Soil Settlement Beneath A Concrete Pool Deck

Posted on: 4 May 2021

Anyone who installs a backyard swimming pool needs to be prepared for the upkeep. It's a lot of work, but the payoff is worth it. It can be disconcerting when your concrete pool decking mysteriously begins to shift and tilt, especially when you've put in so much effort to maintain your pool. What could be causing this displacement, and is it anything to do with your pool?

Concrete Slabs

The displacement of your pool deck's concrete slabs is not only an aesthetic concern. It can also create a tripping hazard, which can be dangerous next to the water's edge. Additionally, it's annoyingly easy to snag your bare feet on these newly exposed sharp edges. What can be causing this displacement?

Sinking Action

Some (or possibly, all) of your pool slabs may have become sunken. This sinking action is not evenly distributed across the slabs, and individual slabs are likely to sink at a slight angle, which creates those sharp edges and tripping hazards. The issue is typically due to a change to the soil beneath the slabs.

Checking for Leakage

It must be ascertained that the pool is not leaking, although this is straightforward to diagnose. The water level of the pool will be reducing at an accelerated rate — more so than will have been caused by evaporation. A crack will often be visible in the wall of the pool, and it's likely that there will be sodden patches on your lawn. When these indicators are not present (meaning that leakage is not affecting your concrete pool deck), the likely culprit is simple soil settlement.

Compression of Soil

This soil settlement beneath concrete pool slabs is a common occurrence. It's essentially the compression of the soil beneath the weight of the concrete. This is a gradual process, which is why the displacement has been slow and steady. The issue can be aggravated by weathering, wherein the concrete slabs have expanded and contracted in response to heat and moisture. Does this mean that the slabs will need to be replaced?

Stabilizing the Slabs

Pool deck repair should not be delayed, otherwise, the displacement of the slabs can lead to irreparable warping or cracking (in which case replacement is unavoidable). However, it's generally just a case of stabilizing the slabs. The void created by the soil settlement will be filled, and this can be achieved with a grout composed of sand and cement. You will be advised not to use the pool deck while the filling agent cures beneath the concrete decking. 

Displaced concrete decking can hamper your enjoyment of your swimming pool, and the issue is likely to worsen without repair.

For more information, contact a local pool deck repair service.