Hello I have a 3.5' X 5' space in the basement bathroom where I want to install a tile shower. There is a brand new 3 piece shower drain there right now that is flush with the concrete on the bottom of the drain. The concrete already has a slope in it to the drain that starts out at about 1/4" bubble on my level but the last foot around the drain it steeply drops into the drain. At the furthest wall it's 2 1/4 inches higher then base of the drain. From that wall it's 5/8" drop at about 26" inches then the last foot the bowl makes the last 1 5/8" drop is all in that last foot around the drain. Is that steep bowl around the drain too much of a slope to make this work right with the membrane layer? can this be even out with the bed above the membrane? or do I need to *gulp* jackhammer and level the floor then do the preslope layer etc etc. Thanks fellas.