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Can You Repair a Chimney By Yourself?

The chimney takes a lot of beating from smoke, heat, and ruthless weather elements. It is therefore obvious that even the most durable chimney like a brick chimney will at some point exhibit signs of some sort of damage. Some of the signs of a chimney in need of a repair include hairline cracks, damaged chimney cap, broken bricks, cracks around the large crown area, and a leaning chimney. If these issues are not addressed in time, chances of chimney fires are very high. Although it may sound like rocket science, repairing a damaged chimney is not that hard. If you are a handy person, you can do it by yourself using this easy and simple chimney repair guide.

  • Patch Cracks in the Large Crown Area
Close-up detail of new built brick plastered chimneys on house top with metal tile roof

The larger crown, being a little flat and on the topmost part of the chimney, is very susceptible to weather elements and cracks are a common problem. The most probable cause of cracks on the larger crown is expansion and contraction when the chimney is being used and when it is not in use. The worst-case scenario is when ice, hail, or twigs set in the cracks and cause further expansion of the cracks. To repair such cracks use, a squeeze bottle to put pre-mixed cement or mortar into the cracks, and then use a putty knife to force it in.

  • Replaced Broken Bricks

If there are severely damaged bricks, they should be replaced with new ones. To do this, use a drill to bore holes into the mortar. Then use cold chisel and hammer to chip out the loosened mortar to the back. Carefully remove the broken brick, and use the chisel to remove the remaining mortar from the surrounding bricks. Use a trowel to butter the surroundings with new mortar and carefully put the new brick into the place of the old one. Then remove the excess mortar and smoothen the surface.

  • Repoint the Mortar

Loose mortar is not just unsightly, it can also cause weaknesses amongst bricks and eventually the whole chimney masonry may come crumbling down if something is not done on time. Use the cold chisel and hammer to remove the loose mortar from the joints, until you reach the intact mortar. Use a wire brush to clean all the remaining bits of mortar from the joints because putting new mortar on top of old loose mortar will only make it even looser. Spray the clean joints and wait for a few minutes before applying the new mortar by the use of a trowel tool. Then use the tuck-pointing tool to smoothen down the mortar until the joints resemble the intact ones.

  • Patch Hairline Cracks

Just like the name suggests, hairline cracks are small in size of a hairline. However, as small as they may be, it does not mean that they should be ignored. This is because if water or solid material happens to get into these cracks and expand, the cracks may expand into bigger cracks that may lead to structural damage of the whole chimney. To patch the cracks, use a wire brush to remove dirt from the cracks. Then use a putty knife to scrape away debris around the cracks then use a brush to apply undiluted water repellant. Use a piece of cloth to wipe away the excess repellant around the hairline cracks.

  • Caulk Around the Flue and the Crown

Broken caulk at the gap between the crown and the flue is a major loophole for water to seep in and flow down the flue to the fireplace. It should, therefore, be patched as soon as you notice the slightest wear and tear around this area. Use a wire brush to clean and remove moss and the loosened mortar, then use a caulk gun to spray hot mortar around the area. As you do this, ensure to snip the nozzle of the caulk gun against the gap, to ensure that mortar lays intact but do not overdo it.

If you are not a very handy person, then do not try repairing yourself. If you are not sure of what you are doing, you might end up causing further damage to the chimney. Instead, call in a contractor to do the work for you. On top of doing a great job, a contractor will offer professional advice on what should be done to prevent damage in the future and the best way to approach them. Landing an experienced and great contractor can help a great deal.