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The Top Reasons Why Chimneys Leak

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When your chimney has a leak, rain can cause water to enter through the chimney and can cause damage in other areas of your home. Before you can have your roof repaired, it is helpful to try to determine what is causing the leak in the first place so that the chimney repair contractor does not have to spend as much time diagnosing it. Below are a few common leak causes that you can check for. 

Incorrectly Installed Flashing

Chimney leaks are caused by a variety of problems, including a flashing that isn't correctly installed. If this is the case, you should contact a chimney repair specialist who can correct these mistakes.

Flashing That Is Rusted

Another cause of a chimney leak is a rusted flashing. The flashing is usually made out of aluminum, which is resistant to rust. However, if it is made out of another material, such as steel, it is more likely to rust. If the flashing becomes cracked or torn, it will not be able to prevent water from traveling down the chimney and roof. A short-term solution is to apply waterproof tar. However, the tar will wear away quickly. There are also specialty sealing products that can seal the opening for longer.

Defective Sheet Metal Caps Or No Cover At All

The sheet metal chimney cap might have a defect. This problem should be corrected by a sheet metal contractor and should never be repaired by an amateur. If your chimney does not have a cover, rainwater will obviously fall directly into the chimney. A chimney cover is a good idea not only because it will prevent water from entering, but will also stop birds and small mammals. If debris enters the chimney, this will prevent smoke from escaping and can cause the home to fill with smoke.

Defects In A Mud Cap

The leak might be caused by a defect in the mud cap. Cracked mortar can allow for rainwater to enter the fireplace. Symptoms of this will include water in the hearth or somewhere else in the home, depending on whether there are other impediments in the fireplace. The mud cap will need to be replaced and a flue cap should be inserted.

Cracked Mortar

The mortar in-between the bricks, which holds the chimney together, can begin to crack. Even with a chimney cover, water can enter much more easily. Besides cracks, worn down mortar can allow moisture to become absorbed into the chimney, which can later cause humidity problems for other areas of the home.

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