Open Valley On A Roof

Valleys are typically found where gable dormer roofs meet the main roof or when a house has angled wings or additions where two roof sections in different planes meet.

Open valley on a roof.

Fold the top over the roof ridge and cut the bottom along the drip edge metal. Pros of open valley shingle installation. Roof one side of the valley running the shingles across it. Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing.

That flashing is left exposed so the roof has visible lines of metal running down the valley. When compared to a closed valley and open valley adds an additional layer of lining. Open roof valley this is almost the same as the closed roof valley method except a pre bent metal valley lining is installed instead of a secondary roof underlayment. Stop nailing 6 inches from the center.

This allows water to fall from the higher slope to the lower slope and prevents it from going under the shingles to the roof deck. An open valley relies on metal flashing for protection. Shingles are cut on the higher slope in a straight line through the valley. Shingle the other side of the valley the same way.

Some homeowners do not like the look of open valleys while others feel the metal accentuates the roof s shape particularly if copper or painted flashing is used. Roofing shingles are installed then cut and sealed where they overlap the metal channel. During its installation process the open valley shingle utilizes the w metal flashing which helps in preventing the water from rushing down. Open valley shingle installation makes use of the metal flashing sheets that need to be installed so that they overlap each other by few inches with the upper piece of sheet is resting over the bottom piece.

Once the shingles are installed they don t run through the valley area. The valley area of a roof the straight lines formed when two different planes of the roof meet is a critical area that handles a tremendous amount of water run off. The metal is usually pre painted to best complement the shingles color blend. First clean the debris out of the valley including sawdust nails and whatever else is in there.

This leaves a metal strip or line on the surface of the roof that serves as the valley line.