If you look at your chimney and wonder, why is my chimney cracking? – you shouldn’t take this lightly. A crack in your chimney may be more than just a cosmetic flaw. Even a hairline fracture can compromise your chimney stack, putting it and your home at risk for expensive damage from moisture and even fires.
Consulting with a masonry contractor is always a wise choice if you’re unsure about the condition of your brick structure.
Cracks may even expose you and your family to carbon monoxide poisoning, which can be deadly. Keep reading to discover five common reasons for cracked chimney brick and what to do about it.
Five Reasons Chimneys Crack
Whether you see hairline cracks or large structural cracks in your chimney, it indicates that something is wrong. Here are five common reasons your chimney has cracks.
The Freeze-Thaw Cycle
Although bricks are hard to the touch, they are very porous. This means that they can absorb moisture throughout the year. Combine this with cold or humid air, and bricks are subject to contracting and expanding. The expansion and contraction of bricks through the freeze-and-thaw cycle throughout the year can cause them to crack, flake, or spall.
A Damaged Chimney Crown
Cracks in the bricks of your chimney aren’t the only cracks you should worry about. The crown of the chimney may be made of a concrete slab that tops the chimney. It helps keep water and small wildlife out of your fireplace. It may also help catch the sparks that shoot out as you burn fires in your fireplace.
Like brick, concrete is also porous. Throughout the year, as the crown is exposed to heat and cold externally and from within the fireplace, it can expand and contract, causing cracks. These cracks may allow water to flow into your fireplace instead of away from it, leading to damage within the chimney and the fireplace. It can also cause cracks within the brickwork.
Thermal Shock from Heat Expansion
Another reason your chimney may crack is from using it. During the extremely cold winter months in Michigan, you may want to warm up your space by lighting a fireplace. When you light the fire on a frigid winter night, your chimney could face extreme thermal shock. This happens when you use it on a very cold night after it hasn’t been used in a while. While thermal shock may not cause much damage the first time using it on a cold, wintry night, prolonged use may create stress fractures in the interior flue liner and brickwork. This may lead to cracks in the chimney.
Aging Mortar Joints
Bricks may last for up to 100 years. However, the mortar between them has a life expectancy of 20 to 25 years. As mortar ages, it may crack or be completely removed by heavy rains or high winds. As this occurs, your bricks may undergo cracking, or worse, they could completely collapse, causing severe structural damage to the chimney bricks.
Natural Foundation Settling
All homes settle over time due to shifts in the soil. However, some homes may experience more settling than others. As a result of this movement, your home could shift, causing cracks in your chimney bricks. While these cracks may be cosmetic, you should still get the help of a brick mason to resolve any issues you may have with cracks in your chimney. In some cases, due to settling and soil erosion, cracks in your chimney may be structural. Before a brick mason can fix these cracks, you may need to get the help of a foundation repair company.
Expert Masonry and Chimney Repair in Rochester Hills
Cracks in your chimney or any brick structure can lead to bigger problems if they’re ignored. Primo Contracting in Rochester Hills provides experienced chimney repair and masonry services for homeowners and businesses throughout the area. Our services include brick repair and replacement, tuckpointing and repointing, chimney masonry repair, retaining walls, and other custom brick and masonry construction projects.
If you’ve noticed cracked bricks, loose mortar, or other signs of chimney damage, contact Primo Contracting today and speak with a masonry expert.