I have been doing a lot of reading and it seems there is a lot of information out there that has sorta confused me, so I thought I would ask you guys and hopefully you can give me what I need to know. I am going to be tiling a small bathroom that has sheetrock. (FIRST TIMER DIY'R) It will not be around the back of a shower/tub as its fully enclosed. But the wall that joins it I will be tiling with a tile that has glass and rock in it. It will only go 42 inches up the wall and will also go above the vanity. Do I have to replace my sheetrock with backerboard and if so, what if I cant cut it all out as some I cant hit my studs as the placements are not reachable. Would it be ok to leave some sheetrock? I think its my understanding the reason to replace the sheetrock is because of moisture. Is there something I can use that can seal the sheetrock? I cant place the backerboard over my sheetrock either because of my counter top backsplash isnt wide enough and it would hang over it and because of the wall that joins my shower is framed out and would stick out over the frame. This question I guess goes along with my kitchen project too. I just hate having to cut out my sheetrock and replace it if I dont have to BUT I dont want my tile to be falling down or mold and mildew behind my tile. Thanks so much for the advice.