Important (Behind the Scene) Components[authorbox]
While there is no one “most” important component of any given building envelope system, flashings are certainly critical parts. Whether it be roofing (flat or sloped), exterior cladding (brick, siding, EIFS, etc.) or windows and doors, flashings play a key role in the success of these systems.
Flashings can consist of metal, sheet materials, or even liquid-applied membranes and are typically located at key areas (window/door perimeters, wall transitions, penetrations through roofs or walls, etc.) that would otherwise be prone to leakage. Their primary functions are to keep water away from vulnerable components and/or redirect it away from interior spaces.
The cost of installing proper flashings is a relatively low percentage of an overall system. On the other hand, the effects and costs associated with missing or improper flashings can be extreme.
We regularly encounter the consequences when flashings are not included or are improperly installed. In addition to obvious problems (interior water penetration) rot or corrosion of framing and other concealed building elements can develop and progress unnoticed. Such damage can be extensive and even disturbing.
The accompanying photographs show what can happen when an EIFS assembly lacks flashings to collect and divert water away from internal elements. Repeated and prolonged wetting of the underlying wood components produced the severe damage you see and it went undetected until we opened the system up for inspection.