Traditional Roof Valley Construction

It is an area where water is directed towards rather than away from therefore correct detailing and construction is essential.

Traditional roof valley construction.

A common misconception is that the mortar bedding is there to prevent water access. Essentially there are three main ways to shingle a roof valley. A closed cut roof valley will have at least four layers of roof materials. Your choice of valley installation method is critical because when improperly installed valleys are risks for serious leaks.

Typically where a valley is located on a roof roof valley replacements are fairly common especially on tiled roofs. Water collects in a valley to flow off the roof. If the roof valley which is going to be put in place is a closed valley then the person who is repairing your roof will place the roofing shingles on top of the roof deck. This is because the old valleys used to be galvanised and they start corroding with time especially if they trap leaves.

One layer each of felt underlayment mineral surfaced roll roofing and two layers of shingles. In order to understand roof valley construction completely you need to know about the difference between an open roof valley and a closed roof. A roof valley is formed where two roof slopes meet. Valleys are typically found where gable dormer roofs meet the main roof or when a house has angled wings or additions where two roof sections in different planes meet.

One of the areas of a pitched roof most prone to leakage if not constructed properly is the valley.