Chimney Leaks

Chimney flashing itself is typically made of metal like galvanized steel, aluminum or copper. It is generally a piece of metal by itself of in conjunction with other pieces that are bent and installed on the roof between the roof and the chimney. It is used to make a seal at the gap where the chimney comes out of the roof itself. It is the reason why when it rains you don't see water running into your home. It is also typically the spot where most leaks occur for this same reason.

Step flashing gets its name from how the metal installed looks like steps. Each piece of metal is installed into a brick joint and then onto the roof under the shingles. Another type similar is a counter flash. Which looks similar to the step flash but it is made of two separate pieces. One piece laying on the roof, and the second piece over lapping and installed into the mortar joint.

The lap flashing is when the installer runs a solid length of metal the length and width of the chimney. The section that meets the chimney is NOT installed into the brick work but is simply glued or siliconed to the brick itself.

Sometimes leaks at or around the chimney or fireplace can find their origins from the roof and not the chimney at all. They can originate at improperly installed shingles or shingles that have reached the end of their life expectancy.

Vents that come out of the roof can also be a cause of leaks in the home. Other things installed in the roof like sky lights, power vents or attic vents can all be points where water can infiltrate the roof.

In some cases poorly installed roof peak vents can cause a point where water can enter the home. Where uncommon we have seen this as a point of entry.

The step flashing can be repaired in several ways. It can be totally removed and replaced. A con to this though is in most cases the shingles around the chimney will need to be removed and replaced. This could cause a color variation in the shingles around the chimney posing another "visual issue"

The point at which the flashing meets the chimney sometimes pulls out of the joint. New mortar installed here or even some silicone can solve the problem. Also the joint at which the chimney meets the roof can have silicone or roof cement applied to it. This is not a permanent solution but can by time until one canoe made.

The largest reason for chimney leaks is the installation of this type of flashing. The reason being the top of the metal is not secured into the joint and just glued to the side of the chimney. When this silicone or glue gets old it fails and the piece of metal will pull away from the chimney resulting in a leak. These types of flashing are generally installed by contractors who do not know the proper way to install flashing or looking for a quick application.  The repair is the same as in step flashing. Silicone needs replaced at the joints where it meets the chimney and or roof.