2. Problems specific to flat roofs

2.1 Movement of concrete supports

The pathology of waterproofing on concrete slabs and acroteria walls is mainly due to dimensional variations in the substrate. The causes of these disorders are of mechanical origin, such as excessive deformation of the floor slab and acroterion as a result of differential settlement of the structure, shrinkage during drying of the concrete or creep of the latter.

2.2 Thermal shock

These also cause shearing disorders at floor level, "sabre-rattling" at acroteria,...