Ventilated rainscreen cladding is a system of cladding in which the stone panels are used as part of a system that shields the majority of the supporting structure from direct rainfall. It combines a cavity and drainage system behind the panels to remove any moisture that gets past the rainscreen panels. There are two types of rainscreen panels:
The individual stones can either be fixed direct to a backing wall or more typically to a framing system comprising of a grid of vertical and horizontal aluminium profiles.
Ultra Thin Cladding
There are a number of different methods for attaching very thin stone onto a strengthening substrate, these include the honeycomb aluminium, ceramic and lightweight concrete.
The designer needs to be aware of the various movements; thermal, dead & live loads, settlement, moisture and wind loadings, between the structure, the framing system and the individual stones.
Joints in a rainscreen panel system are designed to permit air to circulate behind the panel and to allow moisture to drain from the cavity.
The cavity between the stone and the backing structure will incorporate an air gap, insulation and a breather membrane.
Cavity Fire Stops
The cavity design needs to incorporate cavity barriers to prevent the spread of fire both vertically and horizontally.
The insulation needs to be non-combustible, rot and vermin proof and non-absorbent. The insulation may have a foil layer to act as a vapour control layer or a breather membrane applied to the outer face to control condensation.
We recommend that the stone and the cladding contractor is selected as early as possible in the project programme.
The designer should be aware of the recommended lead-in period for the supply of stonework cladding.