Flat Valley Roof

Because of the volume of water and lower slope along valley lines valleys are particularly vulnerable to leakage.

Flat valley roof.

Your choice of valley installation method is critical because when improperly installed valleys are risks for serious leaks. Valleys are a prime leak area so it s important to be careful. A roof valley is formed where two roof slopes meet. A roofer must be careful where the nails are placed in the shingles of valley roofs.

Valley areas are prone to leak due to the lack of using proper materials. We love the flexibility of a flat roof for certain design limitations but they have a bit of reputation for leaks and repairs. Building a flat roof valley is no different than a plumber installing a drainpipe that is flat for a few feet just to accommodate some aesthetic feature. A valley roof leak is the most common type of roof leak.

This is a granulated roll installed in three feet sheets it is mostly used on commercial flat roofs and is well adapted for residential application especially dead valleys or other troublesome spots. Repairing a dead valley isn t really a diy project for most homeowners. Most roofers that do shingles will use a heavy base paper instead of a rubber membrane. These leaks can be caused by poor roofing practices or just simply by the age of the shingles on the roof.

Water like to follow the valley to the edge and flow back under the valley. When a valley is flat like this one in the image it is more problematic. Of course flat roofs are not flat but have a very slight roof pitch of between 1 4 to 1 2 per foot. Despite this flat roof valleys should never be built.

Water collects in a valley to flow off the roof. The open woven and closed cut methods are demonstrated. Just enough slope to drain water but also flat enough to be a problem if not constructed properly. Gaf mastering the roof chapter 12 this video demonstrates the proper installation technique for installing roofing valleys.

There are two basic types of valleys. Valleys are created where two roof slopes meet. Intricate roofs have many parts that incorporate several of the basic roof designs such as a gable roof sitting atop a gambrel or variations of the gable valley roof design using one or a variety of different types of roof trusses also see our very detailed diagrams showing the different parts of a roof truss. The roof design is as essential to the proper function of a house as is the foundation plumbing or electrical design.

Essentially there are three main ways to shingle a roof valley. Also different architectural styles will use the same type of roof. If the nails are placed in the very center of the valley leakage will occur.