Choosing the right pond liner size is easier than it sounds.
With a few simple measurements, you can figure out the liner size you need before you order.
Why Use EPDM for a Pond?If you’re building a pond or water feature, EPDM pond liner is the right material for the job.
Our 45 mil EPDM pond liners are:
- flexible and easy to work with
- built to handle sun, weather, and temperature swings
- safe for fish, plants, and wildlife
- designed specifically for ponds and water features
Some customers ask whether billboard vinyl can be used as a pond liner. While it may seem similar, EPDM is the better choice when you need a material designed to safely hold water long term.How to Calculate Pond Liner SizeStart by measuring your pond at its:
- longest length
- widest width
- deepest depth
Then use this formula:Liner Length = Pond Length + (2 × Depth) + 1'Liner Width = Pond Width + (2 × Depth) + 1'
The extra 1 foot gives you room to anchor the liner around the edges.
Example:Let’s say your pond will be:
- 10' long
- 5' wide
- 3' deep
Step 1: Double the depth2 × 3' = 6'
Step 2: Add 1' for anchoring6' + 1' = 7'
Step 3: Calculate liner length10' + 7' = 17'
Step 4: Calculate liner width5' + 7' = 12'
For this pond, you would need a liner that is at least 12' x 17'.
Since pond liners are sold in standard sizes, it’s best to round up to the next available size. In this example, a 15' x 20' liner would be the right choice.
What Size Underlayment Should I Order?
If you’re adding underlayment,we recommend ordering the same size underlayment as your pond liner.
For example, if you order a 15' x 20' pond liner, order a 15' x 20' underlayment as well.
Underlayment sits beneath the liner to help protect it from rocks, roots, and rough ground. Using the same size helps make sure the full bottom and sides of the pond are covered.
When in Doubt, Size UpIf your measurements fall between sizes, choose the larger size.A little extra material gives you more room to position and secure everything properly.
Planning for Fish?If you plan to keep fish, we recommend building your pond at least 3 feet deep.That added depth can help protect fish from predators and temperature swings.
