What are the Building Envelope Control Layers?
Table of Contents
Building Enclosure Control Layers?
What are the building envelope control layers? As discussed in our previous post, the building enclosure separates the interior environment from the exterior. Specific control layers must be present to perform this function properly. Before referring to the layers, we will therefore first look at the enclosure functions.
What are the functions of the building enclosure (building envelope)?
As noted by Straube (2012), there are several functions associated with the enclosure. Of particular interest to our conversation are the support and the control functions since these are critical to the enclosure’s performance.
The support function generally refers to the structural integrity of the assembly. Since there is not much controversy (relevant to our current conversation) about the structure required for the exterior wall, we will not pay much attention to this for now.
We, therefore, turn our attention to the control functions related to the control of:
- Water (liquid), e.g., rain
- Water vapor
- Air
- Heat
- Fire
- Smoke
- Sound
- Light
- Insects
- Particulates
- Access
What are the most critical envelope functions for Enclosurists?
While all 11 of these functions are essential to the successful functioning of an enclosure, the four most essential control functions (and therefore the building envelope control layers) are in order of importance the:
- Water control layer
- Air control layer
- Vapor control layer
- Thermal control layer
When reviewing or designing the building enclosure, be sure to focus on the continuity of these layers and the interactions between them. In a future post, we will discuss each layer’s required characteristics and the relationship between the various layers.
References, Credits and Further Reading (Includes Affiliate Links)
Straube, J., 2012. High Performance Enclosures. Design Guide for Institutional, Commercial, and Industrial Buildings in Cold Climates. Building Science Press, Somerville, MA.
BSI-001: The Perfect Wall by Joe Lstiburek (https://www.buildingscience.com/documents/insights/bsi-001-the-perfect-wall)
