Open Vs Closed Roof Valley

Repairs to closed valleys are a lot more involved than working on an open valley as is re roofing or making changes to a portion of your roof in the future.

Open vs closed roof valley.

After the self adhering underlayment is installed across the valley a pre bent metal valley lining is installed. To make it easier on you we have included some photos of open and closed valleys in this post so that you can see the difference. It is always a good idea to check with the manufacturer or a certified installer of the product such as ourselves. For a closed valley shingles are installed across the joint where planes intersect.

This metal lining can be made of any type of metal that is resistant to the effects of weather acid rain or other contaminants. Closed valleys are very vulnerable to mechanical damage. We don t normally offer this line although it is available. You are probably wondering what the heck that means.

Closed roof valleys are very popular among homeowners for this reason. When installing a new roof one of the decisions you have to make as a home or building owner is whether or not you want to have open or closed valleys. When compared to a closed valley and open valley adds an additional layer of lining. In comparison to a closed valley an open valley adds another layer of lining into the valley.

This leaves a metal strip or line on the surface of the roof that serves as the valley line. Once the shingles are installed they don t run through the valley area. On a closed valley roof the shingles extend to the valley area completely closing it off. Open valleys can help your roof shed ice and water more efficiently but closed valleys are faster easier and generally cheaper to install.

This valley flashing material can be manufactured from any metal that will resist the effects of weather acid rain and other contaminants. 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. After the underlayment is placed a pre bent metal valley lining is installed. The only type of valley that is unacceptable is the woven valley.

Meanwhile on an open valley roof the metal lining that prevents water from seeping into the underlayers is left exposed. It s all a matter of determining what you re looking for in a roof. 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. With each new course roofing shingles continue up the valley.