What is a BNG assessment in the UK?

A Biodiversity Net Gain (BNG) assessment is a mandatory calculation for most UK planning applications since February 2024, under the Environment Act 2021. It measures the biodiversity value of a development site before and after construction using the Statutory Biodiversity Metric 4.0, and the developer must deliver at least a 10% uplift in biodiversity units. BioNetGain Pro produces a legally compliant BNG report in under 30 minutes.

How much does a biodiversity net gain report cost in the UK?

A BioNetGain Pro BNG report starts at £95 for sites under 0.1 hectares (micro sites). Pricing scales with site area: small sites (0.1–0.5 ha) from £195, minor developments (0.5–1 ha) from £295, and major developments (1+ ha) from £495. This is 70–90% cheaper than a traditional ecological consultancy, which typically charges £2,000–£8,000 and takes 5–10 working days.

Is BioNetGain Pro BNG report legally compliant?

Yes. Every BioNetGain Pro report uses the DEFRA Statutory Biodiversity Metric 4.0, produces a Biodiversity Gain Plan (BGP) in the Natural England-accepted format, and includes a 30-year Habitat Management and Monitoring Plan (HMMP) alongside Section 106 or Conservation Covenant legal mechanism drafting. Reports are accepted by all 317 UK Local Planning Authorities.

Which development sites need a BNG assessment?

Since 12 February 2024 most major developments in England require a 10% BNG uplift. Since 2 April 2024 small sites (fewer than 10 dwellings, or under 0.5 hectares) also require BNG. Nationally Significant Infrastructure Projects (NSIPs) come into scope in late 2025. Exemptions include householder applications, change-of-use without development, and de minimis sites under 25 m² of habitat impact.

How does the BNG calculator work?

The BioNetGain Pro BNG calculator uses the Statutory Biodiversity Metric 4.0 formula: biodiversity units = area (ha) × habitat distinctiveness × condition × strategic significance × spatial risk × temporal risk. We automate the baseline assessment with AI-processed satellite imagery via our partnership with Gentian True Sight, then apply the developer's planned scenario to calculate post-development units and the 10% gain target.

How long does a BNG report take?

A BioNetGain Pro report is delivered within 30 minutes of boundary submission. This compares with 5–10 working days for a traditional ecological consultancy. The speed comes from our AI-driven baseline habitat mapping and the automated Metric 4.0 calculation engine.

Do I need a PEA as well as a BNG report?

In most cases, yes. A Preliminary Ecological Appraisal (PEA) covers protected species, designated sites, and construction impacts — it is a separate statutory requirement from BNG. BioNetGain Pro handles the BNG compliance layer: metric calculation, HMMP, submission pack, trading rules, off-site options, and S106 drafts. Your ecologist handles the PEA. Together, the two documents satisfy the complete ecological requirements for your planning application.

Why do LPAs reject BNG reports?

The most common reasons LPAs reject BNG submissions are: no Habitat Management and Monitoring Plan (HMMP), no committed pathway to achieving 10% net gain (just a generic statement that options exist), missing trading rules analysis, no costed off-site compensation comparison, and no mitigation hierarchy narrative. BioNetGain Pro includes all of these as standard in every submission pack, giving the LPA confidence that the biodiversity gain condition is capable of being discharged before determination.

BioNetGain.Pro

East of England

Biodiversity Net Gain for Hertfordshire County Council

Everything developers, architects and planners need to meet the mandatory 10% BNG requirement for sites in the Hertfordshire County Council area — with a fully compliant report and HMMP delivered in under one hour.

Compliant report + HMMP

Submission packs accepted by Hertfordshire County Council and all English LPAs.

Under one hour

AI baseline mapping vs 5–10 days for a traditional consultant.

From £295

70–90% cheaper than a traditional ecological consultancy.

BNG requirements in Hertfordshire County Council

Since the Environment Act 2021, Hertfordshire County Council requires most new development to deliver a measurable biodiversity net gain of at least 10%. This is assessed using the Statutory Biodiversity Metric and must be secured for at least 30 years through a legal mechanism such as a Section 106 agreement or Conservation Covenant.

A baseline habitat assessment using the Statutory Biodiversity Metric
A Biodiversity Gain Plan (BGP) in the Natural England format
A 30-year Habitat Management & Monitoring Plan (HMMP, JP058)
Trading rules and mitigation hierarchy analysis
A secured legal mechanism (S106 or Conservation Covenant)

Do I need a Biodiversity Net Gain assessment for a development in Hertfordshire County Council?

Yes. Like all English Local Planning Authorities, Hertfordshire County Council requires most planning applications to demonstrate at least a 10% biodiversity net gain under the Environment Act 2021. Major developments have required BNG since 12 February 2024 and small sites since 2 April 2024.

How much does a BNG report cost for a East of England development?

A BioNetGain Pro submission pack (BNG Compliance Report + JP058 HMMP + DEFRA Metric export) starts at £295, scaling with site area. This is 70–90% cheaper than a traditional ecological consultancy.

Will Hertfordshire County Council accept a BioNetGain Pro report?

Yes. Every report uses the DEFRA Statutory Biodiversity Metric, produces a Biodiversity Gain Plan in the Natural England-accepted format, and includes the 30-year HMMP and trading-rules analysis that Hertfordshire County Council planning officers expect.

Ready to submit to Hertfordshire County Council?

Complete BNG submission pack from £295. Report + HMMP in under one hour.