What is Biodiversity Net Gain? A Guide for Planning Applications

Biodiversity Net Gain (BNG) is a mandatory requirement for many planning applications in England. It ensures that development projects leave the natural environment in a better state than before by improving habitats and increasing biodiversity. With the Environment Act 2021 making BNG a legal requirement from January 2024, developers, planning consultants, and landowners must understand how to integrate BNG into their projects.

This guide explains what BNG is, why it matters, and how to comply with the BNG 10% uplift requirement for planning applications.

What is Biodiversity Net Gain (BNG)?

Biodiversity Net Gain is an approach to development that ensures measurable improvements in natural habitats and ecosystems. It follows the principle of:

✅ Avoiding biodiversity loss where possible

✅ Minimising impacts to the environment

✅ Enhancing biodiversity beyond pre-development conditions

Under BNG policy, developers must demonstrate that they are delivering at least a 10% net gain in biodiversity through on-site or off-site measures.

Why Does BNG Matter?

BNG is designed to reverse biodiversity decline and ensure that development projects contribute to ecological resilience. Key benefits include:

🌱 Legal Compliance – As of 2024, BNG is legally required for most planning applications.🌍 Environmental Protection – Helps maintain and restore natural habitats.

🏡 Planning Approval – Meeting BNG requirements increases the likelihood of planning permission success.

💰 Financial Incentives – Landowners can sell BNG credits through habitat banking schemes.

How to Achieve BNG in Planning Applications

BNG must be measured using the Biodiversity Metric developed by Natural England. The process involves:

1️⃣ Baseline Habitat Assessment – A Preliminary Ecological Appraisal (PEA) is conducted to assess existing biodiversity value.

2️⃣ BNG Calculation – Using the Biodiversity Metric, developers calculate the current habitat value and the improvements needed.

3️⃣ On-Site vs. Off-Site Delivery – Developers must decide whether to achieve BNG through on-site habitat creation or by buying BNG credits.

4️⃣ BNG Plan Submission – A Biodiversity Gain Plan (BGP) must be submitted as part of the planning application.

5️⃣ Long-Term Monitoring – BNG must be maintained for at least 30 years, ensuring habitat success.

What Type of Developments Require BNG?

BNG applies to most new housing, commercial, and infrastructure developments, including:

• Residential housing developments

• Industrial and commercial sites

• Road and transport projects

• Mixed-use developments

• Large-scale infrastructure projects

💡 Exemptions: Some developments, such as small-scale self-build homes and permitted developments, may not require BNG.

On-Site vs. Off-Site BNG Solutions

BNG Approach	Description	Example
On-Site BNG	Developers create new habitats within their project boundary.	Wildflower meadows, new hedgerows, woodland planting.
Off-Site BNG	BNG is delivered outside the development site through habitat banks or landowners.	Purchasing biodiversity credits from a landowner.
Statutory Credits	Developers buy government-regulated biodiversity credits as a last resort.	Used if no on-site or off-site options are available.

BNG & Local Planning Authorities (LPAs)

Local councils are responsible for enforcing BNG requirements. Developers must submit a Biodiversity Gain Plan, outlining:

✅ How BNG will be achieved (on-site, off-site, or credits)

✅ Long-term management and monitoring plans

✅ Evidence of measurable net gain using the Biodiversity Metric

Some LPAs may set higher BNG targets, so checking local policies is essential.

BNG Timeline & Key Deadlines

📅 January 2024 – BNG becomes mandatory for most major developments.

📅 April 2024 – BNG applies to smaller sites.

📅 2025 – BNG to be extended to Nationally Significant Infrastructure Projects (NSIPs).

How Artio Green Can Help

At Artio Green, we specialise in BNG assessments, ecological surveys, and Biodiversity Gain Plans. We work with planning consultants, developers, and local authorities to ensure compliance with BNG regulations.

Our services include:

🔹 BNG Calculations & Metric Assessments

🔹 Preliminary Ecological Appraisals (PEA)

🔹 Biodiversity Gain Plan Preparation

🔹 Habitat Enhancement Strategies

📞 Contact us today to discuss how we can help your project meet BNG requirements.

Biodiversity Net Gain is no longer optional – it’s a legal requirement. Developers and planners must integrate BNG into project design to secure planning permission and support environmental sustainability. By working with experienced ecologists, you can ensure a smooth application process and contribute to nature recovery.