Planning application forms, biodiversity and validation guidance

Biodiversity Net Gain is mandatory under section 7A of the Town and Country Planning Act 1990 (as inserted by schedule 14 of the Environment Act 2021). All new developments must deliver a biodiversity net gain of 10%.

On 2 April 2024, the legislation changed to:

• include minor as well as major developments
• incorporate the submitting of documents as part of the national validation requirements (where no exemption applies)

Exemptions that existed before 2 April 2024 for minor development no longer apply.

Exemptions

There are some types of development which are exempt and information on exempt developments can be viewed on GOV.UK.

Biodiversity net gain: exempt developments – GOV.UK

Your application for must state the exemption and evidence may be requested.

Applications will only be made valid if they meet the criteria set out in the Biodiversity Net Gain planning application requirements.

For development, which is subject to Biodiversity Net Gain, applicants will also need to provide:

• the pre-development biodiversity value(s), either on the date of application or an earlier proposed date (as appropriate)
• where the applicant wishes to propose an earlier date (than the date of application) for the purposes of calculating pre-development onsite habitat value, the proposed earlier date and the reasons for proposing that date must be provided
• the completed metric calculation tool showing the calculations of the pre-development biodiversity value of the onsite habitat on the date of application (or an earlier date) including the publication date of the biodiversity metric used to calculate that value
• a statement whether the biodiversity value of the onsite habitat is lower on the date of the application (or an earlier date) as a result of activities carried out (known as ‘degradation’), and if degradation has taken place the applicant must provide:
  • a statement to the effect that these activities have been carried out
  • the date immediately before these activities were carried out
  • the pre-development biodiversity value on the date before degradation was carried out
  • the completed metric calculation tool showing the calculations
  • any available supporting evidence of this
• a description of any irreplaceable habitat on the land to which the application relates, that exists on the date of application, (or proposed earlier date); and 
• plan(s), drawn to an identified scale and showing the direction of North, showing onsite habitat existing on the date of application (or an earlier date), including any irreplaceable habitat (if applicable)

These new requirements are provided for in the available updated planning application forms (GOV.UK).

Further guidance is available here: Biodiversity Net Gain planning practice guidance (GOV.UK).

For those who are not already engaged, the Planning Advisory Service (PAS) offers advice, support and training on planning and service delivery to councils. The PAS niodiversity net gain page is a useful resource and provides answers to some of the most frequently asked questions.