A drainage wall system is a construction method designed to manage moisture behind the exterior cladding of a building.
Understanding Drainage Wall Systems
Based on the provided information, a drainage wall system is going to be a system in which there's an exterior cladding behind which there will be some form of the drainage plane made up of different construction components. The specific components needed can vary depending on the requirements of the building's location and climate.
This system is crucial for preventing water from penetrating the wall assembly and causing damage like rot, mold, or structural issues. Instead of trying to create a perfectly sealed wall, a drainage wall system acknowledges that some water will inevitably get past the exterior layer and provides a pathway for it to drain away harmlessly.
Key Components
The core elements of a drainage wall system, as described, are:
- Exterior Cladding: This is the outermost layer of the wall (e.g., siding, brick, stucco). While it provides the primary weather protection, it's understood that some water can bypass it.
- Drainage Plane: Located behind the cladding, this is the critical layer that channels water downwards. It is composed of "different construction components."
Here's a simplified view:
| Component | Location | Function |
|---|---|---|
| Exterior Cladding | Outermost layer | Primary weather barrier |
| Drainage Plane | Behind the Exterior Cladding | Channels moisture downwards and outwards |
The "different construction components" making up the drainage plane can include materials like:
- Water-resistive barriers (WRBs), often called house wrap
- Drainage mats or rainscreen components that create a gap
- Flashings at windows, doors, and transitions
How it Works
In essence, when wind-driven rain or moisture penetrates the exterior cladding, it encounters the drainage plane. This plane directs the water down through a drainage space (if present) or along the surface of the WRB, allowing it to exit the wall assembly, typically at the base. This prevents water from soaking into the structural sheathing or insulation layers, preserving the integrity and health of the wall.
Using a drainage wall system is a best practice in modern construction, especially in areas prone to rain or moisture challenges, as it significantly enhances the wall's durability and reduces the risk of moisture-related problems.
