What happens when moisture penetrates the exterior walls of a commercial building? There are times when water can still go through the weather-resistant protection system of the building. When this happens, it penetrates deep and will not dry easily. The condition keeps the walls wet and vulnerable to rotting, rust and growth of microorganisms. The wall itself is structurally compromised.
Moisture entrapment poses foundation problems, health threats and decreases the building’s performance and durability. Exterior commercial waterproofing systems should include drainage plane systems to lessen the risk of water entrapment.
Water from rain or foul weather often enters the building through a high point in the exterior wall. A rainscreen drainage plane makes a drainage path for moisture to flow through, from the high point down to an exit point in the lower area of the wall. This solves the problem of slow-drying inner walls due to water absorption.
Aside from funneling huge quantities of rainwater, drainage planes are essential components of the exterior commercial waterproofing system because they also channel vapor downwards and out of the building. Moisture condensation is as difficult to manage as the liquid form of water, because they can seep through any available free space in the building and stay there. Drainage planes vent them out quickly, leaving no time for their dispersion to other areas of the building.
In an exterior commercial waterproofing barrier system, claddings act as drainage planes to protect against water intrusion. Often, drainage planes are installed to create pressure-filled space in cavity walls that prevent outside pressure from driving moisture in.