Don’t Ignore These Common Signs of Chimney Damage!

Workman repairing a chimney stack on top of a roof.

Your chimney is an important part of your home and fireplace. If it can’t function correctly, your safety is at risk. Some of the signs of chimney damage may appear to be benign wear-and-tear to the untrained eye. A damaged chimney can lead to moisture problems, chimney fires and even the possibility of carbon monoxide poisoning! Keep an eye out for these common signs of chimney damage.

Most Common Signs of Chimney Damage


Have you ever seen an unusual white stain across the brick of a chimney? Otherwise known as efflorescence, it’s a sure sign of excessive moisture in the masonry. Whether due to leaks or other damage, if you spot efflorescence, don’t wait to get a chimney inspection! Moisture and mold can quickly deteriorate your chimney and lead to other, more dangerous problems. The more moisture in your area, the more likely you are to experience these types of problems! Living around the Great Lakes region, we see leaky chimneys and mold in many chimneys from Toledo, Ohio all the way to Metro Detroit.

Cracked or Deteriorated Mortar Joints

Mortar joints in your masonry can happen for a variety of reasons. Even when maintained perfectly, they will deteriorate over time from weather and wear. If you see space between bricks or any other obvious cracking, it needs to be repaired immediately.

Damaged mortar joints greatly increase the amount of moisture that leaks into your chimney. During the colder months, this moisture can freeze, expand and cause further damage. These cracks allow smoke and heat to escape the chimney in places they shouldn’t. However, the most serious risk is the increased chance of collapse when the bricks lose their stabilizing mortar.

Sometimes the mortar joints are visible on the exterior of the chimney. Other times, the damage is on the interior and can be seen in the firebox. For any other damage, you would need a professional chimney inspection using a video camera.

Spalling Bricks

Bricks are porous. Over time, moisture can penetrate brick masonry and begin to break it apart. This is known as spalling. Like mortar joint damage, this can be exacerbated in cold weather climates when moisture freezes in the bricks.

There are a few common causes of spalling:

  • Using a high-powered pressure washer when cleaning the masonry
  • Weather, particularly in extreme weather climates
  • Aging brick in old homes
  • Low-quality components, often used in newer pre-fabricated homes

As age plays a big role in spalling, it’s impossible to completely prevent. However, if you pay close attention and use a masonry sealant, you can minimize its effects.

Cracked or Melted Crown

A chimney crown is essential to protect your chimney from external damage. Rain, snow and animals will all invade your chimney if it’s not guarded with a crown. Even a small breach can lead to major chimney damage.

That means any visible damage to your chimney crown should be repaired. For smaller cracks that happen due to weathering, you can simply reseal them. However, if you notice bigger cracks or crumbling masonry, the crown may need to be replaced.

Shaling Flue Tiles

Inside your chimney is a flue liner that protects the brick and your home from heat, while helping to direct the flow of air up and out of your home. A damaged flue liner is no joke. If you start to see thin slices of the tile from your liner in your firebox, you have a shaling problem.

Fortunately, you have an obvious sign of damage. Many chimney liner problems are hard to detect for the average homeowner, due to the liner running the entire length of the chimney. If you notice shaling tile, call your local CSIA-certified chimney sweep for an inspection right away.

Deteriorated Flashing

Chimney flashing is a sheet of metal that adds a watertight seal to the connection between your chimney and roof. Water leaking into your roof can cause wood rot, mold and a host of other problems. Flashing isn’t immune to weathering and over time it will need replaced.

If you find rust, holes, or areas where the seal between the flashing and the roof have worn, you’re at risk for water damage. Corners are particularly vulnerable to wearing away, so keep a close eye on your flashing. It may be possible to repair small damage to flashing, but it’s often better to replace it. Compromised flashing will lead to water reaching parts of your home that you won’t notice until major damage is done.

Wallpaper & Paint Damage Near Your Chimney

Have you ever noticed wallpaper or paint peeling near your chimney? This is a clear sign that something is wrong. The brick or mortar on the interior could have chipped or cracked, or your flue liner may be damaged. In some cases, homeowners that installed gas fireplaces neglected to install properly sized flue liners. We frequently replace chimney liners in Michigan homes due to their extended use in the cold winters. If you can't remember the last time you had your chimney liner inspected, it's likely at risk.

If you notice peeling wallpaper or paint, or paint that appears to bubble near your chimney, schedule a chimney inspection as soon as possible!

Can a Chimney Be Damaged Beyond Repair?

Yes! Unfortunately, in some cases, a chimney in such disrepair that it becomes a structural hazard, it needs to be replaced entirely. While most homeowners catch problems before they get this bad, it can happen.

The best way to avoid needing your chimney replaced is to continue scheduling annual chimney inspections and repairing any issues as they appear.

What services are included in your annual chimney cleaning? Info Graphic

Don’t Ignore a Damaged Chimney! Call Doctor Flue!

If you think your fireplace or chimney needs repairs, contact us today! Doctor Flue offers chimney services in Michigan and Ohio and can inspect your chimney and identify any potential risks. We’ll get you set up right away so you can have peace of mind.

Call Us: 1-800-438-3583

Email Us:

Office Hours: Mon-Fri: 8am-4pm

Contact Us | Request A Quote


Connect with Doctor Flue on Social Media

Facebook | Twitter | Google +

This entry was posted in Common Fireplace & Chimney Problems, Tips & Safety and tagged , , . Bookmark the permalink. Follow any comments here with the RSS feed for this post. Both comments and trackbacks are currently closed.