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What Causes Cracks in a Chimney?

Many people usually contemplate and wonder what causes cracks in a chimney. This is after some actual realization that their chimney is gradually being damaged. Many homeowners have many assumptions about chimneys. They believe that a chimney is not a priority hence it is very poorly maintained because of the misconception that chimneys can indeed last for multiple years.

They usually forget that they are very prone and susceptible to cracks and splits due to multiple reasons. This issue, therefore, needs to be looked at deeply to decipher and elucidate the main causes of these cracks on a chimney. This article looks at exactly that.

  • Water and Moisture Leaks
Old cracked chimney on an old roof
Moisture is very lethal as it is responsible for most of the well-known chimney issues. A chimney crown and a mortar are purposefully meant to curb moisture from penetrating the masonry. Whenever the roof is constructed carelessly and without proper adherence to guidelines, water might start entering into the chimney. This makes it prudent to have a roof cricket installed, as it is very effective in guiding the water away from the chimney. To make it more comprehensible, when water and the subsequent moisture enter into the chimney, then there is some unexpected motion that ultimately results in these cracks however minor. More so, there might be some visible debris and this implies that there is moisture, which might be causing a lot of damage to the masonry. Sometimes the chimney cap might be missing or it might be faulty. This is at the top of the chimney. The chimney sides might also be experiencing some major issues where water might penetrate the chimney structure due to faulty flashing or the wind-blown rain. Freezing and thawing can also cause cracks on the flue liner or the chimney structure sometimes.

  • Winds

This is a major cause of these cracks hence they can easily ruin a chimney. Strong winds can therefore destroy the chimney due to the extreme tension exerted on the chimney. This niggling problem amongst many homeowners can only be remedied using steel rods during the construction of the chimney from the outset or way later when the situation spirals out of control.

  • Poor Construction

Even the slightest movement can cause cracks and splits in the masonry. Contractors might be very inexperienced, leading to some pathetic and sub-standard construction. This often leads to damage which many homeowners had not anticipated. It is common knowledge amongst professional contractors that it is vital to ensure there is a gap between the chimney and the flue lining. Therefore, there might be some expansion of the flue, which could result in the breakage of the brick. The chimney has to be properly anchored and reinforced by ample support and if this does not happen, then damage and cracks are inevitable.

  • Deplorable Drainage System

This is another cause of cracks in chimneys. When this happens, the water is not diverted away accordingly hence it accumulates and forms a puddle at the base. This leads to expansion and the shifting of the foundation. Eventually, cracks start to appear.

  • Mechanical Damage

This simply refers to the cracking of the chimney, which is often attributed to stress emanating from varying sources. This could be an antenna, which has been installed on top of the chimney. Some people also live in areas that usually experience many earthquakes of a very high magnitude. Others also live in areas close or proximate to a site with frequent or occasional blasts.

  • Settlement

It is quite crucial to ensure that you have a very good, strong, and sturdy foundation as you endeavor to undertake your project. The same applies to any kind of construction project such as a chimney system. If there is no proper foundation or settlement, then it is quite normal for the chimney to become frail and it immediately commences to lean. Ultimately, this only results in the most dreaded cracking. A found and fitting footing is therefore very essential to avoid some of these avoidable issues.

  • Poor Maintenance

The grout joints require a lot of regular and scheduled maintenance to curtail any instances of possible cracks. Bricks also require frequent maintenance. If you do not do the perfect sealing, cracking becomes inevitable and it can become major predicated on the scale of the negligence and failure to conduct the necessary maintenance.

This article has clearly illustrated and discussed the several causes of cracks in chimneys. You, therefore, stand to be properly guided. However, you should also liaise with experts in this area for further clarification in any area that might appear or tend to be blurry.