A pond liner appears significantly more natural and allows for more flexible design than a prefabricated or concrete pond. If you want to create a pond liner, you are faced with the question of which pond liner to buy. The liner is available in various thicknesses and materials, each with its own advantages and disadvantages. Liners are also suitable for larger and deeper garden ponds, as well as swimming ponds. The maintenance effort is manageable. This post provides information about the different types of pond liners.
Properties of Pond Liner
A pond liner is a special material that ensures the waterproofing of your garden pond from below. It must be flexible to adapt to the shape of your pond. The pond liner forms a protective layer between the pond’s base and the water. As there is water in your garden pond throughout the year, the liner must be completely waterproof and stable. It is also crucial to be resistant to scratches that may occur due to a moment of carelessness. Frost resistance is also essential because the pond liner is exposed to temperatures below minus 10 degrees Celsius in winter. In summer, the water level in your pond drops, exposing the liner to the sun. Heat and UV resistance are crucial properties of a pond liner. The liner must be absolutely compatible with plants and animals. These are numerous requirements that a pond liner must meet, and the various materials from which pond liners are made more or less fulfill these requirements.
The Main Materials of Pond Liner Overview
Pond liner is generally available in three different materials:
- PVC (Polyvinyl chloride) as the most commonly used material
- PE (Polyethylene) as a relatively environmentally friendly material
- EPDM as a material from the Ethylene-Propylene-Diene-M group, based on rubber
Liners made from all these materials are available in different thicknesses. Usually, the pond liner is black, although green liners are occasionally offered. There are also liners made from special geotextiles, but these are rarely relevant for your garden or swimming pond; they are seldom used.
PVC Pond Liner: The Standard Liner for Small and Medium Ponds
PVC pond liner is the standard liner and has been offered for garden ponds for the longest time. This liner has some good properties. It is flexible and can be laid easily. Gluing the liner is also straightforward. Other positive properties include durability and robustness. The liner is suitable for small and medium-sized ponds, and it adapts well to the base, making it suitable for ponds with complicated shapes. However, folds can form during the installation. PVC liner is mostly available in black, but it is also offered in green, blue, or brown. It is available in thicknesses from 0.5 to 2.0 millimeters. If the PVC liner ever develops a hole or tear, you can repair it with pond liner adhesive or liquid PVC. PVC liner can be laid at temperatures above 15 degrees Celsius. The material becomes stiff when it gets too cold, so it is advisable to lay PVC liner on warm days.
Possible Disadvantages of PVC Liner
PVC pond liner has not only positive properties. Depending on the quality, the liner emits odors into the water in the first few days. It is advisable to introduce fish into the pond two weeks after laying and filling it to avoid endangering them. PVC liner has other unfavorable properties:
- Critical environmental impact
- Disposal of old PVC liner is ecologically questionable
- Lower-quality liner releases plasticizers into the water
- Lower-quality PVC liner is harmful to plants and animals in the water
- PVC liner may have limited durability if plasticizers evaporate and the liner becomes brittle
- Once plasticizers have evaporated, repairs can be challenging
Depending on the quality and weather conditions, PVC liner can become brittle after two to three years, making it difficult or impossible to repair. Folds during installation increase the risk of damage during pond work.
PE Pond Liner: More Environmentally Friendly than PVC Liner
PE pond liner is more environmentally friendly than PVC liner and has similar good properties. It is compatible with fish and plants in the pond. The environmental compatibility of PE liner is mainly due to its better biodegradability compared to PVC liner. The liner is stable but stiff, making it difficult to install. It is suitable for small garden ponds and round or oval shapes. PE liner is more expensive than PVC liner but is more resistant to sunlight and longer-lasting than PVC liner.
PE liner sheets cannot be cold-bonded. Repairs are difficult or impossible. Only with hot air or adhesive tape can the sheets be joined, but adhesive tape often does not seal tightly enough. PE liner is best laid in one piece to avoid seams that can become leaky over time. Even repaired and patched areas can lead to such problems. PE liner is available in thicknesses of 0.5 and 1.0 millimeters.
EPDM Pond Liner: Synthetic Rubber with Excellent Properties
EPDM, a synthetic rubber, is a relatively new material for pond liners. Since this material can be processed excellently, it is also suitable for large garden ponds and swimming ponds. The material is stretchable and tear-resistant, making it possible to lay the liner even on cooler days. Another advantage is that this material is insensitive to UV radiation. The liner is not affected if water evaporates on hot days and part of the liner is exposed to the sun. The liner is also resistant to cold and heat. EPDM pond liner is quite resilient and, therefore, suitable for ponds with a rocky base. Due to its robustness and high stability, this rubber liner is also suitable for greater depths. EPDM liner is also environmentally friendly and harmless to plants, fish, and other animals in your pond. Repairs are easy with a special adhesive and patches made of EPDM liner. However, a disadvantage of this high-quality liner is the higher price compared to PVC or PE liner.
The Key Features of EPDM Pond Liner
EPDM pond liner has many good properties. An outstanding advantage is the long lifespan, which can be up to 50 years. Some manufacturers offer a 20-year warranty. Another good property is the high stretchability. Even at low temperatures, incredible stretchability of up to 300 percent can be achieved. The liner is offered as rolled material with a width of up to 15 meters and a length of up to 61 meters. Due to its enormous stretchability, even large ponds can be laid seamlessly. EPDM liner is also ozone-resistant.
Choosing the Right Thickness for the Pond Liner
If you want to buy a garden pond liner, you should pay attention to the right thickness. As a rule of thumb, the liner should be thicker the larger and deeper your pond is. It also depends on the substrate. For a rocky base, you should buy correspondingly thick liner. If the soil quality is problematic, you should use pond liner fabric in addition to the liner and apply a layer of sand at least 5 centimeters thick to the base. The best thickness is 1.5 millimeters for the liner. For ponds with a depth of up to 160 centimeters, a liner with a thickness of one millimeter can already be used.
Pond liners are available in PVC, PE, and EPDM. PVC is inexpensive and relatively easy to work with but has a poor environmental record. PE has a better environmental record but is stiff and challenging to work with. Synthetic rubber EPDM has the best properties, being environmentally friendly and easy to install. It is stretchable and robust. The downside is the higher price. The ideal thickness is 1.5 millimeters.