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What to Do When Crumbling Bricks Are Spotted

It’s happened to a number of homeowners just like you- after a few years of neglecting your chimney, you look up one day to see its bricks crumbling and cracking and then notice broken pieces on the ground. If this scenario has happened to you and you are at a loss on how to deal with it, don’t worry. Here is what to do when crumbling bricks are spotted in your chimney.damaged chimney bricks in Spring Green WI

Spalling Bricks are Crumbling Bricks

The term for crumbling bricks in your chimney is “spalling.” What is spalling? It’s quite simple: spalling is a phenomenon that occurs when bricks are baked by the sun and become more porous as a result. Pours bricks act like a sponge and absorb moisture, which will expand and contract during the freeze-thaw cycle. Repeated expansion and contraction over time will cause the bricks in your chimney to break down.

Aside from the cracks in your chimney cracking and breaking, a telltale sign of spalling is known as Efflorescence, which is a white powder on the exterior bricks in your chimney. 

Of course, there are other causes of crumbling bricks in your chimney; here are a few more common causes-

  • Shifting ground.
  • Lightning Strikes
  • Earthquakes
  • Strong Storms

Regardless of the cause of your chimney’s crumbling bricks, If you see broken bricks or spalling, you need to contact a qualified chimney sweep service immediately to inspect and repair your chimney before it collapses. 

What to Do When Broken Bricks or Spalling Occurs

As previously mentioned, contacting a qualified, reputable, and certified chimney sweep service is the first step to dealing with a crumbling chimney. Here is how the chimney sweep service will deal with your spalling chimney.


Before any repairs can begin, the chimney sweeps will conduct an exhaustive inspection, allowing them to gauge the extent of the spalling and identify the underlying causes. Advanced inspections may use video scanning technology to get an in-depth look inside the chimney.


The chimney sweep will determine whether the spalling or crumbling bricks are superficial or if there’s more profound structural damage. The diagnosis will inform the course of action.

Estimate of Repair Costs

After inspection and diagnosis, a reputable chimney sweep service will give you an estimate and scope of the needed chimney repairs in writing. Beware the chimney sweep service that won’t give you an estimate in writing; it will allow them to increase the costs in the hope of defrauding you. Always insist you receive an estimate in writing before any repairs are performed.

Repairing the Damage

Brick Replacement

Severely spalled or broken bricks will need to be removed and replaced. A qualified chimney sweep service will carefully remove the damaged bricks without causing additional harm to the surrounding bricks. They will ensure the new bricks match the size, color, and material.


This method involves removing deteriorating mortar from the joints and refilling it with new mortar. Correctly done tuckpointing ensures that the chimney’s structural integrity will hold and prevent moisture from penetrating the brickwork.

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Crown Repair

The chimney crown, made of concrete or metal, is at the top and seals the chimney’s top edge. If the crown is damaged, it can be a significant cause of water entry, leading to crumbling brick and spalling. If the crown is indeed damaged, a chimney sweep service will repair or replace it as needed.

An Ounce of Prevention

After repairs on your crumbling chimney have been completed, it’s wise to waterproof it. This process involves applying a breathable sealant that prevents water from entering the brick while allowing moisture to escape. The sealant must be breathable; otherwise, trapped moisture can worsen the crumbling and spalling.

Chimney Specialist, Inc Can Repair Your Crumbling Chimney

If you live in Southwest Wisconsin, Northwest Illinois, or Northeast Iowa and have a crumbling chimney, call us at 608-929-4887 or complete our easy contact form. One of our chimney experts will gladly discuss repairing your crumbling chimney with you. Don’t wait until your chimney collapses; call us right away.

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