Why is the water exposure class important?
A water exposure class is a classification that indicates the degree of water exposure to specific components or structures. It is used to determine the level of protection required and the appropriate materials for the specific application. The classes range from W0 to W3 and indicate whether the components are exposed to no, low, moderate, high or very high water exposure. Depending on the class, different measures are taken to protect the components from moisture or water.
| Water exposure class | Water exposure | Examples of use |
| W0-I | Low – Areas not frequently exposed to splash water | Areas of wall surfaces above washbasins in bathrooms and sinks in domestic kitchens |
| W1-I | Moderate – surfaces frequently exposed to splash water or occasionally exposed to service water | Wall surfaces above bathtubs and showers in bathrooms; floor surfaces in domestic areas with a drain |
| W2-I | High – Surfaces frequently exposed to splashing water and/or service water, intensified by standing water | Wall surfaces of showers in sports/commercial facilities; floor surfaces with drains/channels; ... |
| W3-I | very high – surfaces frequently exposed to splash water/service water/cleaning processes, intensified by standing water | Surfaces of walkways around swimming pools; surfaces in commercial premises (breweries, ...) |
Illustrative representation of wear classes for indoor use

Water exposure class
W0-I = low
W1-I = moderate
W2-I = high
W3-I = very high

En-suite bathroom with a bath, shower and shower screen.

En-suite bathroom with a bath without a shower head and a shower tray without a shower screen.

En-suite bathroom with a bath (no shower head) and a shower tray with a shower screen.

En-suite bathroom with a bath without a shower head and a walk-in shower without a screen.

En-suite bathroom with a bath (no shower) and a walk-in shower with a screen.

En-suite bathroom with a bath without a shower head, a shower tray with a shower screen, and a floor drain in the room.





