Biodiversity Net Gain: Government exempts sites under 0.2ha

The housing minister Matthew Pennycook has announced a small sites exemption to Biodiversity Net Gain (BNG) despite opposition from industry leaders and professional bodies. The government has been accused of breaking its promise to protect nature. The BNG policy aims to protect and enhance habitats by stipulating that sites must have 10% more biodiversity after development.

 

Under the new rules, developments under 0.2ha are exempt – this is lower than the 1ha or 0.5ha announcement that had been anticipated, but still significant, representing 77% of all planning applications in England.

 

According to the Wildlife Trust, this would a combined area the size of Windsor Forest has been taken out of BNG. 

 

An influential group of developers and leaders from across the built environment were urging government to preserve BNG targets for most smaller sites, proposing an exemption only for micro developments under 0.1ha.

 

There are fears that undermining BNG will dent the confidence of private investors in the so-called nature markets, which have invested hundreds of millions into nature projects since the policy came into force in February 2024. 

 

The letter, coordinated by the Green Construction Board and UK Green Building Council, is signed by figures from around 120 organisations, including Wates Group, Triodos Bank, Bioregional, Atkins Realis and dozens of consultants and leading academics. 

The letter reads: "We have heard that the Government is considering removing Biodiversity Net Gain (BNG) requirements for small sites and introducing wider exemptions, that is, all sites under 1 ha or 0.5 ha will be exempt. Such changes risk severe negative implications for private investment in nature, the burgeoning nature markets, businesses striving and succeeding in the creation of sustainable, healthy and resilient places and most of all the people that live in these places."

"A 0.1 ha threshold offers a reasonable and proportionate way forwards, exempting only the 50,000+ of the smallest developments each year, while also continuing to support the integrity and function of the policy. Blanket exemptions risk disproportionate harm, lost investment, and a weakening of the UK’s international leadership in nature markets."

Dr Martina Girvan, Chair of the Green Construction Board’s Biodiversity and Environmental Net Gain Group, said: “This letter demonstrates the strength of business and expert support for Biodiversity Net Gain and for nature-positive development. Small sites are often where the loss of green space is felt most acutely, particularly in urban areas. Even modest areas of green infrastructure can deliver significant social and environmental benefits, from cooling and flood mitigation to improved health and wellbeing. Removing BNG from these sites risks embedding poorer outcomes for communities and missed opportunities to enhance the quality of places where people; risking a negative long-term legacy that neither residents or businesses want.”

 

David Pinder, Chair of the Green Construction Board, added: “The industry is clear that Biodiversity Net Gain and nature protections are not anti-growth. Proportionate and practical solutions exist. A 0.1-hectare exemption would reduce complexity for the smallest schemes without undermining nature recovery, investor confidence or the businesses that have committed to doing the right thing. A blanket exemption would be a backwards step for nature, markets and long-term value.”

The Wildlife Trust describes the move as a "Nightmare before Christmas" and the "worst environmental regression in decades."

"Following the passage of the damaging Planning & Infrastructure Bill, the Government looks set... to abandon its election commitment to ensure ‘development promotes nature recovery’ by gutting Biodiversity Net Gain, the scheme which requires homes for wildlife to be delivered alongside homes for people."

The June 2024 Labour Party manifesto read: “We will implement solutions to unlock the building of homes affected by nutrient neutrality without weakening environmental protections.”