I just finished putting up my backerboard around my shower pan this weekend. According to the instructions with my shower pan, I put a bead of 100% silicone caulk between the base and the bottom of the backerboard. Unfortunately, a fair amount of silicone seeped out and dried up along the perimeter of my shower base. I've scrapped some of it away, but it's almost impossible. There is a thin coat of silicone all along the shower base and where it meets the backer board. My question is, can I put a waterproof membrane (KBRS Shower Seal which is similar to redgard) over the silicone and or a kerdi band around the perimiter before i tile? I'm concerned that either/or will not adequately stick. Or should I just go ahead an start tiling with thinset and assume it's good. I was originally planning to use the shower seal along the gap, but now I'm not sure that's going to work.
I would suggest you use a little piece of Kerdi, Nobel TS or equivelant and apply the membrane to the shower base with Nobel 150 or Kerdi fix. Attach the Kerdi to the CBU with non modified thinset or the Nobel TS with modified or un modified thinset.