Hi Dominick,

I am installing a shower in my basement.  The floor is concrete.  The concrete is newly poured, polymer reinforced and extra hard.  I needed to build a drain for the shower – that’s why the concrete is new.  I installed the sandmix for the pre-slope on top of the concrete, but didn’t use thinset as a bond.  I am not sure if thinset is a must.  Also, after finishing the pre-slope and letting it dry, the surface is still a bit sandy to the touch.  It doesn’t have that glassy look and feel you see on all the youtube videos, nor is the finish like what you get from regular concrete.  It would be nice to know if this is okay, perhaps normal, and whether I can proceed with the liner install, or worse, I gotta redo the pre-slope.  Or, perhaps as an alternative, coat the pre-slope with  thinset or some polymer finish to create a surface finish that is not sandy.  It would be helpful to get some informed feedback.

Gord