🐟 Pond Liner Size Calculator
Calculate the exact liner dimensions, area, and weight for any pond shape and depth
| Material | Thickness | Weight (lb/ft²) | Lifespan | UV Resistance |
|---|---|---|---|---|
| EPDM Rubber | 45 mil | 0.33 | 20–30 yrs | Excellent |
| PVC | 20 mil | 0.13 | 10–15 yrs | Moderate |
| RPE | 36 mil | 0.10 | 20–40 yrs | Excellent |
| HDPE | 30 mil | 0.16 | 25–35 yrs | Excellent |
| Butyl Rubber | 60 mil | 0.42 | 25–50 yrs | Excellent |
| Underlayment | 8 oz | 0.05 | N/A (protective) | N/A |
| Pond Type | Dimensions (ft) | Depth (ft) | Liner Size Needed (ft) |
|---|---|---|---|
| Small Fountain | 5 × 3 | 1 | 11 × 9 |
| Garden Pond | 6 × 4 | 2 | 14 × 12 |
| Koi Starter | 8 × 5 | 3 | 18 × 15 |
| Water Garden | 10 × 8 | 3 | 20 × 18 |
| Medium Koi | 12 × 10 | 4 | 24 × 22 |
| Large Koi | 15 × 12 | 5 | 29 × 26 |
| Natural Pond | 20 × 15 | 4 | 32 × 27 |
| Farm Pond | 25 × 20 | 5 | 39 × 34 |
| Max Depth | Min Overlap | Recommended Overlap | Notes |
|---|---|---|---|
| 1 ft (0.3 m) | 1 ft | 1.5 ft | Shallow fountain or bog garden |
| 2 ft (0.6 m) | 1.5 ft | 2 ft | Standard garden pond |
| 3 ft (0.9 m) | 2 ft | 2 ft | Most koi and water gardens |
| 4 ft (1.2 m) | 2 ft | 2.5 ft | Deep koi pond, extra anchoring |
| 5+ ft (1.5+ m) | 2.5 ft | 3 ft | Large or farm ponds |
Count the right Size of the Pond Liner for a pool can seem hard, but simplicity lies in a formula that answers for almost all pools. One simply takes the maximum measures of length, width and depth, and puts them in easy math. The math itself is this: twice the depth plus the length and twice the depth plus the width.
Many versions of that method include extra two feet for every side, to ensure good coverage. Like this one gets the final Size: (length plus twice depth plus two) multiplied by (width plus twice depth plus two).
How to Choose the Right Pond Liner Size
Here a sample to explain. Assume that pool measures 10 feet in length, 5 feet in width and 3 feet in depth. According to the method, the Pond Liner needs to be at least 17 feet long and 12 feet wide.
In another case, with 10 feet long, 5 feet wide and 2.5 feet deep, one again arrives at around 17 by 12 feet. The most close available Size commonly is 15 by 20, because Pond Liners usually sell in steps of 5 feet.
When a pool has different depths, always base on the maximum depth. Like this one ensures enough material to cover everything well. The deepest area decides, how much extra Pond Liner is needed to go down and upward along both banks.
It is best too end the digging before ordering the Pond Liner, because ordered Size can not be exchanged usually.
A 15-by-15-foot Pond Liner works well for a 10-by-10 pool with around 2 feet depth. If someone builds a 9-by-9 pool with maximum depth of 2 feet, he counts the needs using that 2-foot value. The method works surprisingly for round, shaped or naturally organic pools, not only for rectangles.
About the material, 45-mil EPDM-rubber stays the most popular choice for most pools. It resists fish, UV-rays and bends quite a lot to adapt to built banks and curves. EPDM Pond Liners sell in exactly cut Size up to 50 by 100 feet.
Buy discounted Pond Liner never worth the risk. RPE Pond Liner costs less, but it does not bend as well and lacks flexibility, so it suits more for simple forms without many banks and curves.
Depth matters also for the fish. Big fish need at least 90 centimetres depth. A more natural pool with little fish works at around 50 centimetres.
Plan at least 4 feet depth in part of the pool, to help fish escape predators and bad weather. Do not forget to add extra width to the Pond Liner, if you build a fall, because the banks need enough material to hold the water flow.
Online calculators for pond Pond Liner simplify all that. Just enter the Size of the pool, andthe tool will compute the volume and the needed Size of the Pond Liner.
