Chimney Cracks – Should You Be Concerned?

It’s not uncommon for older chimneys to show a few cracks in their masonry. Newer chimneys also can become cracked through a variety of damaging events. The question is, should you be concerned if you spot a little cracking in your chimney’s bricks and mortar?

The easy answer is yes. The more accurate answer is yes, but let’s determine why the cracks are happening and how extensive they are.

Chimney Repair, Marietta, GATwo types of cracks in chimney masonry

Your chimney’s masonry can become cracked in two primary ways:

  1. Old age: These cracks are gradual and worsen over time.
  2. Extreme weather or seismic events: Unexpected events from earthquakes to lightning strikes can crack a chimney’s masonry, resulting in minor or major damage.


Why you need to repair damaged bricks and mortar

Small chimney cracks likely will lead to bigger chimney cracks. Cracks that start big are an immediate problem. Any time your chimney’s masonry is compromised, water and moisture can infiltrate the openings and begin a cycle of much more extensive damage.

Water is a chimney’s #1 enemy. Once inside open areas in bricks and mortar, it will gradually begin to eat away at the structure. When outside temperatures freeze, the water will freeze and expand, causing more damage.

If left unaddressed, cracks in a chimney can lead to a serious safety issue if the chimney structure begins to tilt to one side or actually collapses.

Common causes of chimney cracks

  • Old age
  • Normal house-settling
  • Improperly built chimney foundation
  • Earthquakes and lightning strikes
  • Water damage
  • Pounding hail storms
  • Gale-force winds

Depending on where you live, your chimney may be more at risk for certain causes of chimney cracks than other causes. Water issues and leaky chimneys are potential problems wherever there is rain or snow.

Chimney Masonry Repair, Marietta, GAHow to address and fix damaged chimneys

Most chimney repair services should be performed by a licensed, certified chimney repair professional. These individuals have the training and the equipment necessary to safely repair your chimney and ensure that the problem is solved. A chimney inspection is usually the first step in getting a chimney properly repaired.



Minor cracks:

If your chimney is showing only minor cracks, a waterproof sealant may be sufficient to prevent more extensive damage down the line.

Crumbling mortar:

If your chimney’s mortar joints are beginning to crumble and if sections of mortar are missing, a process called tuckpointing will add a strong new compound to areas where mortar has fallen away.

Brick spalling:

Loose bricks should not be ignored. Bricks can be replaced and new mortar added before serious damage results.

Large sections of brick damage:

Often seen when a chimney has been neglected for years or following severe weather events, this problem usually calls for partial chimney rebuilding to restore strength to the structure.

Leaning chimney:

If your chimney is leaning, an inspection will be required to determine the cause. It could be because of above-roof structural issues, or it could be due to a problem with the foundation beneath the chimney. A chimney that is leaning may need to be completely rebuilt.

If your chimney is showing any signs of cracking or more extensive damage, you should arrange for a professional chimney inspection by a CSIA-certified technician before using your fireplace again.

Chimney Solutions of Alpharetta, GA, is ready to help with all levels of chimney crack repair, tuckpointing, brick replacement and chimney rebuilding services. Call (770) 771-5501 and get the job done right by qualified Georgia chimney experts.

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