Steel Vs Polymer Pool Walls: Which One Should You Choose?



Installing a vinyl liner pool in your backyard is never a bad idea.

Not only will it give you your own tropical oasis, but they can last decades when well taken care of, and are more affordable than concrete or fiberglass pools.

Construction of vinyl liner pools is relatively straightforward, with the pool walls being made of either interlocking steel or polymer panels, before the vinyl liner and decking is added.

When deciding between steel or polymer pool walls, both provide an excellent structural shape for a vinyl liner pool, but there are pros and cons to each.

Steel Walls: Pros & Cons

Steel is one of the most widely used building materials available, and for good reason. However, there are times when you won’t want to use this material for your pool walls.


  • It’s strong. There’s a reason why so many skyscrapers use steel in their construction. It is strong! Vinyl liner pools need very strong walls to withstand the hydrostatic pressure the water exerts toward them. With steel, it won’t bend or warp, giving your pool excellent structural integrity.
  • Adjustable walls. With any pool, you need to make sure it’s levelled properly. Steel walls come with an adjustable turnbuckle brace that allows you more control over how the walls sit. This makes it easier to level and plumb, so your pool won’t be oddly titled or angled.
  • Can backfill after installing liner. The benefit of backfill after the pool has been filled with water is that you still have access to all the piping. This makes it beneficial as you can see if there are any issues with the pool from the get go. It’s like being able to run your car and look under the hood at the same time. 
  • Cheaper. This is a big one for many people. Steel wall panels are less expensive than polymer panels. At one point, the price difference was thousands of dollars worth of savings, but this has come down over time. Still, you’ll pay less for steel over polymer.


  • Will rust. Steel is prone to rust, and this is no different with steel panels. However, newer models include a rust proof galvanized coating on the panels. This will slow the process down, but not stop it entirely. Rusting can happen through tiny cracks in the pool’s construction, or from the outside of the pool if the soil is wet.
  • Laborious install. Due to the weight of steel, it’s not as easy to handle, maneuver, and set in place as polymer panels are. This will make the install take a little bit longer, and require more elbow grease from the installers.
  • Not for saltwater pools. If you’re going to be using a salt cell with your pool, you can’t use steel panels. Salt eats through steel. While the vinyl liner provides a barrier between the water and walls, there will still be leaks here and there which will ultimately destroy the walls and compromise the pool’s structural integrity.

Polymer Walls: Pros & Cons

Polymer has become the fastest growing construction material, as it can be used for many different types of applications. But, like steel, it does come with its upsides and downsides when used for swimming pools.


  • Less overdig. When excavating, enough room must be made not only for the walls, but for the plumbing that goes behind them. Due to the design of polymer panels, less overdig is required, making them ideal for small backyards where space is an issue.
  • Highly durable. Polymer panels are highly durable and can take a beating without getting damaged. Not that we’d expect you to be kicking in your pool walls with a steel-toed boot, but it’s nice to know that you could and still not make a dent.
  • Lightweight. Unlike steel, polymer panels are lightweight. This makes them easier to lift, handle and set in place when installing them (your installers will thank you).
  • Ideal for wet soils. Also unlike steel, polymer doesn’t rust or corrode. Not only does this make them perfect for saltwater pools, but they are also excellent walls for backyards with wet soil.


  • Less rugged. This isn’t to say they aren’t rugged, but rather they’re less rugged when compared to steel. But fear not, polymer panels can withstand hydrostatic pressure forces and will hold up over time – which is really all you need the walls to do.
  • More expensive. The price of polymer panels isn’t quite as high as they were when they originally came out, but compared to steel they’re still the more expensive option.
  • Bad for cold climates. If you live in a frigidly cold climate, you might not want to go with polymer. It has no expansion and contraction capability when there are extreme temperature fluctuations. This can lead to cracks appearing in the panels.
  • Backfill when filling the pool. Backfilling and filling up the pool with water need to be done at the same time. This is to ensure there is equal amounts of pressure on the inside and outside of the panels, keeping them from shifting.

Steel Vs Polymer Pool Walls: Verdict

Both steel and polymer pool walls provide excellent structure to a vinyl liner pool. 

So which one should you choose?

There is no “better” option, but for our money, we would choose polymer (even though it is a bit more expensive). 

While not at the same strength level as steel, polymer is still plenty strong, and their light weight will make for an easier installation. They also won’t ever rust, or corrode, and you can use them for both chlorine or saltwater swimming pools for years to come.

Categories: Pool Care, Pool Construction