Four Reasons Why Concrete Cracks
Conditions that Lead to Concrete Repairs in Toronto
Concrete is used all over our cities and towns for its durability and versatility. Unfortunately, it is not permanent, and even the best-laid concrete can be susceptible to cracks. If you have recently noticed a shift or crack in the concrete structure of your building or surrounding area, it is wise to seek advice from concrete repair professionals. Small cracks can quickly lead to bigger structural damage, especially with Toronto’s unpredictable weather patterns. Prompt attention is important.
4 Causes of Cracked Concrete
Here are four common causes that lead to building owners across the GTA calling concrete repair contractors:
- Shrinkage – When concrete dries, it can shrink in size and leave gaps. The material is made from aggregate and cement paste, and that cement paste can shrink up to 30cm once it has completely dried. For this reason, cracks are inevitable. Their frequency and size is determined and offset by the amount of steel reinforcements, joints, and control joints that are embedded in the structure.
- Deformations – Over time, even after it has completely dried, concrete is prone to change. Typically during 5 to 10 years after completion, concrete structures face elastic creep deformations. These changes can reduce a 20-storey building’s overall height up to 30mm and lead to significant changes on successive floors. The changes are irreversible and should be accounted for in the initial build with horizontal control joints. If severe, the deflection of floors can lead to cracks that can extend to external brick work.
- Temperature and Moisture – Concrete will expand and contract when temperatures change. Expansion joints are used to minimize the risk of damage, but seasonal changes can swing so rapidly that these precautions are not always enough to avoid cracks. The material will also change with exposure to moisture. High humidity levels and dry conditions can lead to big variables in expansion and contraction. Toronto’s extreme seasons can easily cause cracks.
- Salt – Cement paste has a high pH level, so salt that gets embedded will not rust. The surface is not impermeable, though, and over time salt mixed with water can lead to rust and other damage to the structural bars underlying the concrete. Shifts in these foundational bars can lead to cracks in the concrete above. Roads and sidewalks that are covered in salt all winter long are particularly vulnerable to this kind of damage.
If you have cracked surfaces around your property, contact Zero Defects for Concrete Repairs in Toronto. We have experience with restoring small shifts and major damages, so your property remains safe and is restored to its former beauty. Contact us for an assessment to determine the right repairs for your needs before the harsh winter season.