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- Thick 0.35mm HDPE pond liner
- Supple, UV resistant and 40-year guarantee
- Available in a wide variety of sizes

Palletised delivery
Large sizes may be delivered on a pallet for protection in transit.
"Brilliant, prompt service. Clear instructions."
What is the Swell HDPE Pond Liner 40-Year Guarantee With Free Underlay?
The most popular Swell UK pond liner, the Swell HDPE Pond Liner 40-Year Guarantee is designed to be laid over the included underlay and stop your water garden from draining into the earth beneath it. This liner is made from 0.35mm-thick HDPE which is UV-resistant and supple, for an easy setup and long-lasting durability. We sell this liner with a 40-year guarantee against UV damage for added peace of mind.
Is this pond liner easy to lay?
Yes, high-density polythene (HDPE) pond liners are very supple, making installation a breeze and creating a good seal around your pond.
What size pond liner do I need?
To find the correct size of pond liner you'll need, you can use our Pond Liner Calculator. Our calculator will give you the minimum length and width of pond liner you'll need to completely line your pond based on its length, width and depth. There's no need to worry about the size of your pond liner underlay as we'll match the size of your liner with an appropriate underlay.
What does the guarantee cover?
This Swell Pond Liner carries a 40-year guarantee, but we also have other variations with lifetime guarantees. As with every pond liner sold in the UK, the guarantee covers UV damage only, not punctures.
Do I need to buy anything else with this liner?
We recommend always investing in a pond liner repair kit to ensure quick repairs and avoid draining.Â
Features
Material | HDPE |
Thickness | 0.35mm |
Colour | Black |
Liner suppleness | Very |
Liner stretchiness | No stretch |
UV resistant | Yes |
Guarantee | 40 years |
Underlay included | Yes |
Underlay type | Standard |
Underlay colour | Black |
Pond sizes | Small-large |
Koi window compatibility | Not suitable |
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