MEH/ Kennerson
Bathroom, Portland Maine
You'll notice throughout all of my projects a greenish membrane over the cement board, and directly under the tile. It's the only shower system I'll use any more for a standard shower. It's a product called Hydroban, made by Laticrete. Unlike most conventional showers, the only waterproofing is under the pan, and up the walls about 12". beyond that, it's generally a vapor barrier behind the cement board. In my showers, the waterproofing, as you can see, is surface applied, and goes atleast to the showerhead, and usually to the ceiling. This exponentially increases the longevity of any shower I install, being that the only thing to get wet is the tiile and grout. There's no way for water to collect in the mortar base, because it's isolated by the membrane. Also, unlike sheet membranes like Kerdi, it's completely seamless, and provides for a complete one piece waterproof envelope.