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How do I repair a Chimney Leak?

You may start to notice the sound of dripping water coming from your chimney, moisture on the walls, a musty smell after rain or notice condensation inside the firebox. These are just some of the symptoms behind a chimney leak. The way that you repair the leak, will depend on what the reason behind it is. Here are the top four reasons as to why your chimney may be leaking and tips on how to fix it:

Chimney Crown Cracks

Your chimney may be leaking because of cracks in the chimney crown. In the winter when the rain starts to freeze on the chimney, as the sun comes out it will create a crack that will eventually get bigger. It’s good to get this sorted before it gets too big by inserting a crown coating material. If it has started to get worse, however, you will have to relay and remove the masonry. This will have to be done professionally.

Leaks caused by condensation

Condensation is a problem faced by many homes worldwide. But the reason behind it can be because of moisture from gas fumes in the wood fireplace. A good fix to the condensation is installing a chimney liner that will vent the chimney properly, insulating wood stoves and fireplaces.

Leaks caused by leaking bricks

Leaking bricks can occur because of water penetration through the masonry and mortar joints. To fix this, you will have to remove the damaged pieces, before replacing them with new bricks and mortar using a caulking gun. It then needs to be waterproofed to make sure that it is protected from future leaks.

Chimney flashing leaks

The flashing on your chimney is supposed to keep the water away from the chimney. Over the years it starts to get worn, therefore may need to be replaced if a leak starts to occur. In order to fix it, you will need to remove the roofing cement, before applying a new coat behind the flashing (which may also need to be replaced). Use masonry screw or nails to reattach the flashing to the chimney. Make sure that the joint between the brick and the flashing is secure and that the exposed nail heads are covered.

Find more Chimney resources here on Blakes Chimney Sweeping Blog Page.

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