BIODIVERSITY METRIC

Biodiversity metric guide.

How the statutory biodiversity metric turns habitat baseline and target condition into BNG unit calculations.

BNG RESOURCE · UPDATED 26 JULY 2026

Decision-ready guidance for England's BNG market.

The metric starts with what habitat exists before intervention, including type, size or length, condition and distinctiveness.

Planned creation or enhancement is assessed against target type, condition and deliverability.

Habitats that take longer to reach target condition are adjusted for temporal risk.

More difficult interventions may carry a risk adjustment because delivery is less certain.

Location and local strategy can affect the score and market usefulness of the units.

Developers cannot always substitute one habitat type for another; trading rules affect what units can satisfy a shortfall.

Commercial value also depends on legal security, demand, timing, costs and buyer confidence.

Metric calculations should be supported by surveys, maps, condition assessments and a credible HMMP.

COMMON QUESTIONS

No. The metric calculates units; market value also depends on demand, cost, risk, timing and scarcity.

Yes. Better surveys, design changes, legal constraints or delivery assumptions can change the output.

Suitably qualified ecological professionals should prepare or review the metric evidence.

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