What material should be used for a hydrotherapy pool? Concrete, GRP, or stainless steel?

Hydrotherapy pools are specialist pieces of equipment and may need to be constructed from different materials to perform at the best level. The three most common materials used for constructing a hydrotherapy pool are concrete, glass reinforced plastic/fibreglass (GRP), and stainless steel. But which is the best one for you?

Concrete & Tiled

Concrete is probably the most popular material used to build all kinds of pools. Concrete pools are then tiled over to look like a traditional swimming pool. However, this isn’t necessarily the most effective way or long-lasting hydrotherapy pool material. Because of the higher temperature in hydrotherapy pools, it’s not uncommon for a tile to crack or pop out of place which is particularly troublesome and time-consuming to fix.

Concrete and tiled pools also take longer to install in the first place and have higher ongoing maintenance costs because of cleaning and re-grouting.

Additionally, concrete pools also provide a surface for bacteria to harbour. Cracked tiles and grout all provide a comfortable, warm, moist surface where mould and bacteria can grow. This is particularly detrimental in environments where infection control is a main concern (e.g.- SEN schools, rehabilitation centres, hospitals).

Underwater in a tiled hydrotherapy pool.
Concrete and tiled pools have been the only choice in the past, but they’re not necessarily well-suited to hydrotherapy and be more expensive.

Glass Reinforced Plastic (GRP)

GRP hydrotherapy pools are made and installed a little differently. Because they’re made from fibreglass, GRP pools are fairly strong and resist erosion – which is ideal for hydrotherapy pools. The structure is a single piece that has been moulded specifically to the client’s needs and specifications. It looks smart and can be supplied in different colours.

Although GRP pools are good, they do have their downfalls – particularly in areas of hydrotherapy and physiotherapy. Many GRP pools are built to withstand higher temperatures, but that does not necessarily include the standard hydrotherapy pool heat. Hydrotherapy pools need to be heated anywhere between 32°C and 36°C. Lots of GRP pools can’t withstand this heat, which is of course a significant issue.

Another thing to consider with GRP pools is the actual shape of the mould itself. It isn’t possible to get a 3-corner bottom on a GRP pool, so the edge of the pool can often have a significant curve. This makes it very difficult to stand comfortably at the edge of the pool, which is usually where a portion of physiotherapy will take place. It also makes it difficult if your pool has a rail mounted to the side to hold on to. If the carer/physiotherapist can’t find good footing, then how will the client?

Stainless Steel

Stainless steel is a particularly robust material, and it can be used to make hydrotherapy pools. Like GRP, it is made in one singular mould and then craned into position. Stainless steel is strong, corrosion-resistant, and particularly long-lasting. Furthermore, it can be crafted to the absolute perfect size and shape for the client’s needs.

One area where stainless steel really excels is in infection control. There are literally no parts of the pool where bacteria can latch on and grow, which is great for multi-user environments where infection control is key. Stainless steel is also cheaper in the long-run. Because they require less maintenance, stainless steel pools end up being more cost-effective over time, which is a huge advantage.

Another benefit of stainless steel is that it can easily withstand the temperatures required for hydrotherapy. It’s also a particularly safe surface when wet; it’s practically impossible to slip on wet stainless steel! Even better, they’re very quick to install in comparison with concrete models, and some come with a 30-year guarantee.

A stainless steel hydrotherapy pool installed into the ground
Stainless steel hydrotherapy pools can be made in any shape or size to suit the user’s preference.

These three materials are the most popular when it comes to hydrotherapy pools, and they each have their advantages. Whilst tiled/concrete models look the most traditional, they’re not always to most cost-effective or easiest solution to go with. GRP and stainless steel are much more robust, but for us, stainless steel is probably the most reliable and long-lasting hydrotherapy pool material available. Find out more about stainless steel hydrotherapy pools here.