How to Measure for a Custom Size Pond Liner

When building a pond, getting the correct size liner is essential to get the job done right. At Advance Landscape Systems, we custom make pond liners from a single piece of high-quality polypropylene (Aquamark) or polyethylene (HydraFlex or HydraFlex Pro), and use plastic welding if a wider size is required. This gives you a strong, seamless, high-quality liner.

Here’s how to accurately measure your pond so we can supply the right sized liner for your project.

Measure the Width

Using a measuring tape, start at one side of your pond and stretch it across to the other. Let the tape sink all the way to the bottom, following the shape of the sides. Make sure your total width includes the depth on both sides.

Measure the Length

Repeat the same process for the length of your pond, again measuring from one end to the other and including the depth on both sides.

Don’t Forget the Extra Material

Once you have your width and length measurements (including depth), you will need to add 1 metre to each side. This means you should add a total of 2 metres to both the width and the length.

This extra material allows you to secure the liner properly around the edges of the pond, whether you are using stones, a trench, or another anchoring method.

Example Calculation

Let’s say your pond measures:

• 4 metres wide, with 40 centimetres of depth on each side
• 5 metres long, with 40 centimetres of depth at each end

Your liner size would be calculated like this:
Length: 5m + 0.4m + 0.4m + 2m = 11.6 metres
Width: 4m + 0.4m + 0.4m + 2m = 6.8 metres

Total area required:
11.6m × 6.8m = 78.88 square metres

It is always best to round up, so for this example you would order 79 square metres.

What If My Pond Has Sloped Sides?

If the sides of your pond slope gently down to the bottom rather than dropping vertically, you may not need as much material. However, we recommend allowing for the full size regardless. It is best to have a little extra than to find yourself short during installation.

Ready to Order?

Visit our Pond Liner product page, choose your preferred liner, then enter your required square meterage in the quantity box. In the example above, that would be 79 square meters.

If you need help with your measurements or want to discuss your project further, please call our Customer Care team on 0800 600 789. We’re here to help.