Biodiversity Net Gain

Qualifying developments will have to demonstrate, and then deliver, measurable net gains for biodiversity which must be secured, managed, and monitored.

The exact requirements, and methods are different for different categories of application.

The requirement for biodiversity net gain doesn’t alter existing requirements and protections for the natural environment such as protecting important habitats and species. These must be achieved alongside providing BNG.

What BNG information to submit with your planning application

All applications for major development will have to meet new biodiversity requirements. From April 2024 all planning applications for new development (excluding works to domestic properties) will have to meet new biodiversity requirements.

When submitting a planning application (that requires BNG information) you must provide the following for your application to be validated (National Validation Guidance):

  • A statement as to whether the applicant believes that planning permission would be subject to the biodiversity gain condition.
  • The pre-development biodiversity value of the onsite habitat on the date of application (or an earlier date), including the completed metric calculation.

Where the applicant wishes to use an earlier date, they must detail the proposed earlier date and the reasons for proposing that date.

  • A statement confirming whether the value of the onsite habitat is lower on the date of application (or the earlier date) because of the carrying on of activities (‘degradation’), as the value will be taken from before degradation.
  • A description of any irreplaceable habitat (as set out in the regulations) on the land to which the application relates.
  • A plan showing onsite habitat existing on the date of application (or and earlier date), including any irreplaceable habitat.
  • A statutory biodiversity metric . Please note we can only accept these in excel format (.xls) and it must include the date of the assessment, details of the assessor and whether the applicant is requesting permission to purchase statutory biodiversity credits, of if Rule 4 of the metric has been instigated. Guidance can be found on the GOV.UK website .

Without this information your application will be invalidated and returned. The Planning Portal has updated their forms to include the requirement to submit the above info for relevant applications.

Other Advice

  • Applications that are applicable must be accompanied by the ‘statutory metric’, (i.e., metric 4.0 onwards) not previous versions.
  • If a development submitted prior to 12 February 2024 for major developments and April 2024 for non-major developments did not qualify for BNG, and they submit a S73 application which would make them qualify, they are not bound by the new statutory rules.
  • The metric needs to be completed by a competent person – the level of competency is defined in the metric user guide .
  • The metric does not override existing protections and existing professional best practice still applies.
  • The metric is not a complex ecological model and may not be able to represent every feature of a site, it offers a proxy for biodiversity and is designed to inform decisions.
  • If the watercourse part of the metric is needed/completed, the professional completing this will need to have passed the watercourse metric course - find out more.

Minor planning applications

From April 2024 all planning applications for new development (excluding works to domestic properties) will have to meet new biodiversity requirements.

Minor planning applications are expected to demonstrate no net loss, and appropriate net gain, using the latest DEFRA Small Sites metric (or agreed equivalent) - from April 2024.

Further information on qualifying criteria is due to be published by the government prior to this requirement applying.

Developments exempt from BNG regulations:

  • Small sites, 1-9 dwellings / site area less than 0.5hectares / commercial floor space less than 1,000 square meters or site area less than 1hectare;
  • Biodiversity gain sites, developments undertaken for the purpose of fulfilling the BNG planning condition for another development;
  • Householder applications;
  • Self-build and custom build application for fewer than 10 houses;
  • Temporary use of which any habitat lost will be fully reinstated within two years of impact; 
  • Developments below the threshold, meaning the application impacts less than 25 square metres of non-zero distinctiveness habitat, and, less than 5m of hedgerow, and, less than 5m of watercourse, and, does not impact any priority habitat.

Further information can be viewed on the government website.

However, we will still expect such applications to show they have considered biodiversity, and to deliver habitat and species enhancements, as part of a planning application. These could include simple additions, such as the provision of integrated bird and bat boxes, or the use of native and nectar-rich species within landscaping schemes, for example.