24.1 Understanding and Inspecting Flashing

In the illustrations of this section, there are some typical yet very important flashing details provided as general guidelines for correct installation techniques. They are not presented as the only solutions to flashing — because there are certainly many other viable solutions — but as examples of workable approaches for protecting shell penetrations from water intrusion.

Window flashing and deck-ledger flashing are essential for preventing water damage to wall assemblies. A kick-out flashing is important to protect against water intrusion. A variety of manufactured windowsill and door threshold flashing components (such as pre-molded pan flashings) are also available in lieu of site-built flashing components. These components are used to expel any water leakage at the base of windows and doors.

The illustration shows window flashing details that can be used depending on when windows are installed related to the envelope’s weather barrier (housewrap or building paper).

In the next illustration, the flashing details at the jamb and the sill are designed to provide protection against water intrusion in more severe weather conditions.

This is an illustration of a flashing practice at a deck attachment to a house’s exterior wall.

This illustration shows flashing details at a brick veneer wall.