In comparison to a closed valley an open valley adds another layer of lining into the valley.
Open vs closed valley roof.
A closed valley is where the tiles or shingles are butted up against each other in the center of the valley.
Open valleys and closed valleys.
After the self adhering underlayment is installed across the valley a pre bent metal valley lining is installed.
Furthermore the description of the roofing company whose closed valley failed seemed to fit the profile of a fly by night roofing company and so i d have to assume that workmanship and expertise was secondary to making a quick buck.
For a closed valley shingles are installed across the joint where planes intersect.
Because of the sheer amount of water being navigated through this section your valleys need to be properly sealed.
Moving on here are a couple of things to think about when deciding open or closed.
Valleys are created where two roof slopes meet.
With each new course roofing shingles continue up the valley.
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.
Find out the differences before you talk to a roofing expert.
There are two methods for sealing valleys.
According to long time iko sales representative jeff tessaro closed valleys for residential construction have been popular since he was a roofing contractor in the late 90 s.