{
  "api": "woodintel",
  "version": "1.0.0",
  "license": "CC BY 4.0 — WoodIntel (woodintel.io)",
  "attribution": "WoodIntel — woodintel.io",
  "generated": "2026-11-03T00:45:30.133Z",
  "count": 14,
  "method": {
    "id": "WI-GAP",
    "version": "1.0.0"
  },
  "note": "Gap score = 0.35 thin record + 0.25 unresolved dissent + 0.20 ageing evidence + 0.20 low evidence score. A high score means the open literature cannot currently settle the claim; it is not a verdict on the claim.",
  "data": [
    {
      "slug": "silicate-surface-treatment-weathering",
      "statement": "Silicate-based surface treatments measurably slow the surface weathering of exterior softwood.",
      "subject": "Silicate treatment",
      "topic": "Surface protection",
      "evidenceScore": null,
      "studyCount": 4,
      "contradicting": 1,
      "lastStudyYear": 2015,
      "gapScore": 88,
      "priority": "critical",
      "question": "A reconciliation study explaining why 1 indexed record disagrees with the current conclusion — differing exposure, method or measure.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 67,
          "weight": 0.35,
          "note": "4 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 100,
          "weight": 0.25,
          "note": "1 of 1 classified records contradict the conclusion."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 100,
          "weight": 0.2,
          "note": "Most recent indexed study: 2015 (11 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 100,
          "weight": 0.2,
          "note": "Insufficient evidence for a score."
        }
      ],
      "url": "https://woodintel.io/evidence/silicate-surface-treatment-weathering"
    },
    {
      "slug": "accelerated-tests-predict-field",
      "statement": "Accelerated laboratory weathering tests reliably predict field performance of exterior wood coatings.",
      "subject": "Test methods",
      "topic": "Methods",
      "evidenceScore": 45,
      "studyCount": 56,
      "contradicting": 3,
      "lastStudyYear": 2024,
      "gapScore": 40,
      "priority": "moderate",
      "question": "A reconciliation study explaining why 3 indexed records disagree with the current conclusion — differing exposure, method or measure.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "56 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 98,
          "weight": 0.25,
          "note": "3 of 4 classified records contradict the conclusion."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 20,
          "weight": 0.2,
          "note": "Most recent indexed study: 2024 (2 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 55,
          "weight": 0.2,
          "note": "Evidence strength 45/100."
        }
      ],
      "url": "https://woodintel.io/evidence/accelerated-tests-predict-field"
    },
    {
      "slug": "detailing-outweighs-durability-class",
      "statement": "Design detailing that keeps water off end grain affects the service life of exterior wood more than moving one EN 350 durability class.",
      "subject": "Detailing",
      "topic": "Service life",
      "evidenceScore": null,
      "studyCount": 53,
      "contradicting": 0,
      "lastStudyYear": 2025,
      "gapScore": 22,
      "priority": "low",
      "question": "Higher-grade evidence on Detailing — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "53 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 0,
          "weight": 0.25,
          "note": "No records classified for or against yet."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 10,
          "weight": 0.2,
          "note": "Most recent indexed study: 2025 (1 year ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 100,
          "weight": 0.2,
          "note": "Insufficient evidence for a score."
        }
      ],
      "url": "https://woodintel.io/evidence/detailing-outweighs-durability-class"
    },
    {
      "slug": "clt-charring-rate-predictability",
      "statement": "Charring rates of cross-laminated timber under standard fire exposure are predictable within the Eurocode 5 design assumptions.",
      "subject": "CLT fire",
      "topic": "Fire",
      "evidenceScore": null,
      "studyCount": 24,
      "contradicting": 0,
      "lastStudyYear": 2026,
      "gapScore": 20,
      "priority": "low",
      "question": "Higher-grade evidence on CLT fire — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "24 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 0,
          "weight": 0.25,
          "note": "No records classified for or against yet."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 0,
          "weight": 0.2,
          "note": "Most recent indexed study: 2026 (0 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 100,
          "weight": 0.2,
          "note": "Insufficient evidence for a score."
        }
      ],
      "url": "https://woodintel.io/evidence/clt-charring-rate-predictability"
    },
    {
      "slug": "acetylation-dimensional-stability",
      "statement": "Acetylation reduces the moisture-driven dimensional movement of wood by more than half relative to the untreated species.",
      "subject": "Acetylation",
      "topic": "Modification",
      "evidenceScore": null,
      "studyCount": 20,
      "contradicting": 0,
      "lastStudyYear": 2026,
      "gapScore": 20,
      "priority": "low",
      "question": "Higher-grade evidence on Acetylation — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "20 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 0,
          "weight": 0.25,
          "note": "No records classified for or against yet."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 0,
          "weight": 0.2,
          "note": "Most recent indexed study: 2026 (0 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 100,
          "weight": 0.2,
          "note": "Insufficient evidence for a score."
        }
      ],
      "url": "https://woodintel.io/evidence/acetylation-dimensional-stability"
    },
    {
      "slug": "mass-timber-hygrothermal-risk",
      "statement": "Mass timber assemblies carry a higher built-in moisture risk during construction than they do in service.",
      "subject": "Mass timber",
      "topic": "Moisture",
      "evidenceScore": null,
      "studyCount": 48,
      "contradicting": 0,
      "lastStudyYear": 2026,
      "gapScore": 20,
      "priority": "low",
      "question": "Higher-grade evidence on Mass timber — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "48 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 0,
          "weight": 0.25,
          "note": "0 of 2 classified records contradict the conclusion."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 0,
          "weight": 0.2,
          "note": "Most recent indexed study: 2026 (0 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 100,
          "weight": 0.2,
          "note": "Insufficient evidence for a score."
        }
      ],
      "url": "https://woodintel.io/evidence/mass-timber-hygrothermal-risk"
    },
    {
      "slug": "coating-maintenance-interval-extends-life",
      "statement": "Regular maintenance of a film-forming coating extends the service life of exterior timber cladding more than the initial coating choice does.",
      "subject": "Coating maintenance",
      "topic": "Maintenance",
      "evidenceScore": null,
      "studyCount": 53,
      "contradicting": 0,
      "lastStudyYear": 2026,
      "gapScore": 20,
      "priority": "low",
      "question": "Higher-grade evidence on Coating maintenance — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "53 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 0,
          "weight": 0.25,
          "note": "No records classified for or against yet."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 0,
          "weight": 0.2,
          "note": "Most recent indexed study: 2026 (0 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 100,
          "weight": 0.2,
          "note": "Insufficient evidence for a score."
        }
      ],
      "url": "https://woodintel.io/evidence/coating-maintenance-interval-extends-life"
    },
    {
      "slug": "untreated-larch-service-life",
      "statement": "Untreated larch cladding reaches a service life comparable to surface-treated softwood in temperate Northern European climates.",
      "subject": "Larch",
      "topic": "Service life",
      "evidenceScore": null,
      "studyCount": 19,
      "contradicting": 0,
      "lastStudyYear": 2026,
      "gapScore": 20,
      "priority": "low",
      "question": "Higher-grade evidence on Larch — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "19 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 0,
          "weight": 0.25,
          "note": "No records classified for or against yet."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 0,
          "weight": 0.2,
          "note": "Most recent indexed study: 2026 (0 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 100,
          "weight": 0.2,
          "note": "Insufficient evidence for a score."
        }
      ],
      "url": "https://woodintel.io/evidence/untreated-larch-service-life"
    },
    {
      "slug": "preservative-treated-pine-use-class-3",
      "statement": "Preservative-treated Scots pine sapwood reaches the intended service life in EN 335 use class 3 exposure.",
      "subject": "Preservative treatment",
      "topic": "Service life",
      "evidenceScore": null,
      "studyCount": 13,
      "contradicting": 0,
      "lastStudyYear": 2026,
      "gapScore": 20,
      "priority": "low",
      "question": "Higher-grade evidence on Preservative treatment — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "13 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 0,
          "weight": 0.25,
          "note": "No records classified for or against yet."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 0,
          "weight": 0.2,
          "note": "Most recent indexed study: 2026 (0 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 100,
          "weight": 0.2,
          "note": "Insufficient evidence for a score."
        }
      ],
      "url": "https://woodintel.io/evidence/preservative-treated-pine-use-class-3"
    },
    {
      "slug": "moisture-content-threshold-decay",
      "statement": "Sustained wood moisture content above 25 percent is the controlling condition for fungal decay initiation in above-ground timber.",
      "subject": "Moisture",
      "topic": "Decay",
      "evidenceScore": null,
      "studyCount": 46,
      "contradicting": 0,
      "lastStudyYear": 2026,
      "gapScore": 20,
      "priority": "low",
      "question": "Higher-grade evidence on Moisture — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "46 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 0,
          "weight": 0.25,
          "note": "0 of 2 classified records contradict the conclusion."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 0,
          "weight": 0.2,
          "note": "Most recent indexed study: 2026 (0 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 100,
          "weight": 0.2,
          "note": "Insufficient evidence for a score."
        }
      ],
      "url": "https://woodintel.io/evidence/moisture-content-threshold-decay"
    },
    {
      "slug": "timber-biogenic-carbon-storage",
      "statement": "Long-lived timber construction products deliver a net biogenic carbon storage benefit over the building service life.",
      "subject": "Carbon",
      "topic": "Sustainability",
      "evidenceScore": 58,
      "studyCount": 53,
      "contradicting": 2,
      "lastStudyYear": 2026,
      "gapScore": 13,
      "priority": "low",
      "question": "Higher-grade evidence on Carbon — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "53 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 17,
          "weight": 0.25,
          "note": "2 of 15 classified records contradict the conclusion."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 0,
          "weight": 0.2,
          "note": "Most recent indexed study: 2026 (0 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 42,
          "weight": 0.2,
          "note": "Evidence strength 58/100."
        }
      ],
      "url": "https://woodintel.io/evidence/timber-biogenic-carbon-storage"
    },
    {
      "slug": "thermal-modification-durability",
      "statement": "Thermal modification measurably increases the decay resistance of softwood in above-ground exterior use.",
      "subject": "Thermal modification",
      "topic": "Modification",
      "evidenceScore": 52,
      "studyCount": 32,
      "contradicting": 1,
      "lastStudyYear": 2026,
      "gapScore": 12,
      "priority": "low",
      "question": "Higher-grade evidence on Thermal modification — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "32 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 9,
          "weight": 0.25,
          "note": "1 of 15 classified records contradict the conclusion."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 0,
          "weight": 0.2,
          "note": "Most recent indexed study: 2026 (0 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 48,
          "weight": 0.2,
          "note": "Evidence strength 52/100."
        }
      ],
      "url": "https://woodintel.io/evidence/thermal-modification-durability"
    },
    {
      "slug": "scheffer-index-decay-prediction",
      "statement": "The Scheffer climate index is a reliable predictor of above-ground decay hazard across climate zones.",
      "subject": "Decay modelling",
      "topic": "Modelling",
      "evidenceScore": 45,
      "studyCount": 41,
      "contradicting": 0,
      "lastStudyYear": 2026,
      "gapScore": 11,
      "priority": "low",
      "question": "Higher-grade evidence on Decay modelling — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "41 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 0,
          "weight": 0.25,
          "note": "0 of 3 classified records contradict the conclusion."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 0,
          "weight": 0.2,
          "note": "Most recent indexed study: 2026 (0 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 55,
          "weight": 0.2,
          "note": "Evidence strength 45/100."
        }
      ],
      "url": "https://woodintel.io/evidence/scheffer-index-decay-prediction"
    },
    {
      "slug": "wood-carbon-substitution-benefit",
      "statement": "Substituting timber for mineral structural materials reduces the cradle-to-gate greenhouse gas emissions of a building.",
      "subject": "Substitution",
      "topic": "Sustainability",
      "evidenceScore": 55,
      "studyCount": 65,
      "contradicting": 0,
      "lastStudyYear": 2026,
      "gapScore": 9,
      "priority": "low",
      "question": "Higher-grade evidence on Substitution — controlled or long-run field work rather than the present mix.",
      "factors": [
        {
          "key": "thinness",
          "label": "Thin record",
          "value": 0,
          "weight": 0.35,
          "note": "65 indexed studies against a reference of 12."
        },
        {
          "key": "dissent",
          "label": "Unresolved dissent",
          "value": 0,
          "weight": 0.25,
          "note": "0 of 12 classified records contradict the conclusion."
        },
        {
          "key": "staleness",
          "label": "Ageing evidence",
          "value": 0,
          "weight": 0.2,
          "note": "Most recent indexed study: 2026 (0 years ago)."
        },
        {
          "key": "softness",
          "label": "Low evidence score",
          "value": 45,
          "weight": 0.2,
          "note": "Evidence strength 55/100."
        }
      ],
      "url": "https://woodintel.io/evidence/wood-carbon-substitution-benefit"
    }
  ]
}