Ask an experienced pond keeper, "What's the best pond liner material available?", and they'll almost certainly say rubber. For years, rubber pond liners have been considered the best type of pond liner available for garden ponds and other outdoor projects. But what makes rubber pond liners great, how do they differ from other pond liners, and how long do they last? Let's answer some of those questions...

What are rubber pond liners made of?

Most rubber pond liners are made from a synthetic rubber material known as EPDM (ethylene propylene diene monomer). These pond liners are made using a high-pressure, high-heat process that mixes rubber polymers - in this case EPDM - with oils, carbon, and other substances to give the material its characteristic strength and flexibility. Thanks to its unique chemical structure, EPDM also has fantastic resistance to high/low temperatures and UV radiation.

Traditionally, rubber pond liners were made from another type of synthetic rubber material known as butyl. Like EPDM pond liners, butyl rubber pond liners are highly flexible and easy to install, particularly in a custom-built garden pond. That said, they're not quite as durable as EPDM rubber pond liners and tend to be more susceptible to rips and punctures. This is largely the reason that, nowadays, EPDM rubber pond liners are the most popular type of rubber pond liner available.

EPDM rubber pond liner lining a nature pond full of aquatic plants
EPDM rubber pond liners are renowned for their durability and flexibility

What are the differences between rubber pond liners and other pond liners?

Just like other types of pond liners, rubber pond liners form an impenetrable layer between the water in your pond and the ground underneath - in short, they support your garden pond and all of the aquatic life inside it. There are several things unique to rubber pond liners, however, that make them a better choice than, say, HDPE pond liners or PVC pond liners.

Unlike these other two popular types of pond liner, rubber pond liners don't expand or contract at high/low temperatures. This means that large temperature swings won't cause your rubber pond liner to lose its grip on your ground's surface and, as a result, fail. They're also resistant to UV damage and general wear and tear, which helps them last a lot, lot longer than alternative options.

While PVC pond liners are quite soft, rubber pond liners are widely considered the most flexible and easiest type of pond liner to install. Thanks to their construction, they can stretch without losing strength, mould tightly around nooks and crannies, and lay flat against your garden pond's bottom and sides. This makes them the number one choice for pond keepers looking to line large, intricately dug garden ponds.

Large, outdoor pond surrounded by marginal bog plants
Rubber pond liners are a great choice of pond liner for large outdoor ponds

The only downside of rubber pond liners is the fact that they can be quite expensive, their price tags significant larger than those of HDPE pond liners and PVC pond liners. That said, you get what you pay for with rubber pond liners: durability, flexibility, atmospheric resistance, and long-life. We have several EPDM rubber pond liners for sale on our website, our Swell UK branded EPDM rubber pond liner and two from industry experts Gordon Low.

How long do rubber pond liners last?

If properly installed on top of a layer of quality protective underlay, rubber ponds liners can last for decades (upwards of 30 years), supporting a thriving community of fish for generations. At Swell UK, we're so confident in the durability of our rubber pond liners that we sell them with a lifetime guarantee included.

This guarantee covers your rubber pond liner against UV damage - the main cause of pond liner degradation. It doesn't, however, cover it against rips and punctures; though given the construction and composition of rubber pond liners it's unlikely that yours will ever experience this kind of irreparable damage.

Do rubber pond liners need underlay?

While they may be the most durable type of pond liner available, rubber pond liners still need to be partnered with some proper protective underlay. A layer of protective underlay will not only protect your rubber pond liner from any underlying twigs and stones that may puncture it, but also stop it from shifting due to any surrounding ground movement. It will also serve as a layer of insulation, retaining some much-needed heat during those cold winter months.

Rubber pond liners can be easily cut to size using a pair of sharp scissors
All pond liners should be supported by a layer of protective underlay

How do you repair a rubber pond liner?

When fitting a pond liner, accidents can happen and you may damage your rubber pond liner. Thankfully, rubber pond liners - including EPDM rubber pond liners and butyl rubber pond liners - can be repaired relatively easily using a dedicated pond liner repair kit or a leftover piece of rubber pond liner cut to size.

Start by cleaning the damaged area and making sure it's free of any algae and/or debris. Then, cut your patch into an appropriately sized circle - circles are better than squares/rectangles as they don't have corners that may potentially curl up and fray.

Once you have your patch prepared, run a continuous bead of sealant around the patch and press it firmly onto your rubber pond liner. For best results, leave it to dry for at least 24 hours before you re-fill your garden pond.

For a closer look at the pros and cons of other pond liner materials, check out 'Everything You Need To Know About Swell UK Pond Liners'. And for advice on how to install your new pond liner, check out 'How To Install Your New Pond Liner: A Step-By-Step Guide'.