There are two types of cracks in a concrete pool

A concrete pool is a pool that is built using concrete. Cracks will occur in a concrete pool. There are a number of reasons for concrete pool cracks.

Reasons for cracks in a concrete pool

Concrete does shrink, which can cause shrinkage cracks over time.

Perhaps there was an improper mix of water and concrete when the pool was built. If too much water was added to the concrete when the pool was built, the concrete will be weakened. This weakened concrete will crack over time.

Even with a shallow non-diving concrete pool, there is a lot of water weight and pressure on the shell. This pressure can cause cracks over time.

Perhaps the movement of the freeze/thaw cycle can cause cracks over time.

If a pool has leaked – and certainly still leaks – underground, that water will saturate, erode, and undermine the soil under and around the pool. The heavy concrete pool shell will not be resting on compacted earth. This will compromise the concrete shell, resulting in cracks. Never let a pool leak.

Types of cracks in a concrete pool

Some cracks are surface cracks, meaning they are barely embedded within the thickness of the concrete shell. A surface crack can be repaired by routing the crack, prepping and cleaning the crack, and then sealing the crack. A surface crack must be repaired before it becomes a structural crack.

Some cracks are structural cracks, meaning the depth of the crack penetrates through the entire thickness of the concrete shell. A structural crack will cause a pool to leak. This is known as a static leak source. A structural crack can be repaired by routing the crack, drilling-in injection ports along the path of the crack, injecting the crack, prepping and cleaning the crack, and then sealing the crack. The chemical to be injected will depend on the severity of the structural crack. It will also depend if ground water is seeping upward through the crack and into the pool. Regardless of the chemical being injected, any type of injection for structural crack repairs is expensive

Please be advised that a surface crack can – and likely will – continue to penetrate the thickness of the concrete shell. Over time, if left untreated, a surface crack will become a structural crack (and therefore a leak source).

Notes about cracks in a concrete pool

When the pool is empty, the crack may not look significant. But when the pool is filled, the extreme pressure of the water weight on top of that crack will cause it to widen. This makes crack repairs very hard to inspect and diagnose.

Any crack will compromise the strength, structure and integrity of the overall concrete shell.

Some cracks start as surface cracks and become structural cracks. Other cracks are structural cracks immediately. Surface cracks are a minor problem. Surface cracks that are neglected, though, will soon become a real problem. Structural cracks are a big problem that will be significantly more expensive to repair.

It is essential to repair and eliminate cracks in the concrete shell once the crack is recognized.


We hope this help.

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We repair all cracks in concrete pools.

Whether your concrete pool has surface cracks, structural cracks, or both types of cracks simultaneously, we can repair and eliminate the cracks.

If you suspect a crack in your concrete pool is structural crack – and therefore a leak source – we do have leak detection equipment that will confirm this suspicion.

We can handle any interior repair for your concrete pool, to include all crack repairs.

Call us at 402-341-8132 or send us an email to info@expertpoolwork.com or submit a short form to discuss your pool and schedule free onsite consultation.