The five bands
- Very Low (0): developed / sealed surface, bare ground.
- Low (2): modified grassland, mixed scrub, arable field margins.
- Medium (4): other neutral grassland, lowland mixed deciduous woodland (planted), modified hedgerows.
- High (6): lowland meadow, lowland calcareous grassland, native species-rich hedgerow, ancient woodland (where not irreplaceable).
- Very High (8): lowland fen, blanket bog, coastal saltmarsh, chalk rivers, irreplaceable habitats.
The full JP039 habitat list runs to ~130 entries; the technical annex carries the canonical lookup.[S1]
How distinctiveness multiplies vs condition
Distinctiveness is fixed by habitat type and cannot be improved through condition uplift; condition is the variable a developer can influence post-implementation. A poor-condition lowland meadow (6 x 1 = 6) still scores higher per hectare than a good-condition modified grassland (2 x 3 = 6); the bands compound through area.
Worked example
0.5 ha of high-distinctiveness lowland meadow at good condition: 6 x 3 x 0.5 x 1.0 = 9 BU. 0.5 ha of low-distinctiveness modified grassland at moderate condition: 2 x 2 x 0.5 x 1.0 = 2 BU. The same area at different bands produces 4.5x the unit yield. Trading rules require like-for-like or better; losing the lowland meadow cannot be compensated by creating more modified grassland.
JP039 column reference
The canonical lookup sits in the “Habitats” tab of the JP039 spreadsheet; the distinctiveness column is the left-most value column and matches the technical annex tables. Use the current published version; the calculator on this site mirrors v4.0 published 18 May 2024 and refreshed in technical guidance July 2025.[S2]