Deflection, Drainage and Drying

Primary and Secondary Water Management Tools for Wall Systems

Deflection. Drainage. Drying. These are the basics of water management. Deflect water wherever possible and ensure any water that is present can drain. It is important to make provisions to dry out the areas that get wet. The techniques are simple, and with Kingspan GreenGuard products and support, the tools are readily available.

Wall cladding, windows, and doors are a structure’s primary weather barrier, deflecting most wind-driven water. However, water will still get through them. Windows and doors leak. Water gets through seams and cracks in wood, vinyl, and fiber cement siding and soaks through reservoir claddings such as brick, stucco, and stone. Plus air passes through siding, carrying water. It is not a matter of if, but when. Where primary deflection fails, water is managed by secondary weather barriers.

Weather-resistive barriers such as building wrap and flashing are secondary water management tools to deflect, drain, and dry water that comes through the cladding. By using a combination of Kingspan GreenGuard flashings, building wraps, and sheathings, water can be deflected, keeping it from further penetrating the wall. Flashings deflect water at vulnerable points around windows and doors. Building wraps deflect water away from sheathing. Kingspan GreenGuard RainDrop 3D Building Wrap is optimally designed with drainage channels that allow water to drain down quickly between the wrap and the exterior cladding, even if the cladding is nailed tightly to the wall. Additionally, every Kingspan GreenGuard building wrap is permeable, meaning it “breathes” to allow moisture vapor to easily escape the wall cavity, facilitating the drying process. These tools are the means of preventing damage from water that passes the primary weather barrier.