QUESTION

When you are pouring you mortar for on your shower pan how thick do you want it before laying of tile

ANSWER

ANSWER - First of all, the way you construct a shower pan is to first apply a pre-sloped mortar bed to establish a slope to the drain of 1/4" per foot.  You can float over a concrete substrate or nail on metal lath over a wood subfloor.  Then you have to waterproof the pre-sloped mortar bed with either a liquid applied membrane or a sheet membrane. Then you float a dry-packed mortar bed over the pre-sloped membrane to a thickness of at least 1.5" thick.  The mortar bed should have wire reinforcement fabric suspended within the mortar bed if it is a shower pan area larger than 65 square feet.  Otherwise you can leave off the wire reinforcement. Per ANSI A108.1A-2017.  So after installing the tile the slope to drain should be a minimum of 1/4" per foot.