A piece of metal flashing or a structural steel member formed with two parallel flanges connected by a perpendicular web, creating a Z-shaped cross-section. In framing and masonry, it serves as a drip edge over windows and doors to direct water away from the wall cavity. In heavy steelwork, larger Z-bar profiles act as purlins or girts to support roof and wall cladding.
Run a strip of Z-bar over that window header before you install the siding so water doesn't get trapped.
Also heard as
- Z-flashing
- Z-purlin
Related terms
Drip edge
A metal flashing installed at roof perimeters to direct water away from the fascia and underlying wood.
Step flashing
Overlapping L-shaped metal pieces used to seal the joint where a sloped roof meets a vertical wall.
Cladding
The non-loadbearing exterior skin applied to a building to shed water and provide aesthetic appeal.