instructions. The kit comes with a full installation booklet and DVD and additional resources are available online.
Let's get started shall we?
First you install the perfectly sloped floor tray to line up with your drain. It is made of polystyrene so you can easily cut the sides down to the correct size. Using unmodified mortar you attach the tray to your sub floor.
Once the tray is in you can start to add the Kerdi polyethylene waterproofing membrane and vapor retarder.
Start with all the seams and the inside corners that do not go against the curb. We measured and cut ours before installation. It's really important to make sure that you smooth out all the Kerdi seams, especially in the corners where there will be multiple layers. You do need to apply some pressure to do this properly.
Once all the seams and corners are in you can apply the Kerdi membrane to the walls. Again we measured and cut our pieces before installation. This is two person job to attach and should be approached like wall paper. Start from the bottom/top middle edge and work your way up/down and across. Again it is really important to smooth out all the excess mortar and a fair amount of pressure needs to be applied to do this.
Once all the Kerdi Membrane is on the walls the drain flange is ready to be attached. Measure and cut your last piece of pipe to connect the drain flange to the p-trap below the sub floor. Apply the glue to the pipes and mortar to floor and attach. Eek! This part had us nervous but everything seemed to fit together really well.
The last step is to attach the curb (again is it polystyrene and can be cut in length and height). We cut down the height of our curb so that we would have one full tile on the outside edge. Once the curb is attached you attach the last 2 inside corners and the 2 outside corners. Then the Kerdi membrane can be added to the curb and then finally the shower floor.
Viola! The shower kit is complete. You need to wait 24 hours to allow it to dry before you can tile.
My outline above makes it seem really simple and easy. Let's just say it's about as easy as installing a shower kit. While using the kit did simplify the process it did still take about 10 hours to install.
When it was done were feeling really triumphant (and exhausted) that this phase was complete. It is starting to look like a shower.
