Watertightness is achieved by means of a drained cavity created by placing an open-joint cladding at a distance from the support element on its external side. This solution encompasses all façade that incorporate a drained cavity, whatever is the support element made of. Especially typified solutions are those in which the support element is made of either brickwork or concrete with an insulation layer over its outer face (a rainscreen with a heavy inner layer); or those with a post and rail structure of simple profiles as a support for the inner layer (a rainscreen with a light inner layer). As it happens with the ETICS solution, from the functional point of view, the most relevant differences between these two variants are: - the lack of mass that affects acoustics and thermal inertia; - the possible air leaking when using dry construction.