Over Valley Roof

Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing.

Over valley roof.

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. Valleys are created where two roof slopes meet. All of the shingle rows will need to be lined up correctly. Water collects in a valley to flow off the roof.

Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Cut bottom of flashing so the entire width of the valley flashing extends approximately 1 2 to 3 4 over the fascia trim board along eaves the following photos illustrate removal and replacement of a closed cut valley with new open metal valley. Fold the top over the roof ridge and cut the bottom along the drip edge metal. Roof valleys are troughs that discard runoff water where two sections of sloped roof meet.

Because of the sheer amount of water being navigated through this section your valleys need to be properly sealed. Your choice of valley installation method is critical because when improperly installed valleys are risks for serious leaks. On jul 10 2010 a woven valley shingle installation is one where the shingles from both sides of the roof valley extend over the valley and weave together overlapping courses alternately. There are two methods for sealing valleys.

Shingle the other side of the valley the same way. Stop nailing 6 inches from the center. Woven closed cut and open. Extend entire width of flashing completely to the bottom of the roof valley.

Overlap metal roof valley sections by 12 inches and seal the lap with a flexible sealant such as polyurethane or butyl on roofs shallower than 5 12. 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. Essentially there are three main ways to shingle a roof valley. Pros of woven valley shingle installations.

Open valleys and closed valleys. With a clean valley you can lay down some peel and stick roofing membrane. A roof valley is formed where two roof slopes meet. Where two roof valleys meet for example above a gable dormer a soldered joint is likely to break from the movement.