Can i use Self Leveling cement (plus primer) over hardiebacker that has been cocered in redgard/waterproofing membrane? Or do i have to use mortar (like for a shower)? I am trying to raise part of my kitchen floor where the old cabinets were and the new cabinets are going. It is about 20 sq...

I need to raise a concrete entryway floor to bring it close to even with my kitchen floor, and then I need to put sheet vinyl on both floors. There is a 1 1/2 inch difference in height between the two floors, and the cement entryway has radiant heat water tubes embedded in it, so nailing is not...