05/08/2018 Rainscreen cladding can be fabricated from metal sheeting such as aluminum, stainless steel, zinc, copper and so on, or can be a formed from metal composite materials (MCM) which consist of two skins of metal (such as aluminum, or ACM) bonded to either side of a lightweight core such as polyethylene (PE) or polyurethane (PUR), a profiled metal core or a mineral core. Other materials, such as terracotta, brick slips, stone, timber and so on are also used.
There are two basic types of rainscreen:
- Drained and ventilated rainscreen claddingsystems allow any penetrating moisture to drain or evaporate and vent to the outside. In this case it is necessary to detail the façade so that any penetrating water cannot cross the gap between the rainscreen and the internal wall construction.
- Pressure-equalized (PE) rainscreen claddingsystems allow the movement of air between the inside and outside of the rainscreen. This equalizes the pressure across the rainscreen so that water is not driven, or sucked through the joints.
The difference between the two systems relates to how much water can penetrate the joints, with drained and ventilated systems allowing more water to penetrate. However, the definitions are relatively vague, and the distinction has become somewhat blurred.