Open Valley Roof Addition

Stop nailing 6 inches from the center.

Open valley roof addition.

Closed valleys or open valleys. After installing the rafters we still had to extend the porch roof back over the shed roof creating a valley on either side. Shingle the other side of the valley the same way. But the stakes are higher for valleys than they are for gutters in a previous video we covered how to flash.

To understand what makes a valley either closed or open it is important to understand how a valley is constructed. An open valley relies on metal flashing for protection. For an open valley a sheet of metal usually steel sometimes copper is fastened to the roof deck. The gable roof on the porch addition was framed with a dropped structural ridge supporting the common rafters above.

In this video we ll flash the valley. There are two common methods for completing the flashing of a valley in a shingle roof system. Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Roofing shingles are installed then cut and sealed where they overlap the metal channel.

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. Roof valleys are like gutters with a steep pitch but the stakes are higher for valleys than they are for gutters. Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles. Intricate roofs have many parts that incorporate several of the basic roof designs such as a gable roof sitting atop a gambrel or variations of the gable valley roof design using one or a variety of different types of roof trusses also see our very detailed diagrams showing the different parts of a roof truss.

This metal lining can be made of any. Roof one side of the valley running the shingles across it. First clean the debris out of the valley including sawdust nails and whatever else is in there. Open valley shingle installation.

After the underlayment is placed a pre bent metal valley lining is installed. 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. In a previous video we covered how to flash roof edges before shingling. One of the details that varies between homes is the method of flashing the valley areas of the roof.

Roof valleys are like gutters with a steep pitch. The metal is usually pre painted to best complement the shingles color blend. Again choosing the easy way out we opted to build blind valleys aka california valleys where one.