Above-ground pools are an excellent alternative to having an in-ground pool because they are cheaper and do not require weeks of construction work.
However, perhaps you’ve heard of some horror stories where people set up their above-ground pool on dirt only for it to slowly sink into the ground and tilt heavily to one side, eventually causing the pool walls to collapse.
Perhaps you already have a large concrete patio or concrete slab in your yard, or maybe you plan on pouring a concrete pad specifically for an above-ground pool to be installed on. Some questions you likely have are: is it a good idea to put an above-ground pool on concrete? What are the pros and cons?
Installing an above-ground pool on concrete is a great idea, but remember to place a pad underneath to protect the liner. Typically concrete slabs are level since they are initially liquid and gravity will cause it to level itself out. Furthermore, once cured, concrete provides much more support than dirt and you are less likely to encounter any issues with your pool slanting to one side.
Keep reading on to learn more about why you should install your above-ground pool on concrete.
Benefits of installing an above-ground pool on concrete
Flat and level
It is crucial that your above-ground pool is installed on a flat and level surface or it risks collapsing at some point in the future.. If your pool has a slant of even one inch, it becomes noticeable to the human eye. Technically the pool is still functional but you don’t want it to slant even more.
Even a two inch slant might start to cause issues. Depending on your standards, you might even consider disassembling the pool and re-leveling the ground beneath.
A three inch slant is definitely not okay. This is when the pool walls and frame can start to weaken over time as the extra pressure caused by the water shifting to one side starts to compromise the integrity of the materials.
Concrete pads can potentially solve this problem since concrete largely levels itself out when you pour it in liquid form. Yes, you still need to use a trowel to get it perfectly smooth and flat, but I think you get my point. Installing an above-ground pool on a perfectly flat and level surface is ideal.
One concern is if you already have an existing concrete slab in your yard. Most slabs or patios are intentionally off-level so that rainwater will naturally drain off of it. If your concrete patio is slightly uneven, make sure it does not cause more than a one inch slant, otherwise you may have some issues.
An above-ground pool frame is not that heavy. What’s really heavy is when the pool is filled with water. For example, 10,000 gallons of water weighs around 42 tons. That amount of weight will affect any grass, gravel, or dirt underneath.
Even concrete cannot hold up that much weight unless it is sufficiently thick enough. It is recommended that the concrete slab is at least 4 inches thick to be able to support an above-ground pool.
It seems odd to say this, but a concrete slab will protect your above-ground pool from the rain.
Many first time pool owners install their above-ground pool on dirt when it is nice and dry. Everything seems to go well at first, and perhaps they have many days in a row where it doesn’t rain. Suddenly the rain comes and down goes their pool. What happened?
When dirt gets wet, it just becomes mud and cannot hold up the gargantuan amount of pressure that a filled pool exerts on the ground. The pool legs will start to sink into the ground, and that’s when the unevenness starts.
There are also the issues of water seeping below the pool and fostering an environment for mold to grow, as well as animals and bugs digging through the dirt and damaging the pool liner.
Concrete, once cured, will continue to be stable even if it is raining. Grass will not grow through it, and animals and insects cannot burrow through concrete.
Use a pool pad to protect the liner underneath
While concrete is the best base for your above-ground pool to be resting on, it is not without its flaws. One such flaw is that concrete surfaces are stiff and abrasive.
This makes it uncomfortable for you to stand on for long periods of time, but can also result in the concrete surface tearing your pool liner.
To address these issues, you need to place a pool pad underneath your pool. Pool pads add a layer of protection between your pool and the concrete to prevent the liner from tearing. It is also soft and comfortable to stand on which makes the experience much more pleasant.
Can you use sand as a pool base?
No, for similar reasons why soil is not as good of an option as concrete is. Sand is also notoriously unreliable. When wet, it will simply wash away. In fact, it will naturally shift under the weight of the pool anyways. An unreliable base is about as effective as no base.
Why round above-ground pools are best for concrete
If you are thinking about installing any other shape other than a round one on concrete, then forget it.
Not even an oval pool will cut it. The reason is that the installation for an oval pool requires some parts to be on different levels. If you have a concrete slab already in place, that would mean either cutting some sections out of the concrete to make space, or building another layer above the concrete (which defeats the purpose of pouring a concrete base to begin with).
Rectangular pools are also not ideal. Their shape requires that additional cushioning and softness be present around the edges of the liner. Concrete is very hard and can result in high levels of tension in parts of the pool that are already prone to leakage. Basically, any pools with uneven sides or corners will not last as long on concrete.
For these reasons, a perfectly round pool is the optimal shape for an above-ground pool that is to be installed on concrete.
Photo Credit: Decorative Concrete Kingdom CC BY 2.0