The wall system opening often refers to which type of flashing?

The term "wall system opening" typically pertains to areas around windows, doors, or other penetrations in a wall assembly where there is a need for effective moisture management. Wall termination flashing is specifically designed to direct water away from these openings. It is installed at the junctions where the wall meets the roof, and above windows and doors, to prevent water from seeping behind the wall materials and causing damage.

In comparison, through wall flashing is primarily used for masonry walls to prevent moisture from penetrating through the wall assembly. Header flashing is installed above windows and doors to divert water around these openings, while Z flashing serves a similar purpose but is typically used for horizontal lap siding or metal shingles. While all types of flashing play important roles in moisture management, wall termination flashing is the most relevant for addressing the specific concerns associated with wall system openings, ensuring proper drainage and protection against water intrusion.