Western Cut Roof Valley

Roofing shingles are installed then cut and sealed where they overlap the metal channel.

Western cut roof valley.

Provided the rest of the roofing shingles were properly installed and are performing properly my experience has been that an open valley system holds up better over time tessaro says. The top joinery of both valleys when they meet on the same plane of roof is shown here. Further they wear out faster than a metal valley. A chalk line is then used to strike a line from the top of the valley to the bottom of the valley.

Alternatives for the closed cut valley installation are the woven metal open cut and long island installation. Cut each side at the upper end of the valley to conform with the corresponding slopes of the roof. I have my valley custom made with water trough to help with leaking b. In summary during the installation of a closed cut valley you install the first roof plane s shingles into the valley.

With an open valley a strip of metal will be visible on the roof wherever two opposing roof planes meet. This might lead to annoying leaks in heavy rains or at the very least a damaged roof underlayment. The shingles are then cut out of the valley area opening the surface of the valley lining to water run off and the environment. It is essential to only use whole not cut shingles during this step.