Why does a Swimming Pool Crack?

What causes cracks in swimming pools? Cracks can be caused by a number of issues, we’ll take a look at a few in this blog. Once a swimming pool is cracked, seek advice and remedial services from a reputable swimming pool builder that belongs to the professional association in South Africa, namely, the National Spa and Pool Institute (NSPI).

One of the fundamentals when building a swimming pool is to make sure the ground you’re building the pool into is suitable. Very often, pool builders who belong to the NSPI in South Africa have had enough experience to [read more] know whether the soil is going to cause a problem down the line or not. The second part to building a good, solid swimming pool is to make sure the specifications (or minimum specifications) are adhered to. For example, the NSPI in South Africa insist on a certain size and type of reinforcing steel depending on the size of the pool and the soil conditions. Sometimes the appointed engineer may request the builder to underpin the pool with piles to prevent the shell from settling or moving and cracking.

BLUPOOL, a reputable swimming pool construction company in Durban North, recently had the task of rehabilitating an 8m x 4m swimming pool which had cracked in several places. On closer inspection of the pool, we discovered that the pool did not have a ring beam around the top of the shell, and the shell had also settled. The movement caused long downward cracks in the swimming pool, and the pool ‘leaked like a sieve’. There were also places in the surrounding paving that the bricks had sunk into hollows in the soil.

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Our first activity was to drain the pool and uplift the paving around the swimming pool. We then opened up spaces next to the shell which would enable us to build reinforced concrete ‘pillars’ to which we could strap the shell. We then stitched the cracks in the pool with steel ‘staples’ and strong epoxy. Finally we cast a steel reinforced ring beam around the pool which would hold the pool shell in place. 

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Once we were happy that the pool was stable and strong enough to hold water, we re-tiled the scum line and plastered the pool with a good quality Marbelite (marble plaster mix). The preparation of the the pool surface before plastering is essential for longevity of the marble plaster. If done correctly, and with properly balanced water after the pool is filled, black algae, rough patches and pitting will not be in issue for many years to come. A good, well rounded pool company that is proficient in all areas of swimming pools (building new swimming pools, renovating swimming pools, maintaining water balance in swimming pools) will always balance the pool water after re-filling the pool and before handing it back over to the pool owner.

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Avoid the temptation of getting as many quotes as possible and going for the cheapest pool contractor. Nine times out of 10 this will backfire and end up costing more money a few years down the line. Unscrupulous pool contractors that undercut reputable companies will take short cuts without the pool owner even knowing. These short cuts will manifest into problems down the line, and the pool contractor can often not be found.

Do your homework, get a good pool contractor not a cheap one, and finally, happy swimming!