Hello. I've received conflicting advice on whether the bottom horizontal piece of a shower enclosure should be sealed with silicone on the outside only OR both on the inside and outside. See images. The original installer sealed both inside and outside when the home was built. It lasted 15 years before it started to mold on the inside. I removed it, cleaned it and re-installed (siliconing the inside and outside) and it only lasted a year before deteriorating again. Should I only be siliconing the outside?
