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How to Repair a Brick Chimney

How to Repair a Brick Chimney

Whenever you notice some kind of damage to a brick chimney, you must take some prompt action to repair it. This article is going to help you understand how to repair a brick chimney. Read on...
Bidisha Mukherjee
Chimneys are susceptible to various forms of damage. This is mainly because it is exposed to harsh weather conditions on a regular basis. Repeated water exposure leads to deterioration of the brick and mortar structure. Rainwater seeps into the mortar or brick and gets trapped there. When this trapped water freezes, it expands. This results in chipping and flaking of layers of mortar and brick. If too much water gets into the brick, they may crack. Damage to a brick chimney looks really ugly. Besides, water entering into the chimney through these gaps can cause some damage to its interiors. In that case, you may have to rebuild the chimney.

How to Repair Brick Chimney Mortar

Gear yourself with adequate protective gear like safety goggles and gloves as flying pieces of mortar can cause damage to the eyes and skin. For your convenience, divide the chimney into small sections of one or two feet width and work on each section at a time. To begin with, remove the old and damaged mortar from the first section of the lowermost part of the chimney with the help of a mason's hammer and chisel. Make sure that you remove all the mortar from the areas between the bricks. If some mortar is left behind in some difficult to reach area, then use a scraper to remove them. Then rub a soft bristled brush in all those areas from where mortar has been removed to clear up the mortar dust and debris.

Next, you have to prepare the mortar mix. Read the label of the packaged mortar mix which the manufacturer has provided with suitable guidelines about preparing the mortar and you have to follow the same. You need a mixing container and a hoe for thorough mixing of the mortar. Use a square trowel and a pointed trowel for applying this freshly prepared mortar on each of the brick joints of the chimney surface. Take some mortar on the square trowel and place it just below the joint. Use the pointed trowel to fill up the mortar into the gaps of the brick joint. Once the joint is fully packed with mortar, scrap off the excess mortar that is stuck there with a brick trowel. A jointing tool is then used to compress the applied mortar properly and smoothen up the surface. Finally, when the joint is set, rub off the concrete that gets stuck on the brick surface. Now move up to the next sections and follow the same technique for repairing damaged mortar.

How to Replace a Damaged Brick of a Chimney

When one or two bricks of the chimney are in a badly damaged condition, then you have no other option but to replace them with new ones in order to protect the interiors of the chimney. The damaged brick has to be removed first. Break the brick into smaller pieces with a chisel and hammer and then you can take out the pieces easily. However, be careful and do not apply too much of force as it can damage some adjacent bricks too. Use a wire brush to clean up the cavity that forms after removal of the brick.

Take the broken pieces of the brick to the nearest brickyard as a sample to purchase a new brick whose color, texture, and size matches the old one. Prepare sufficient amount of the mortar mix for installing the brick. Apply a layer of mortar of one inch thickness on the bottom and sides of the cavity where the brick has to be placed. Soak the brick in a bucket of water and then apply a thin layer of mortar on all its sides. Now, with great care, put the brick into the cavity. Tap it lightly with a rubber mallet so that it fits into the gap properly and is in level with other surrounding bricks. Remove all the excess amount of mortar that oozes out. Some areas may require an additional touch of mortar. After that, use the jointing tool to give a finishing touch to the brick joints. Let the mortar dry up a bit and brush off loosely bound traces of mortar with a stiff bristled brush. Sprinkle little water from time to time so that the mortar does not crack.

The repair job is not that difficult provided you use the right tools and technique. However, if you find that more than two bricks of the chimney are damaged, then do not hesitate to take help from professionals.