POLYTHENE POND LINERS
Both Butyl and Xavan have superseded polythene and although seen as a less costly alternative to these, we would not recommend it as a pond liner.
We suggest that it only be used to construct a temporary holding pond.
When exposed to the weather, polythene becomes brittle and is subject to deterioration from exposure from U.V (Sunlight).
BUTYL POND LINERS
Butyl is still the most common Pond liner and comes in various thicknesses.
One must be sure to select the correct thickness to suit the size of the pond.
A pond up to 102 metres a •5mm thick liner will be sufficient.
For a pond 202 metres you will need 1mm thick liner and over this 1•5mm thick.
A point to consider is that the thicker the liner the harder it is to fold or pleat into fancy shapes and, in cold weather, even a •5mm liner will require warming, so if you decide on Butyl keep your design as simple as possible.
XAVAN POND LINERS
Xavan is a more recent pond lining material marketed under the trade name of PONDTEX® and there is just one thickness - 0.5mm, this being suitable for any size of pond up to 4.52 metres. The liner is therefore much lighter to handle. Being only 0.5mm thick it is very easy to make neat folds or pleats if required even in cold weather and sections can be joined together with a purpose-made tape.
It is claimed to be three times more tear resistant than Butyl, it will not rot,
is said to have a U.V resistance 6 to 7 times that of any other liner and carries a 25 year guarantee.
However the most amazing quality of this material is that it can be nailed to a supporting structure without leaking. We would however advise the use of galvanised nails.
CALCULATING AMOUNT OF MATERIALS REQUIRED
The following is the formula to make sure you buy enough liner material for your proposed pond:
LINER LENGTH = Proposed pond length + twice maximum depth + 600mm
LINER WIDTH = Proposed pond width + twice maximum depth + 600mm
The extra 600mm on each dimension gives you enough 'overlap' to hide under pondside paving stones, rocks or even turf.
LINER GLUE: To glue sections of Butyl liner together you require 50grams of liner glue for every metre of liner seam.
LINER TAPE: Measure the seams and purchase the required roll of Pondtex® tape required and remember you must tape both sides.
© FBAS 2004 RCM/RDE Pond Care Sheet 1 1/1