Now let’s learn how to build a shower stall using CPE membrane. Shower pan liners need to be waterproof and this stuff helps a lot. Shower pan liners can be a few different things. I like to use my own mortar mix and rubber plumbing liner to make a perfect fit in any shower stall.
This is a special kind of rubber that will make a waterproof seal. This is sold at most plumbing stores. You will need to remove the clamping ring from the drain base, but leave four screws sticking up.
One really big rule about the CPE membrane is that it can’t have any cuts or holes in it anywhere except when we cut out the drain hole.
Adjust the membrane so it fits well into the shower pan. Fold it in corners and run it up over the sides of the pan. You can secure it with nails up high or even on the outside of the pan walls, but it needs to be watertight inside the shower pan. The curb is the same. It can be nailed outside of the shower pan.
Now feel where the screws are through the membrane. You will want to cut a small hole in the membrane over the drain and also over the screw holes.You can cut it with a utility knife.
Try to keep the drain hole small. Only include the screws for securing the clamping ring.
Next, put the clamping ring back on and tighten down the screws to make a good seal. There are four tiny holes in the clamping ring called “weep holes”.
These help remove moisture that gets caught on the membrane surface over time. It’s best not to use adhesive when you’re installing the clamping ring. This can prevent moisture from escaping. The pressure from tightening down the screws is good enough.