Guidance

Biodiversity net gain: exempt developments

A guide to the types of development that will be exempt from the mandatory biodiversity net gain (BNG) requirements.

Applies to England

This draft guidance explains what will apply when BNG becomes mandatory. The guidance will continue to be updated.

The developments listed in this guide are exempt from BNG rules.

Small developments (exempt until April 2024)

Small developments are defined as ‘not major developments’ under the Town and Country Planning (Development Management Procedure) (England) Order 2015.

A small development means:  

  • residential development where the number of dwellings is between 1 and 9, or if this is unknown, the site area is less than 0.5 hectares 
  • commercial development where floor space created is less than 1,000 square metres or total site area is less than 1 hectare 
  • development that is not the winning and working of minerals or the use of land for mineral-working deposits 
  • development that is not waste development

Developments below the threshold

A development that’s below the threshold means that it does not impact a priority habitat and impacts less than: 

  • 25 square metres (5m by 5m) of habitat 
  • 5 metres of linear habitats such as hedgerows

Householder applications

These are applications made by householders as defined within article 2(1) of the Town and Country Planning (Development Management Procedure) (England) Order 2015.

It includes, for example, small projects like home extensions, conservatories or loft conversions

Self-build and custom build applications

An exemption applies to this type of development when all the following conditions apply:   

Biodiversity gain site

Developments undertaken for the purpose of fulfilling the BNG planning condition for another development are exempt.

High speed rail transport network

An exemption applies to any development forming part of, or ancillary to, the high-speed railway transport network, comprising connections between all or any of the places or parts of the transport network specified in section 1(2) of the High Speed Rail (Preparation) Act 2013

Give feedback

Give feedback on this guidance by completing a short survey.

Published 29 November 2023