Masonry structures, made of brick, stone, or concrete, are prized for their strength and durability. However, like any building material, masonry is not immune to wear and tear over time. One of the most common issues homeowners encounter is cracks in masonry. These cracks can vary in size and severity, but they often indicate underlying problems that need to be addressed to maintain the structural integrity and appearance of the building. Today we’ll be going over some of the common causes of cracks in masonry and provide guidance on how to address them effectively.
Common Causes of Cracks in Masonry
Settling of the Foundation: The natural settling of a building’s foundation is a frequent cause of masonry cracks. As the soil beneath the foundation shifts or compresses over time, it can cause uneven movement in the structure. This movement places stress on the masonry, leading to cracks. Small, hairline cracks are often a normal part of settling, but larger or widening cracks may indicate more significant foundation issues that need immediate attention.
Moisture and Freeze-Thaw Cycles: Masonry is a porous material, meaning it can absorb water. When temperatures drop, this trapped moisture can freeze and expand, causing stress on the bricks, stones, or mortar. As the ice thaws, it leaves behind cracks or worsens existing ones. Repeated freeze-thaw cycles exacerbate the problem, leading to spalling (flaking or peeling of the masonry surface) and deeper cracks.
Thermal Expansion and Contraction: Changes in temperature can cause masonry materials to expand and contract. Over time, this thermal movement can lead to cracks, especially in areas with significant temperature fluctuations. Without proper expansion joints or flexible materials to absorb this movement, the masonry becomes more susceptible to cracking.
Poor Construction Practices: Improper construction techniques, such as using the wrong type of mortar, insufficient curing time, or inadequate support, can weaken masonry structures and lead to cracks. For example, using a mortar that is too strong for the bricks can create stress points, as the mortar doesn’t flex or accommodate movement as intended.
Tree Roots and Vegetation: The roots of nearby trees and plants can exert pressure on masonry foundations and walls as they grow and spread. Over time, this pressure can cause cracks to form. Vegetation growing directly on masonry surfaces, such as ivy, can also exacerbate the problem by trapping moisture and promoting deterioration.
Structural Overloading: Masonry structures are designed to carry a specific load. If additional weight is added beyond what the structure was designed to handle—such as through renovations or poorly supported extensions—it can result in cracks as the masonry struggles to bear the excess stress.
Earthquakes and Vibrations: Seismic activity, even in areas not prone to major earthquakes, can cause cracks in masonry structures. Smaller vibrations, such as those caused by nearby construction or heavy machinery, can also contribute to cracks over time.
How to Address Masonry Cracks
The best approach to addressing masonry cracks depends on their size, cause, and severity.
Evaluate the Severity of the Cracks
Start by determining whether the cracks are superficial or structural. Superficial cracks are often small and limited to the mortar or surface of the masonry. These can typically be repaired easily. Structural cracks, on the other hand, may indicate significant issues with the foundation or load-bearing capacity of the structure and require professional evaluation.
Repair Minor Cracks
For minor cracks, clean the affected area thoroughly to remove dirt, debris, and loose material. Fill the cracks with a suitable masonry repair product, such as mortar mix, epoxy, or a masonry crack filler. Be sure to match the color and texture of the repair material to the existing masonry for a seamless finish.
Address Underlying Causes
Repairing the cracks without addressing the root cause will only lead to recurring issues. If settling or soil movement is the problem, consider stabilizing the foundation. For moisture-related cracks, improve drainage around the property, apply waterproofing treatments, and repair gutters and downspouts to direct water away from the masonry.
Reinforce the Structure
In cases where cracks are caused by structural overloading or poor construction, reinforcing the masonry may be necessary. This can involve adding support beams, installing ties or anchors, or replacing damaged sections of the structure. Consult a professional mason or structural engineer for the best approach.
Install Expansion Joints
To prevent future cracks caused by thermal expansion and contraction, install expansion joints in strategic locations. These flexible joints allow the masonry to move naturally with temperature changes without causing stress on the structure.
Remove Problematic Vegetation
If tree roots or climbing plants are contributing to the problem, take steps to remove or manage them. In some cases, relocating the tree or installing root barriers may be necessary to protect the masonry from further damage.
When to Call a Professional
While small cracks can often be repaired as a DIY project, larger or structural cracks should be evaluated and repaired by a professional mason. A trained expert can assess the extent of the damage, identify the root cause, and implement the most effective solution to restore the masonry’s integrity.
Protecting Your Masonry for the Long Term
Cracks in masonry may seem like a minor issue at first, but they can quickly escalate if left unaddressed. Understanding the common causes of cracks and taking proactive steps to repair and prevent them can save you from costly repairs and preserve the strength and beauty of your structure.
If you’re dealing with cracks in your masonry, don’t hesitate to contact Turnbull Masonry. Their experienced team can assess the damage, identify the cause, and provide expert solutions to restore and protect your brick, stone, or concrete structure for years to come.
