Firestone EPDM Pond Liner Review: The Roofing Rubber Question

Pre-cut, boxed, fish friendly, and specified with almost nothing else stated.

The verdict: Buy it if you want a pre-cut 15 by 20 sheet of 45-mil EPDM from the best known name in the material, at a lower price than most pond branded liners. Skip it if you need documentation, warranty terms or certification stated, because this listing gives dimensions and material and little else.

Specifications

Specifications above come from Firestone's published product specifications. Treat pricing as approximate, since Amazon pricing moves.

What it does well

• Forty five mil EPDM is the standard specification for pond liners and this is the manufacturer most associated with it.
• Pre-cut and boxed, so there is no waiting on a roll to be cut and no risk of a mismeasured order at the counter.
• EPDM has no plasticisers, so it stays flexible for decades rather than going brittle at the folds like PVC.
• It conforms to shelves, ledges and irregular shapes, which is what you buy a liner rather than a preformed shell for.
• Three hundred square feet covers a substantial pond, a stream or both.

Where it falls short

• The listing states material, dimensions and fish friendliness and little else. Certification bodies and warranty terms are not given, so if documentation matters to you, buy a liner that states it.
• Pond grade and roofing grade EPDM are not automatically the same product. Roofing membranes can carry additives not intended for fish, so confirm you are buying the pond specification rather than assuming.
• Underlayment is not included and is not optional. Stones and roots find liners from below over years.
• Once cut it cannot be returned, and a 15 by 20 sheet with a deep pond does not build as large a pond as people assume.
• It is heavy and awkward to position. Lay it out in the sun to soften and get help before dragging it into a hole.

What owners report

Firestone EPDM has a long track record in ponds and owner reports going back many years describe liners still supple and leak free. The recurring caution across the pond community is the roofing versus pond grade distinction, which is why the pond specification exists as a separate product line. Installation damage rather than in-service failure is the dominant reported problem, and it almost always involves a stone left under the liner.

Get the sheet size right before ordering with the pond liner calculator, which accounts for the depth being subtracted twice and for the edge overlap. The rigid versus flexible choice is covered at EPDM liner vs preformed pond, and pond volume calculator turns the finished dig into gallons for stocking and filtration.

Who it suits

• Custom shaped ponds with shelves, ledges and curves.
• Buyers who want a known EPDM brand at a lower price than pond branded liners.
• Streams and waterfall runs, where a single continuous sheet avoids seams.
• Anyone replacing a failed PVC liner and wanting a material that will not repeat the failure.

Who should skip it

• Buyers who need stated warranty terms and certification, better served by a liner that publishes them.
• Small ponds under a few hundred gallons, where a preformed shell is faster.
• Anyone not also buying underlayment.

Alternatives worth considering

Keep reading

• EPDM liner vs preformed pond
• Koi pond vs water garden
• Pond liner calculator
• Best pond liners
• Lifeguard EPDM pond liner review
• Simply Ponds 2100 kit review

This review draws on published specifications, manufacturer figures and the consensus of verified owner reviews. We have not tested this product ourselves, and we say so rather than implying otherwise. As an Amazon Associate we earn from qualifying purchases.