Common Roofing Problem: Flashing
Problems with flashing can happen on any type of roof at any facility. Poor or improper installation is a likely culprit. Sheet metal fabrication requires special tools or equipment. Because of this, short cuts are often taken.
Lack of adhesion can be caused by the introduction of moisture behind the flashing that created a blister, or moisture infiltration through the wall, that forces the flashing membrane off the wall. If incompatible materials are used, problems with adhesion are also possible. Building movement because of thermal activity may cause shrinking and flashing membrane to pull away as well. D. C. Taylor Co. estimates that more than 70 percent of roof leaks are a result of flashing problems. Failed flashing increases the risk for high-volume water leaks.
Make sure you hire a licensed roofing contractor that will follow manufacturer recommendations regarding the installation of flashing (e.g. install flashing at a 6- to 8-inch height minimum).
The typical repair method is to remove damaged or faulty flashing and replace it. Situational decision-making is necessary to find the best repair method.