ETICS solutions, which are now so common due to the thermal insulation continuity they allow, were already used twenty-five years ago in designs such as the MACBA building. At that time, achieving continuous rendering without joints was not that simple, as the rendering materials were not as good as the ones we use today.
Lightweight solutions for the rainscreen outer layer were barely known. Probably because the architects did not trust this solution, the inner wall was completely covered with a watertight membrane.