Free Pond Liner Size Calculator - Required Area | Pond Calculator
Free pond liner size calculator. Enter pond dimensions and depth to calculate the required liner size with overhang allowance.
How to Use the Liner Size Calculator
Enter pond length, width, maximum depth, and overhang to calculate the required liner dimensions. Default overhang is 2 ft (about 60 cm) on each side.
Liner formula: Liner Length = Pond Length + (2 × Max Depth) + (2 × Overhang). The same formula applies to width.
EPDM and PVC liners are recommended. When installing over gravel or sharp rocks, use a protective underlay to prevent punctures.
FAQ
How do I calculate the pond liner size I need?
Liner Length = Pond Length + (2 × Max Depth) + (2 × Overhang). Liner Width = Pond Width + (2 × Max Depth) + (2 × Overhang). Use 2 feet (60cm) overhang on each side to anchor the liner securely.
What is the best pond liner material?
EPDM rubber liners are the most popular choice — flexible, UV-resistant, and last 20+ years. PVC liners are cheaper but less durable (10–15 years). HDPE liners are rigid and best for large commercial ponds.
How thick should my pond liner be?
For garden ponds, use 45-mil (1.14mm) EPDM liner minimum. For koi ponds with sharp rocks or heavy fish loads, use 60-mil (1.52mm). Thicker liners resist punctures better and last longer.
Do I need an underlay beneath my pond liner?
Yes, always use a protective underlay (geotextile fabric) beneath your liner. It protects against sharp stones, roots, and ground movement. Without underlay, even small rocks can puncture the liner over time.
How much extra liner should I order?
Order 10–15% extra beyond the calculated size to account for irregular shapes, shelves, and installation errors. It's much cheaper to have extra liner than to run short during installation.