Drive a nail into the floor every 8 12 inches 20 30 cm so the tar paper stays in place.
How to make a shower floor.
Lay a large sheet of tar paper on the entire floor of your shower pan and smooth it out as flat as possible.
The top of the drain should be 2 inches above floor height and you want to mark the walls and curb to a height 2 3 4 inches above the floor as a guide to the amount of mud you need to maintain a 3 4 inch slope.
Pour mud into the shower pan mixing it with a trowel as you go to get rid of air bubbles.
They re cheap easy to install and immediately add texture to your floor which significantly reduces your chances of slipping.
The easiest way to make your shower floor less slippery is to add traction by installing an anti slip shower mat.
Diy step by step instructions on how to build a mortar shower pan.