How to Tile a Hot Mopped Shower Pan
Below are some general steps for tiling after the hot mop of the shower pan.
• Once the hot mop is complete the mud for the tile setting bed must be prepared. We have seen most mud beds floated with a premixed mortar or a custom mix of three parts sand and one part Portland cement. However, before floating the mud bed over the hot mop make sure to keep the weep holes at the base of the drain protected with gravel or crushed tile (read our article on Weep Holes to learn more).
• Also, most local codes call for the mud bed to be reinforced at the approximate center of the base. This is most easily accomplished laying a custom cut piece of metal lath over the floor before packing your mud.
• Once the mud setting bed is complete the wall moisture barrier is put up on the walls.
• Start by flashing the water barrier (typically asphalt felt paper) over the sides of the hot mop so that all moisture flows into the shower pan. The backer board or wall float should come down to your setting bed on the floor. Make sure to not puncture the hot mop below dam level along the walls. This means no screws, nails, or staples below the dam level—puncturing below this level can compromise your shower’s water threshold (think flood levees or river dams with a hole half way up—not good).
• Once the mud is dry apply the thinset and tile. Once the tile has been set you can apply the grout and sealer.
• Once the grout and sealer have been applied, the shower pan should look like the diagram below. Note that the same steps apply to vinyl liners as to hot mopped shower pans.