Abstract: A shower base system and installation method thereof. The system includes a shower base with an integrally formed tapered standing sidewall corresponding to each existing structural wall against which the base is installed, and a waterproof membrane covering and extending upwardly along the structural wall from a bottom point at least partially covering the standing sidewall. The system can be installed with the sidewall directly abutting drywall or other outer surface of the structural wall, covered in turn by the membrane with tiling applied thereon, or, alternatively, with the sidewall directly abutting a bottom plate and studs or timbers of the structural wall, with drywall installed over the sidewall and the membrane covering the drywall, and tiling applied on the membrane.