Open Closed Valley Roof

Once the shingles are installed they don t run through the valley area.

Open closed valley roof.

The only type of valley that is unacceptable is the woven valley. This leaves a metal strip or line on the surface of the roof that serves as the valley line. The closed variation is a flashing that has been completely covered with shingles while in the open variation will have the flashing completely exposed to the elements. An open roof valley meanwhile is a flashing method in which a sheet of pre bent metal is installed after the valley lining is placed.

Water collects in a valley to flow off the roof. Since the area is covered by shingles the closed valley makes the roofing system more appealing when seen from the ground. The metal is usually pre painted to best complement the shingles color blend. The roofers apply the shingles cutting and sealing the ones that overlap the metal.

The self adhering section acts as the lining for the valley. This valley flashing material can be manufactured from any metal that will resist the effects of weather acid rain and other contaminants. It is always a good idea to check with the manufacturer or a certified installer of the product such as ourselves. If you have a shingled roof as most torontonians with a sloped roof tend to have then you will have one of two kinds of valleys on your home.

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. Part of the underlayment includes a self adhering ice and water shield that a heavier gauge than the rest of the underlayment. Although the open valley is recommended by the manufacturer closed valley is acceptable. Woven closed cut and open.

After the self adhering underlayment is installed across the valley a pre bent metal valley lining is installed. For an open valley a sheet of metal usually steel sometimes copper is fastened to the roof deck. Roofing shingles are installed then cut and sealed where they overlap the metal channel. A closed valley is where the tiles or shingles are butted up against each other in the center of the valley.

In comparison to a closed valley an open valley adds another layer of lining into the valley. Your choice of valley installation method is critical because when improperly installed valleys are risks for serious leaks. About open roof valleys. Essentially there are three main ways to shingle a roof valley.