Russetts Development Ltd

A guide to box welded pond liners


Source: Russetts Development Ltd

What are box welded pond liners?

A box welded liner is a prefabricated liner made to the exact specifications you provide to the supplier. You simply measure the dimensions of the hole you need to fill and the liner arrives, pre-made, ready to slot into the hole. Box welded liners tend to be made of either Butyl or EPDM rubber. All of the liner's seams will be fully welded for maximum strength, which means that there are no folds in the liner. Liners can be of any size and shape.

EPDM liners tend to be 1mm thick and Butyl liners are usually 0.75mm thick. Simple liners, such as squares and L-shapes, can be made by the manufacturer from just the required dimensions. More complex designs will require a drawing for them to work from. Very complicated pond liners can be created and installed on site.

What are the advantages of a box welded liner?

Box welded pond liners have several advantages over flat sheet liners. They fit perfectly into the hole you have prepared and eliminate the need for unsightly folds. They can be produced exactly to the dimensions you specify, and are easy and fast to install. EPDM or Butyl rubber liners have a life expectancy of around 40 years but can last much longer.

Box welded liners are also supplied with a lip all the way round the top, known as a flange. This holds the liner securely in place and also provides a nice neat finish to the pond or other water feature. Because, unlike with flat sheet liners, there are no folds in the liner, there is much less chance of bacterial build-up. Folds and ridges can trap debris which then encourages bacteria to grow, which can affect the water quality in the pond. Bacterial build up can be fatal to fish, such as koi carp, and can also make a water feature appear murky and dirty. Welded pond liners are so well sealed that they can even be used in drinking water applications.

Box welded liners are usually supplied with a 25 year warranty. This is usually on the condition that the liner is installed above a protective layer of underlay.

What shapes are best?

Standard shapes such as rectangles, squares, L-shapes and circles work best but any shape is possible. If you are thinking of installing a pond on two or more different levels, such designs are possible but you may wish to reconsider. Different levels within a pond will create a shelf and shelves are notorious for collecting debris which can affect the water quality. The effect of different layers on the water flow within the feature is also hard to predict and can lead to stagnant areas forming. A gradual slope is often better than a step.

If you are a landscape gardener or similar you may wish to order in some stock of ready-made liners in two or three different shapes. You can then offer your customers the choice of several affordable pond options.

For more information visits us at or call +44 (0)870 770 2800.

Customer comments

No comments were found for A guide to box welded pond liners. Be the first to comment!