What is the purpose of a rain screen in a building?

The purpose of a rain screen in a building is primarily to allow moisture to drain away. The rain screen system is designed to create a gap between the outer cladding of the building and the structural wall. This design serves to manage water penetration effectively. When rainwater hits the outer layer, it can freely drain away, preventing moisture from reaching the underlying materials. This drainage helps reduce the potential for water accumulation, which can lead to issues such as mold growth, wood rot, or deterioration of the structural integrity of the building.

While rain screens might indirectly contribute to insulation, offer some aesthetic appeal, or provide minimal structural support, their primary function revolves around water management and protection against moisture infiltration.