2. Terminology

Acroterion

A low wall at the edge of the roof. Below 30 cm in height, the acroterion is said to be low. Above 30 cm, the acroterion is said to be high. When the acroterion is not intimately linked to the structure, it is said to be floating.

Adjuvant

Chemical used to modify the rheological characteristics of asphalt to increase the wettability of the filler.

APP

Atactic polypropylene, a thermoplastic polymer that can be added to bitumen, improving its elasticity and yield stress. Materials based on bitumen + APP do not bond to molten bitumen, but they weld very well to heat and resist heat better than bitumen alone. In France and elsewhere,...