What Do You Put Under an Above Ground Pool?

Above ground pools are becoming more and more popular. They are much more affordable than your traditional in-ground pool, but can offer the same benefits.  The most important one being fun!  But before you build your pool, or have it delivered and installed, let’s chat about what options you can use to put underneath your new pool.  After all, water is heavy!  I learned that a 24’ long pool with a depth of 54” can weigh upwards of 112,000 pounds? Wowza! So don’t start adding the water just yet.

Why Do I Need a Base for My Above Ground Pool?

We already chatted about the weight.  Pool Bases provide extra strength for the pool.  They also help prevent erosion and can help prevent the liner from tearing.  They help keep the swimming pool level.  Keeping the pool level is important to keep that heaviness balanced.  They also help keep the shape of the pool.  A misshapen pool will give you an uneven water line.  They also help prevent your biggest problem: the pool wall collapsing!  Placing your pool helps reduce the risk of wearing and tearing of your pool liner.

The ground underneath can erode or shift.  Especially after rain.  This is all bad dot com.  A firm foundation helps keep your pool strong and stable.  It also helps the bottom of your pool from getting lumpy.  Who the heck wants lumps?  Here are some of the options for underneath your above ground pool along with some pros and cons.


Also known as dirt.  This method is great for DIYers and is very inexpensive.  You will need to tamp and level the ground first.  The downside is that you are more prone to erosion, which can cause your pool to collapse if for some reason the ground becomes unlevel.

Pool Pads & Protective Layers

These are pretty affordable and work well with a concrete or gravel base.  These pads help make the bottom of the swimming pool smoother.  The downside is it is an additional cost and may not even be necessary if you go with another pool base.

Stone Dust

This was a new one to me as I had never heard of it.  It can be a great cushion for your swimming pool.  It also offers protection for underneath your pool liner.  The downside is that stone dust has poor drainage and isn’t as easily compacted like concrete, even though it hardens like concrete.  This is the reason it is cheaper.

Mason Sand

This brings us to the most popular option.  This material provides a cushion which can be softer on the pool floor.  It can make walking around your above ground pool more comfortable.  It is one of the softer materials.  I learned that the downsides are that it is also prone to erosion.  It can also be annoying to have sand in your backyard. Footprints can also develop on the pool’s floor.  The most horrifying downside to me is that animals may burrow underneath and weaken the foundation!  Ewwwww.


Another method I had to learn about, having never heard of it.  This method offers a secure foundation that is also flexible.  What I mean by flexible is that it allows for water drainage.  You also are in luck because it will not crack if the ground were to shift.  The downside is it can breed algae.  Great.  Now we have to worry about algae in the pool and underneath.  I may want to rethink this one.


Now we have come to a heavy-duty favorable option.  This material offers wonderful drainage.  Gravel is also quite sturdy.  It can be a great option if your pool foundation is on a slope, because it can be leveled to the deck height.  The downsides are it can get expensive and isn’t quite as comfy on your bare feet.


This is considered the “best” method.  While pricey, many consumers find the cost validated due to its durability.  Especially since you are already investing in a pool that will last you for years!  Concrete helps prevent nut grass as well.  You don’t have to worry about weeds puncturing the pool liner.  Concrete is also clean, both in looks and the smoothness it offers.  Unfortunately, this is the most expensive method and doesn’t offer the best drainage.  Don’t forget the pad that is needed between the concrete and the pool!

As you can see, there are many options when choosing the above ground pool base you want to go with.  I would go as far as to ask, how expensive was the pool?  Will I use it year after year?  WIll I leave it up in the off season?  Things like that.  I would like to give a shout out to my friends at siteprep.com for helping me understand a little more about what an above ground pool base entails.  See you poolside!