Why Your Chimney Is Leaning and What to Do About It
Aside from a major chimney fire, a chimney that leans or tilts to one side is one of the most serious events a homeowner can face. When your chimney is leaning, there’s a reason for it, and that reason often involves the foundation beneath the chimney and/or the soil beneath the foundation.
How to spot a leaning chimney
The first sign that your chimney is tilting to the side is the fact that you can see it with your eyes. But chimneys are tall structures, and it’s common for there to be a problem and some initial stages of leaning without easily being able to detect it.
Tilting chimneys often leave clues including:
- Dislodged flashing that has opened a gap between the chimney masonry and the roof
- Gaps between the exterior lower half of the chimney and the home’s siding/walls
- The same gaps as noted above but filled in with caulking or some other material by the previous owner (tells you the problem isn’t new)
- Loose chimney bricks, cracked mortar joints or crumbling near the chimney on the roof or even down into the yard
- A leaky chimney
If you spot any of these signs, you should bring in professional help to evaluate the extent of the problem and determine the correct way to repair it.
Possible causes of a tilting chimney
Chimney inspectors and building contractors have identified a variety of reasons why a chimney tilts to one side. Common causes are:
Footing that’s too small: For stability, the slab below the chimney should extend at least six inches beyond all sides of the chimney base. If the footing is too shallow, freezing of the ground below it can cause shifting as moisture in the ground expands and contracts.
Problems with the soil: If soil below the footing is too loose, the chimney won’t be securely supported – this is a very common cause of leaning chimneys.
Cracks in the footing: Poor-quality concrete is more prone to crack than a higher-grade material. Cracking allows water into the openings, which will cause further damage and instability.
Problems with reinforcement: If the chimney footing hasn’t been properly reinforced (rebar) or if the rebar wasn’t installed correctly, cracking and shifting likely will occur over time.
No footing: Some older homes may have no footing at the base of the chimney. This makes it far more likely for the structure to begin to tilt.
House/foundation settling: Both houses and their foundations settle over time. This can cause a chimney to lean.
What to do if your chimney is leaning
If you have spotted signs that your chimney is leaning to one side, your first step should be to contact a local certified chimney repair services company or a firm engaged in foundation work. A thorough inspection will be required to learn the extent of internal and external damage to the chimney and home and to decide on the best method for resolving the problem.
Chimney Solutions of Alpharetta, GA, can help with many chimney problems. We provide CSIA-certified chimney inspections, chimney repair, chimney rebuilding and complete chimney sweep services. When you have a problem with your chimney, call the problem-solvers at (770) 255-1300.