Roof Valley Leak

The resulting cut is very similar to the angle you might see on the tip of a wood chisel.

Roof valley leak.

A flashing is a transitional roofing material that connects the roof material to some other building material or to another part of the roof. When a shingle from either roof intersects and passes over the metal valley flashing it needs to be cut at an angle. The most common cause of a roof leak where metal flashings are used is shingles that have been improperly cut. Most shingle installers will use a thick 30 lb paper as a base for the valley.

The reason why the roof valley is such a sensitive area has to do with all the rainwater and or melting snow that accumulates and flows through the valley on its way into the gutters. And damaged flashing is behind most roof leaks. Just like in nature a valley on a roof is designed to collect water. Valley areas are prone to leak due to the lack of using proper materials.

You know the roof is bad if shingles are missing or obviously damaged or when water stains the ceiling or walls. A roof valley is very prone to leaks especially if you have an older roof. The goal is to find the leak before the entire roof goes bad. They are common on both hip and gable roofs.

Roof valleys carry a lot of water. Finding the actual spot where the roof leaks is difficult because water can enter the roof in one place and run down to another before it starts soaking into the ceiling. Many roof valley leaks are caused by roofing nails that have been poorly placed and are acting as a dripper feeding water through from the roof above. Most roofers that install shingles will not have rubber membranes with them to do such areas.

If that water doesn t shed off the roof fast enough or gets under the roofing material roof leaks will soon develop. When a valley begins to leak it s very difficult to surgically address the leak. And roof leaks in valleys often turn into unsightly repairs. Valleys can be especially troublesome because they carry a lot of water during heavy rain.

In either situation the leaking roof valley can be fixed by removing affected shingles and structural elements and upgrading your roof s flashing. Roof valley leaks valleys in your roof are locations where two roof planes intersect and form a v shaped valley that runs down a slope of your roof.