What is usually the cause of leaks around flashing?

The cause of leaks around flashing is often linked to improper shingling around the flashing. Flashing is designed to direct water away from critical areas of the roof, such as where the roof meets walls or chimneys. When shingles are not installed correctly around the edges of the flashing, it can create gaps or improper overlaps. These gaps can allow water to penetrate underneath the shingles, leading to leaks.

In the context of roofing, proper installation involves ensuring that shingles properly interlock with the flashing materials. This creates a watertight seal that withstands rain and other environmental stresses. If the shingles are installed without consideration for how they interact with the flashing, or if they are positioned too high or low relative to the flashing, this can compromise the roof's ability to keep water out, resulting in leaks.

Other factors such as weather damage or insufficient sealing materials can contribute to leakage in roofs but are secondary to the critical role that proper shingling plays in conjunction with the flashing. Hence, understanding the importance of correct shingling installation is key to preventing leaks caused by inadequate waterproofing measures around flashing.