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BNG comes into effect for small site development

From Tuesday 2nd April 2024, Biodiversity Net Gain (BNG) policy applies to small development sites 

This includes residential development sites no more than a hectare in size with fewer than 10 dwellings and commercial development sites no more than a hectare or 1000 square metres in size. 

While some will remain exempt, BNG will now apply to most development projects in England. 

BNG came into effect for major developments on 12th February and will also apply to nationally significant infrastructure projects (NSIPs) from November 2025. 

Mandated under the Environment Act 2021, BNG is designed to ensure that any habitats damaged as a result of development are adequately replaced, plus an additional 10%. 

In order to secure planning permission, development projects impacted by BNG policy will have to demonstrate how they will achieve a 10% net gain in biodiversity value by submitting a biodiversity gain plan to the local planning authority (LPA). This will include long-term monitoring and reporting plans.

If they’re unable to deliver this at the site of the development itself, developers can purchase off-site Biodiversity Units to compensate. These Units will be generated via Habitat Banks designed to restore biodiversity.

How can small sites deliver BNG?

Small development projects are likely to have a correspondingly small BNG requirement. They may only need to account for a fraction of a Biodiversity Unit and, due to their limited space, may face challenges delivering this on-site. 

Third-party off-site BNG providers will therefore play a key role in helping to facilitate small development projects, particularly providers who are able to cater for fractional Biodiversity Unit requests. 

SME developers may have concerns that they will have to purchase entire Biodiversity Units and, depending on the habitat type, these can be costly.  

As such, Environment Bank has a flexible, cost-effective system in place to enable us to satisfy Unit requests between 0-1. This will enable developers working with us to meet their exact BNG requirements, even if they require less than a whole Unit.

Environment Bank has played an important role in BNG policy and currently has one of England’s broadest networks of BNG Habitat Banks. From these high-quality nature restoration sites, we can provide Biodiversity Units for small development projects nationwide. In a single transaction, we can remove all long-term liability for habitat monitoring and reporting from the developer.

Our team of RTPI planners are here to provide support and guidance with off-site BNG options. We have already helped to unlock projects by enabling developers to meet their BNG requirements and unlock projects. 

Follow Defra’s step-by-step guide for developers to learn more. Contact us to discuss off-site Biodiversity Units for your project.

Find out the cost and availability of Biodiversity Units for your development