Sometimes, roofing plugs can corrode, leaving small holes in the material. To fix these holes, a roofer will first scrape the edges around the holes so that the patch can easily adhere. Then, they will place a patch of gasket material over the hole and secure it with roofing cement. Metal gaskets are commonly used to seal water around chimneys, ventilation pipes, valleys where two slanted roofs meet, and sometimes above exposed windows. To ensure that your joint cover is properly sealed and prevent leakage, it is important to inspect it every spring.
If you notice thin spots or gaps along a gasket joint, spread roofing cement over the entire joint and apply it generously with a trowel. Make sure that the joint cover edge is completely covered.
