{
  "spec": "https://entitymap.org/spec/v1.0",
  "site": "https://bestpondliner.co.uk",
  "generated": "2026-07-30",
  "entities": [
    {
      "id": "best-pond-liner",
      "type": "Organization",
      "name": "Best Pond Liner",
      "description": "Independent UK publisher covering pond liners: material comparisons, sizing tools and installation guides. Publishes as a brand rather than under a personal byline.",
      "url": "https://bestpondliner.co.uk/",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "pond-liner",
      "type": "Thing",
      "name": "Pond liner",
      "description": "An impermeable membrane or shell used to retain water in an artificial pond. The parent concept for everything else on this site.",
      "sameAs": "https://en.wikipedia.org/wiki/Pond_liner",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/materials/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "epdm-rubber",
      "type": "Thing",
      "name": "EPDM rubber",
      "description": "Synthetic rubber, the usual choice for UK garden ponds. Sold at 0.75mm and 1.02mm. Firestone publishes a 20 year warranty on its PondGard grade, excluding punctures. Roofing-grade EPDM is a different product and is not fish safe.",
      "sameAs": "https://en.wikipedia.org/wiki/EPDM_rubber",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/materials/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "butyl-rubber",
      "type": "Thing",
      "name": "Butyl rubber",
      "description": "The older flexible rubber lining, typically 0.75mm. Slightly more forgiving than EPDM around complex organic shapes, which suits wildlife ponds.",
      "sameAs": "https://en.wikipedia.org/wiki/Butyl_rubber",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/materials/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "pvc",
      "type": "Thing",
      "name": "Polyvinyl chloride",
      "description": "The budget lining material, typically 0.5mm. Cheaper and lighter than rubber but least stable under ultraviolet exposure, so the strip above the water line degrades first.",
      "sameAs": "https://en.wikipedia.org/wiki/Polyvinyl_chloride",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/materials/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "hdpe",
      "type": "Thing",
      "name": "High-density polyethylene",
      "description": "Stiffer than rubber and used for large or commercial installations, often welded on site rather than laid as a single sheet.",
      "sameAs": "https://en.wikipedia.org/wiki/High-density_polyethylene",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/materials/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "ldpe",
      "type": "Thing",
      "name": "Low-density polyethylene",
      "description": "More flexible and cheaper than HDPE but less hard-wearing. Not the natural choice for a garden pond.",
      "sameAs": "https://en.wikipedia.org/wiki/Low-density_polyethylene",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/materials/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "bentonite",
      "type": "Thing",
      "name": "Bentonite clay",
      "description": "A natural sealing clay that waterproofs by swelling when wet. Used for large informal ponds and dependent on suitable ground conditions, so not a like-for-like alternative to a sheet liner.",
      "sameAs": "https://en.wikipedia.org/wiki/Bentonite",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/materials/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "fibreglass",
      "type": "Thing",
      "name": "Fibreglass",
      "description": "Used for rigid preformed shells. More durable and more expensive than moulded plastic, and suited to permanent formal ponds.",
      "sameAs": "https://en.wikipedia.org/wiki/Fiberglass",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/materials/",
          "confidence": 0.8
        }
      ]
    },
    {
      "id": "geotextile-underlay",
      "type": "Thing",
      "name": "Geotextile pond underlay",
      "description": "A protective fabric layer laid beneath the liner at the same size, guarding against sharp stones and roots. Puncture damage from below is the most common cause of failure and is normally excluded from a manufacturer guarantee.",
      "sameAs": "https://en.wikipedia.org/wiki/Geotextile",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/materials/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "liner-sizing",
      "type": "HowTo",
      "name": "Pond liner sizing",
      "description": "Calculating sheet size by adding twice the maximum depth and twice the edge allowance to both the length and the width of the pond. A free calculator and size chart are published on this site.",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/pond-liner-calculator/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "uv-degradation",
      "type": "Thing",
      "name": "Ultraviolet degradation",
      "description": "Sunlight breaking down liner material over time. The strip above the water line is the only part in direct sun, which is why a liner typically fails at the edge rather than underwater. This is why concealing the edge is a durability measure, not only a cosmetic one.",
      "sameAs": "https://en.wikipedia.org/wiki/Ultraviolet",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/guides/hiding-pond-liner-edges/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "capillary-wicking",
      "type": "Thing",
      "name": "Capillary wicking at a pond edge",
      "description": "Absorbent material such as turf or soil draped over the rim and touching the water siphons it out by capillary action until the level drops below the contact point. Routinely misdiagnosed as a puncture.",
      "sameAs": "https://en.wikipedia.org/wiki/Capillary_action",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/guides/hiding-pond-liner-edges/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "pond-construction",
      "type": "HowTo",
      "name": "Pond construction with a flexible liner",
      "description": "Marking out and levelling, digging with marginal shelves, clearing the excavation, laying underlay, fitting the liner, filling slowly, then trimming and edging in that order.",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/guides/how-to-build-a-pond-with-a-liner/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "edge-concealment",
      "type": "HowTo",
      "name": "Pond edge concealment",
      "description": "Hiding the exposed liner flap using a stone overhang, gravel beach, marginal planting, turf, a bog garden or timber edging.",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/guides/hiding-pond-liner-edges/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "garden-pond",
      "type": "Thing",
      "name": "Garden pond",
      "description": "An ornamental or naturalistic pond in a domestic garden. The default context for everything published here.",
      "sameAs": "https://en.wikipedia.org/wiki/Garden_pond",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/",
          "confidence": 1
        }
      ]
    },
    {
      "id": "wildlife-pond",
      "type": "Thing",
      "name": "Wildlife pond",
      "description": "A pond built to support amphibians, insects and birds, characterised by a shallow beach entry giving access in and out.",
      "sameAs": "https://en.wikipedia.org/wiki/Pond",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/guides/hiding-pond-liner-edges/",
          "confidence": 0.8
        }
      ]
    },
    {
      "id": "koi-pond",
      "type": "Thing",
      "name": "Koi pond",
      "description": "A pond stocked with koi carp, requiring greater depth than a wildlife or ornamental pond and affecting both liner size and edge treatment.",
      "sameAs": "https://en.wikipedia.org/wiki/Koi_pond",
      "evidence": [
        {
          "source": "https://bestpondliner.co.uk/pond-liner-calculator/",
          "confidence": 0.6
        }
      ]
    }
  ]
}