Question 1

What is a BNG assessment in the UK?

Accepted Answer

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.

Question 2

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

Accepted Answer

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.

Question 3

Is BioNetGain Pro BNG report legally compliant?

Accepted Answer

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.

Question 4

Which development sites need a BNG assessment?

Accepted Answer

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.

Question 5

How does the BNG calculator work?

Accepted Answer

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.

Question 6

How long does a BNG report take?

Accepted Answer

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.

Question 7

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

Accepted Answer

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.

Question 8

Why do LPAs reject BNG reports?

Accepted Answer

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.

BNG Insights & Guidance

What Is Biodiversity Net Gain? A Complete Guide for Developers

HMMP Explained: Your 30-Year Habitat Management and Monitoring Plan

BNG Costs in 2026: How Much Does a Biodiversity Net Gain Report Cost?

Need a BNG Compliance Report?