Open Valley Roof Addition

After the underlayment is placed a pre bent metal valley lining is installed.

Open valley roof addition. 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. Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles. Also different architectural styles will use the same type of roof. Stop nailing 6 inches from the center.

To understand what makes a valley either closed or open it is important to understand how a valley is constructed. Roof one side of the valley running the shingles across it. 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. In a previous video we covered how to flash roof edges before shingling.

After installing the rafters we still had to extend the porch roof back over the shed roof creating a valley on either side. In this video we ll flash the valley. 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. But the stakes are higher for valleys than they are for gutters in a previous video we covered how to flash.

That flashing is left exposed so the roof has visible lines of metal running down the valley. First clean the debris out of the valley including sawdust nails and whatever else is in there. Roof valleys are like gutters with a steep pitch. 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. Again choosing the easy way out we opted to build blind valleys aka california valleys where one. Roofing shingles are installed then cut and sealed where they overlap the metal channel. Roof valleys are like gutters with a steep pitch but the stakes are higher for valleys than they are for gutters.

This metal lining can be made of any. Closed valleys or open valleys. The metal is usually pre painted to best complement the shingles color blend. The gable roof on the porch addition was framed with a dropped structural ridge supporting the common rafters above.

Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. When compared to a closed valley and open valley adds an additional layer of lining. Open valley shingle installation.