Most make this layer at least 1 thick at the drain and again slight slope so the layer is thicker at the walls.
Shower pan on a wood floor plywood thickness two layers.
The second layer is poured placed on top of the installed shower liner.
The minimum thickness allowed for ceramic tile installations is two sheets of 5 8 inch thick plywood.
Form the curve toe nail 2 6 blocking at the base of shower on interior walls to support the vinyl liner.
The plywood must be exterior grade for all wet areas and it has to be installed in such a way that the joints between each layer do not line up using what is known as a stagger pattern to keep the pieces from ever lining up.
After you have put down a double layer of plywood to provide the base for a custom walk in shower pan you need to cover the subfloor with a layer of tar paper in this case referred to as a vapor.
This top layer is typically thicker to provide strength as this is the layer that will be tiled and the finished floor layer of your shower pan.
Cdx plywood is traditional wood plywood made from thin layers of lumber known as veneers.
Cut the top of the drywall at 6 ft.
Cdx plywood should be a minimum of 7 16.
Above the plywood floor to allow for the slope fill and two layers of 3 ft.