Install Drain
Just as important as choosing the right shower drain, is installing it correctly for the chosen application. In this case, if you know what water resistant barrier you will proceed with, then your shower drain will be a key part of the waterproofing method you have chosen.
Raised Foundation
Perhaps the easiest of shower drain installations will be where the bathroom is situated on a raised foundation. After demolition, the sub-floor is exposed and either consists of plywood or running boards that are nailed to floor joists. A straight-forward installation will only require precise cutting around the shower drain for removal and access below the floor. You would then need to cut to size a patch piece of plywood to go over the access area. An alternative would be to cut the shower drain from below the house, then install piping leading into the trap. The next step would be to either install the shower drain over or flush with the sub-floor.
To get a better understanding of the plumbing pipes under a raised foundation meet up with the shower drain, take a look at the video below.
Second Floor
On a second floor shower installation, you may or may not have adequate crawlspace to reach the drainage pipe. You can either reach the bathroom sub-floor by entering through the first floor ceiling, which could be costly, or you can make a precise access hole around the shower drain. The process is the same as with the raised foundation, your final result will be a shower drain that is installed over or flush with the sub-floor.
See the following for a first hand look at a shower drain installation in a bathroom located on a second floor.
Concrete Slab
If your home is built on a concrete slab, be prepared to break into the cement floor to properly install your shower drain. In order to expose the drainage pipes leading into the shower drain and install the necessary replacements requires that cement over and around the area be cut out or broken and removed. Doing so will allow you to inspect and determine if any leaks or deterioration has occurred. After installing a new pipe from the drainage system to the trap, the shower drain will then be installed and set at floor level. Cement is then laid in the open area and paved to a leveled floor finish.
See this example of a shower drain installation in a concrete slab.
Bath Tub
If you don’t want to give up the opportunity to bath in a tub, then prepare for a reasonable amount of effort to install a shower drain. With a new bath tub installation, you can install the necessary drainage pipes from trap below the floor up to the drain and overflow. You can use a complete assembly, which contains the enters from the exterior of the tub and is fastened inside the tub.
This is a step through a bath tub shower drain installation.
Shower Pan
If you have chosen to install a shower pan or shower tray instead of building up a shower pan, then a 2-piece PVC shower drain would be your best choice. With a new shower pan installation, you have access to the bottom where you can easily connect the pipe leading from the trap and into the shower drain. Afterwards, you can complete the installation by attaching the top portion of the drain
Here is a great example of shower drain installed on a shower pan.