If you are in the process of creating a garden pond you will have of course to buy a pond liner. Pond liners come in different materials like Epalyn and Butyl but have one thing in common – they have to prevent water loss into the surrounding earth so must be installed properly.

One of the first problems you will face when you buy your liner is working out how much liner material you will need for your pond. The quick calculation below may help with your pond liner purchase:

Pond liner calculation

The first thing you need to do is measure the depth of your pond in feet. Double this figure and add 2 feet to get a 1 foot overlap on the side of the pond. Add this calculated figure to both the measured width and length of the pond and you have your final figure.

If that seems a little confusing we have a worked example so you can see how it works.

You have dug your pond and it measures 8 feet long x 4 feet wide x 4 feet deep. So following the above, 4’deep x 2 = 8’ + 2’ overlap = 10’. Then add this 10’ to your length of 8’ = 18’. Then add the 10’ to your width of 4’ = 14’. That means you need a liner measuring 18’ x 14’. Voila