CONTROL LAYERS
There are (4) primary Control Layers that play critical roles in the performance of exterior envelope design.
There are (4) primary Control Layers that play critical roles in the performance of exterior envelope design.
THERMAL
AIR
WATER
VAPOR
There are some products that can do the job of multiple Control Layers, but it is important to understand what each layer is doing, and how the building's location and HVAC design might have affect them before specifying or detailing anything. We call them "control layers" instead of barriers, retarders, membranes, etc to avoid confusing terms related to the physical properties of each layer (i.e. a vapor control layer can be both a vapor barrier, or a vapor retarder).
In order for the control layers to be effective, they need to be continuous around the entire building envelope - in plan and section. A breach in any of the layers will compromise it's performance and the performance of the assembly in which is was used.
In order for the control layers to be effective, they need to be continuous around the entire building envelope - in plan and section. A breach in any of the layers will compromise it's performance and the performance of the assembly in which is was used.