Traditionally Wet Rooms are waterproofed (tanked) rooms usually equipped with a walk in (level entry) shower. The wet room itself becomes part of the shower enclosure, with a shower drain inset into a gently sloped floor in place of a conventional shower tray. More recently with increased awareness on the importance of controlling water, most new bathrooms are required by councils to be treated as wet rooms - requiring that the total bathroom floor is tanked (waterproofed) regardless of shower type or floor slope.

Tanking is a waterproofing procedure carried out in bathrooms, wet rooms, shower rooms and sauna/steam rooms. it is installed over either timber or concrete flooring prior to tiling and protects the building against moisture migration and leaks (steam, shower spray, etc). Contrary to popular belief, virtually all tile installations are, or will become over time, moisture permeable. If not controlled properly, moisture will migrate into the house structure potentially resulting in mould growth, rot and depending upon the type of house possibly even structural damage.