1. Water's modes of action

1.1 Climatic loads

These are the charges due :

• to rain and hail;

• on snow ;

• and wind.

In other words, those that mainly affect roofs, as defined in the "Snow and Wind" regulations.

They are based on statistical studies, but may be exceeded periodically or exceptionally.

• Rain

  Repeated rainfall can cause damage to exposed, unsealed structures, as water can degrade open-porosity and/or cracked materials, and corrode the steelwork of exterior walls. This is obviously the case for façades...