It is always a good idea to check with the manufacturer or a certified installer of the product such as ourselves.
Open or closed valley roof.
Closed valleys are very vulnerable to mechanical damage.
Your choice of valley installation method is critical because when improperly installed valleys are risks for serious leaks.
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.
Essentially there are three main ways to shingle a roof valley.
A roof valley is formed where two roof slopes meet.
Meanwhile on an open valley roof the metal lining that prevents water from seeping into the underlayers is left exposed.
An open valley has a gap usually about 6 inches between the tile or shingles at the valley area.
On a closed valley roof the shingles extend to the valley area completely closing it off.
Closed valleys may have a tendency if not constructed properly to channel water under the shingles laid over the bottom layer of shingles.
Water collects in a valley to flow off the roof.
The only type of valley that is unacceptable is the woven valley.
And while some homeowners may prefer the aesthetics of a closed valley the heavier and thicker the shingle the less likely it is to lie flat across a joint.
If you prefer a concealed valley lining and want your roof to blend together choose the closed valley.
If you like exposed metal especially if you use copper you may want to pick open.
The open valley looks like each plane of the roof was cut in separate and the eye is drawn to the separation.
Roofing material manufactures or roofing associations may have recommended installation guidelines for their products or for various roofing materials.
When it comes to aesthetics that is all up to preference.
A closed valley is where the tiles or shingles are butted up against each other in the center of the valley.
The metal is usually pre painted to best complement the shingles color blend.
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.
For an open valley a sheet of metal usually steel sometimes copper is fastened to the roof deck.
Open valley roofs what s the difference between a closed and open valley roof.
Although the open valley is recommended by the manufacturer closed valley is acceptable.
This roof is on a small cabin in the back of beyond and the only valleys will be on 3 small dormers with about 6 feet of valley per side so i m not sure the water will wear out the valley shingles argument will work.
However open valleys may be susceptible to water back up along the top of the cut off shingles in the valley if not properly trimmed potentially causing roof leaks.
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.
