Concrete slabs are essential for a home’s foundation. They provide a flat, even and supportive surface for the home to be built on. There are many types of slabs now including waffle, raft slabs, flat slabs, plate slabs and more.
If cracking occurs in your concrete slab during the construction process, our experienced team can carry out an inspection and provide you with a detailed report outlining the structural integrity of your slab, offering advice on remedial solutions where required.
Causes of slab cracks:
- Too much water in the concrete mix
- Too hot of weather while the concrete is drying
- Too much weight placed on the slab
- Roots of a large nearby tree can spread underneath the slab and cause it to crack from the pressure
- Cracks can occur if a tree dies or is removed near the home if the roots were under the slab as it causes movement and a change in moisture.
- Flooding can cause the soil to rapidly expand which places pressure on the slab
- Drought can cause the soil to shrink which affects the support for the slab
- The ground underneath the slab settling can also cause cracks, slabs built on top of dirt with high reactive clay levels are more likely to experience movement
Some warning signs of a foundation problem include:
- Visible cracks in the concrete slab
- Cracked/loose tiles
- Cracks in walls
- Doors/windows jamming
- A sagging ceiling
- Uneven or creaking floors
Small cracks and shrinkage in the slab are common while the ground settles and may not compromise the structural integrity of the home, however, it is often very difficult to determine how deep the cracks run without a proper inspection.
Repair solutions must be long-term and address the causes of the cracks as well as repairing the actual crack. Repairs should only be undertaken with the advice of a qualified and licenced professional. Using the wrong repair techniques can result in more damage to the slab. Cracks that are identified as small and fine (less than 0.3 mm in width), are typically accepted as part of settlement. However, a crack should be inspected and diagnosed to classify the severity of the crack, the cause of the crack, and determine the most effective repair method. If the slab has multiple small cracks or cracks wider than a few millimetres, it’s best to request an inspection from a structural engineer. For extreme cases, it may be necessary to seek the advice of a geotechnical engineer, in order to determine the root cause.
If cracking occurs in your concrete slab, our experienced team can carry out an inspection and provide you with a report outlining the structural integrity of your slab, offering advice on remedial solutions where required.