Biodiversity Net Gain (BNG)
BNG is a system brought in by DEFRA in order to increase biodiversity within a nature-depleted UK by increasing biodiversity by at least 10% across most development projects
BNG in 2026
The BNG guidelines are currently under review, with certain sites likely to become exempt from BNG.
The government website will update following any changes to the list of exemptions.
Why are BNG surveys carried out?
BNG is a scheme brought in by DEFRA in 2019. It aims to uplift biodiversity by at least 10% for most development projects, through a framework that measures biodiversity and works out what needs to be done to gain 10%. Most developments will need to have a minimum increase in BNG by 10%, with the exact increase being decided by your respective local planning authority (LPA).
The Statutory Biodiversity Metric is used to measure BNG. This is a calculation that takes into account the habitat size, condition, distinctiveness, and strategic significance.
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When do I need to have a BNG survey?
All developments, which do not fall within the government list of exemptions, are required to be compliant with BNG guidelines.
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This is a phase 1 survey and is undertaken alongside a Preliminary Ecological Appraisal (PEA).
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If a river or watercourse is present on site, it may be that a river condition assessment is required.
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What does Abrehart Ecology offer?
At Abrehart Ecology, we offer professional, skilled, and efficient BNG work. We are a pioneering ecology consultancy, adopting BNG in the early stages of its formation. We carry out all BNG work in-house, from Site work to mapping and calculations, with our team of skilled ecologists and GIS experts.
Further information about BNG can be found here.