In roofing, which type of valley lining exposes the valley linings?

The type of valley lining that exposes the valley linings is the open valley. This design incorporates a visible channel or trough that allows for better water drainage and minimizes the risk of water pooling, which can lead to leaks. In an open valley, the lining material, typically metal, is clearly visible between the shingles, creating a distinct and functional architectural element. This promotes both aesthetic appeal and effective water management in roofing systems.

In contrast, closed valleys and shingled valleys cover the lining with overlapping shingles, which obscures the material underneath. While these options can offer certain aesthetic benefits, they may not provide the same level of drainage efficiency as an open valley. The metal valley is more a description of the material used rather than the visibility aspect, as it can be used in both open and closed valley designs.