Sheet Membrane or Liquid Applied
Sheet and liquid systems both work, and they fail in different places. Products compared through walk in shower installation lakewood ca nexusphiladelphia are judged on the corners rather than on the field, because in every Lakewood shower that has ever leaked the flat wall was fine and the change of plane was not.
Sheet Membrane
A bonded fabric or polyethylene sheet set into thinset over the substrate. Its thickness is guaranteed by the factory, which is its main advantage: it cannot be applied too thinly. It demands a flat surface, careful overlaps, and preformed corners, and it is unforgiving of a lump of thinset left under it.
Liquid Applied
A rolled or trowelled coating, usually two coats in contrasting colours so coverage is visible. It handles awkward geometry, penetrations and shower niches far more easily. Its weakness is film thickness, since a coat spread thin to make the bucket stretch looks identical to a correct one once dry, and it is exactly at the corners that people run short.
Corners, Curbs and Penetrations
Both systems need reinforcing fabric at every internal corner, at the wall to floor junction, over the curb, and around the valve and the mixing valve body. Preformed corner pieces exist for a reason. Where a bench meets a wall the detail has to be continuous, because that junction moves and is under standing water.
Do Not Mix Systems
Every manufacturer warrants a complete assembly: their membrane, their band, their sealant, their drain bonding flange. A liquid coating over another maker's sheet corner may well perform, and it also means nobody stands behind it. Choose one system, buy the whole kit, and keep the receipts with the flood test photographs.
What Goes Behind Either
Cement board or foam board, never plain gypsum, fastened at the spacing the maker specifies with the joints taped and treated. Foam backer board is lighter, insulates and is already waterproof, at a higher material cost. On a wall that has to carry a heavy grab bar, the blocking behind it matters more than which board is on it. Plain gypsum belongs nowhere inside a shower, including the ceiling, and finding it behind a tiled wall during a repair is reliable evidence that the whole assembly needs replacing rather than patching.