Biodiversity Net Gain (BNG) is a way of creating and improving natural habitats.
BNG makes sure development has a positive impact (net gain) on biodiversity.
In England, BNG is a statutory requirement under the Environment Act 2021. Developers must deliver at least a 10% increase in biodiversity. This means a development will result in more, or better quality, natural habitats.
Some developments are exempt from BNG. View BNG exemptions on the GOV.UK website.
You can find out more about BNG in:
Measuring biodiversity
BNG is measured in standardised units.
This is for all types of habitats, such as grassland, woods and lakes.
A habitat will contain different biodiversity units depending on things like its:
- size
- quality
- location
- type.
Biodiversity units can be lost through development. Units can also be gained through development with work to create and improve habitats.
Find out more about calculating biodiversity with the statutory biodiversity metric on the GOV.UK website.
Submitting a planning application
If you’re submitting a planning application, you must provide certain information about BNG.
The government has set minimum requirements. We may also seek further information before deciding on a planning application. You should engage with us as early as possible through our pre-application advice service.
The government’s minimum requirements are:
- a statement on whether you believe granted planning permission would be subject to biodiversity net gain
- the pre-development biodiversity value of the habitat (on the date of application or an earlier date). This must show the calculations and calculation tool used, including publication date and version
- where you wish to use an earlier date, the proposed earlier date and the reasons for proposing that date
- a statement confirming whether the biodiversity value of the habitat is lower on the date of application (or an earlier date) because of activities. This must include supporting evidence if degradation has taken place
- a description of any irreplaceable habitat on the land the application relates to (that exists on the date of application or an earlier date)
- a plan for the existing habitat (on the date of application or an earlier date). This should be drawn to scale, show the direction of North and include any irreplaceable habitat.
Exemption under self-build and custom housebuilding
For self-build or custom housebuilding you need to complete our form.
This will help us understand if you meet the legal definition and are exempt from BNG.
Complete our self-build or custom housebuilding form
You must submit this form as part of your planning application.