Good Practice of LPAs and applicants working together on BNG

Urban&Civic deliver strategic residential-led developments of 3,000 to 10,000 homes within approximately 100 miles of London. The company acquires outline planning permission on previous low-grade agricultural or brownfield sites and delivers the infrastructure such as roads, drainage, community buildings including schools and GI. Urban&Civic also oversees the phased build out of homes by housebuilder partners over periods of 20 years or more. 

Their Sustainability Framework guides their approach in bringing forward sustainable development. The Framework is structured around five capitals:  Physical, Social, Economic, and Natural and Human which includes a BNG target of 25% across its portfolio, adopted prior to mandatory requirements. 

Urban&Civic operate a structured process that embeds BNG at every stage of a scheme’s evolution. This approach allows principles to be agreed in stages, avoiding surprises at the reserved matters stage, easing the LPA’s decision-making process and de-risking housing parcels.  

The large-scale developer chooses to retain responsibility for delivering strategic GI rather than delegating this to individual housebuilders. The BNG score is calculated on strategic GI and excludes housebuilder parcels. This maintains quality across the whole development, simplifies the planning relationship for housebuilders, and makes the development more attractive to both builder partners and future residents. 

Urban&Civic also front-load infrastructure delivery. Community facilities and green spaces are typically put in place early, so that new residents live in a maturing neighbourhood rather than a construction site. From a BNG perspective, habitats established early have more time to develop and contribute more strongly to the overall score. 

Houlton is a sustainable urban extension on the edge of Rugby, providing approximately 6,000 homes on the site of the former Post Office Rugby Radio Transmitter. Outline planning was granted in 2014, with delivery starting in 2016. By March 2026, approximately 25% of homes had been delivered, along with a secondary school and a primary school. BNG is delivered entirely on-site; no off-site mechanisms or habitat banks are required. 

The site had a low ecological baseline of mostly low-grade agricultural land used for grazing beneath transmitter masts. However, a population of Great Crested Newts (a European Protected Species) was identified, and part of the site (Normandy Hill) is a nature reserve excluded from development. The newt mitigation strategy became a central driver of the masterplan and so green corridors were designed throughout the site to allow movement between habitat areas, including newt tunnels beneath roads. These corridors shaped the urban form of Houlton and are now a defining feature of the development. 

Warwickshire County Council was one of the first authorities in England to pilot a BNG metric. Urban&Civic engaged voluntarily with the LPA, measuring Houlton and other sites against the Warwickshire methodology before BNG became mandatory. When the DEFRA 3.1 metric was published, scores were recalculated, and the portfolio average rose from approximately 9% to 23%. This evidence base led Urban&Civic to set their 25% internal target, which they have since consistently exceeded. 

Challenges 

At Houlton, securing Natural England licences to carry out development works in areas inhabited by Great Crested Newts required sustained engagement with the LPA and Environment Agency. This pre-BNG challenge effectively set Urban&Civic on a nature-positive trajectory, as demonstrating robust ecological mitigation became a prerequisite for unlocking planning permission on large, constrained sites. 

BNG knowledge and ecological expertise varies across local authorities. Where specialist ecologists are not embedded in a planning team, developers must invest more in providing ecological expertise and communicating the approach to the environment to all stakeholders including officers, local councillors and the wider community to demonstrate that development can be nature positive.  

Each new key phase requires Urban&Civic to re-engage with the LPA, update BNG assessments, and demonstrate that delivery is keeping pace with current legislation and policy. This is resource-intensive but also an opportunity to demonstrate ongoing commitment to improving standards.  

Early Pre-Application engagement: Urban&Civic invest in pre-application discussions that run throughout the development lifecycle, from initial outline planning through to phased delivery. These are not one-off events but a series of meetings and presentations covering the full range of planning considerations, of which BNG is one integrated element. Theaim is to ensure that issues are worked through iteratively so that the reserved matters applications deliver the proposals already agreed in principle at outline. 

Explaining BNG phasing: In large multi-phase schemes, BNG cannot be assessed parcel-by-parcel as individual parcels will not achieve BNG targets in isolation. Urban&Civic’s pre-application engagement includes clear explanation of how BNG is structured across the whole development, ensuring officers understand the mechanism before the formal application is submitted. This informs how BNG obligations are framed in subsequent Section 106 agreements. 

The key lessons from Urban&Civic in working with LPAs to implement BNG are 

For applicants: 

• Embed BNG in the scheme design from the start: Measure the baseline early and use the BNG score from the outset for pre-application discussions. It is far harder to achieve good outcomes when retrofitting this into a design conceived around other priorities. 
• Invest time in educating nonspecialist LPA, councillors and community stakeholders: sufficient understanding is needed to lead meaningful discussions.  
• Tell the story behind the metric: Explain habitat types, baseline scores and specific interventions, particularly where the perception of the ecological value of undeveloped land does not reflect the reality. 
• Start with a conservative BNG estimate and aim to increase this as detailed design progresses: this builds credibility and reduces commitment risk. 
• Front-load the delivery of GI where possible: Establishing habitats early will mean they mature faster and score better. 
• Explore off-site and habitat bank options early as a contingency, especially in areas where LPAs operate their own habitat banks. 

For local planning authorities: 

• Engage actively in pre-application BNG conversations: early applicant engagement is an opportunity to shape ecological outcomes before positions are fixed. 
• Understand how BNG operates in phased, large-scale schemes: The parcel-by-parcel model does not apply, and Section 106 obligations need to reflect the strategic delivery mechanism. 
• Build or commission ecological expertise: Even a basic working knowledge of the BNG metric significantly improves the quality of officer engagement and decision-making. 
• Recognise multiple benefits: BNG green infrastructure also delivers health, wellbeing, drainage, carbon sequestration and placemaking benefits: Approach BNG discussions as an opportunity to secure broader place quality. 

North Hertfordshire District Council is one of ten district councils within Hertfordshire, characterised as a predominantly rural district with market towns and notable heritage. The Council includes part of the Chilterns National Landscape which presents opportunities and constraints for biodiversity enhancement. Roundwood residential development in Great Ashby by Croudace Homes comprises 281 new homes on a greenfield site adjoining Stevenage in North Hertfordshire.  

Croudace Homes is a family-owned housebuilder, currently delivering 400-500 homes annually. With three regional offices in Caterham, Letchworth, and Theale. The company takes pride in its family ownership structure, which enables a long-term investment approach focused on sustainability and quality.  

The development at Roundwood demonstrates that high-quality BNG outcomes are achievable through collaborative, front-loaded processes even on constrained sites. The project's ultimate success rested on mutual respect, technical competence, and shared recognition that quality place-making with genuine biodiversity enhancement serves both commercial and public interest.  

The developer has set an internal target of 15% BNG where commercially viable, exceeding the statutory 10% requirement. This commitment reflects the developers' priorities around sustainability factors, including energy efficiency and biodiversity enhancement.   

For local developers and LPAs navigating the BNG statutory framework, the Roundwood case study offers a pragmatic blueprint: invest early, engage specialists, structure PPAs carefully, and maintain focus on the fundamental alignment between quality housing environments and biodiversity outcomes.  

North Hertfordshire Council maintains comprehensive BNG guidance on its website that provides a clear explanation of BNG requirements, links to relevant national guidance and tools, information about the Local Nature Recovery Strategy (LNRS) and its implications and contact details for pre-application enquiries.  

The Council has established a robust pre-application process that encourages developers to engage early on BNG matters. Pre-application engagement proved crucial when working on the scheme by helping to clarify requirements through early discussions, allowing the applicant to understand BNG expectations before significant design work commenced, avoiding costly revisions later.  Early engagement identified opportunities for enhanced biodiversity beyond the minimum requirements, and by addressing potential issues early, the formal application process proceeded more smoothly with fewer rounds of amendments.  

The Council’s pre-application advice on BNG starts with initial scoping where officers discuss the site context, likely constraints, and opportunities and provide clear direction on assessment requirements, methodology, and local priorities. Developers can submit draft assessments and proposals for informal review and the Council is available for questions and clarifications from the applicant before a formal application is made. Once an application is submitted, officers provide timely and constructive feedback on BNG assessments and proposals and engage in discussion to understand proposals and identify solutions rather than issuing formal requests for information. Officers focus on substantive issues rather than minor technicalities, maintaining momentum while ensuring good practice in BNG. 

Like many LPAs, North Hertfordshire faces significant resource challenges. The Council have worked to maximise its effectiveness within these constraints through efficient use of pre-app time by encouraging early engagement to help guide applications onto the right track from the start. The Council also charges for pre-application advice to recover costs to ensure that the service remains sustainable while providing good value to applicants who engage with it.  

This approach requires investment of officer time in capacity building, training and maintaining and updating website guidance, in addition to case work. This investment provides value to the LPA as fewer poor-quality applications are submitted that require extensive remedial work leading to more efficient planning processes with reduced delays and higher quality outcomes including better developer relationships. 

The scheme design at Roundwood addresses complex site constraints and maximises BNG through several integrated design strategies which are outlined below.   

Ancient Woodland buffers are provided along the western site boundary, understorey planting is provided within the 15m wide buffers to deter access while enhancing biodiversity, and comparable buffers are maintained along recently planted woodland to create consistent open space character and maximise habitat creation.  

The existing country lane is proposed to be closed to vehicles but retained as a horse and cycle route. Crucially, the former roadway area was reclaimed as enhanced hedgerow and grassland verge, contributing significantly to BNG scores.  

Two substantial drainage basins create permanent wetland habitat to prioritise biodiversity and visual amenity despite requiring additional underground storage crates to meet updated flood authority requirements. A small community orchard adjacent to the drainage pumping station provides high-quality habitat for specific biodiversity targets identified in baseline surveys.  

The development layout transitions from rigid, formal blocks in the southeast to more fluid, lower-density patterns in the northwest. This graduated approach emerged from workshop discussions about respecting both contexts while creating attractive, marketable 'shop window' frontages onto the permanent water features.  

This case study highlights several areas where LPAs can support developers in the effective delivery of BNG which benefits from:  

• Quality-Driven Commercial Model: Croudace Homes’ family ownership enables longer-term thinking about value creation through quality. Expertise in local authority planning policy fostered realistic expectations and constructive negotiation.  
• Early BNG Integration: Considering BNG from initial landowner discussions through to detailed design avoided costly late-stage redesigns. This early consideration is embedded in Croudace Homes business model, which involves long-term relationships with landowners and an extended timeframe that allows for iterative refinement of layouts and strategies to balance competing demands including BNG, open space, drainage, and commercial viability.  
• Investment in specialist ecological expertise: North Hertfordshire invested in internal ecological and urban design expertise to provide specialised input. Croudace Homes engaged Nicholas Pearson Associates to provide landscape architecture and ecology advice and engage directly with officers in technical workshops.

The success of the Roundwood residential development stems from good LPA resource management and collaborative working practices between the authority and the applicant. Recommendations for other organisations include: 

• Obtain leadership support: management commitment to collaborative working sets the tone for officer engagement with applicants. 
• Prioritise officer training: ensuring staff have confidence in technical matters through continued learning and participation in regional and national forums helps share knowledge, resolve novel issues and enables constructive dialogue.
• Promote regular communication: ensure that the Council and developer stay in touch throughout the process, with regular meetings and correspondence to resolve queries and refine proposals. 
• Encourage mutual respect: both parties should approach discussions with professional courtesy and understanding of each other’s constraints and objectives.  
• Adopt a joint problem-solving approach: rather than adopting an adversarial stance, both parties need to work together to identify solutions when challenges arise and focus on substantive outcomes rather than adhering to rigid processes.  
• Set out clear expectations: published guidance helps developers understand requirements before engagement and applying requirements consistently builds developer trust in the process. Providing technical guidance while remaining open to innovative proposals fosters a transparent working relationship.  

Northumberland County Council is a county-level local planning authority in the northeast of England. The Council has successfully collaborated with QTS Data Centres to plan for a nationally significant development campus of 10 data centres at Cambois, a 102-hectare former coal stocking yard site on the Blythe Estuary. 

The collaboration between the Council and QTS/Arcadis resulted in approval of a major employment project while delivering genuine biodiversity enhancement. While the approach has drawn the criticism of some who view the use of Rule 4 in enabling habitat loss, the case study demonstrates how regulatory frameworks can be applied pragmatically to deliver both economic and environmental benefits.  

The site for the Data Centre Campus was once one of the most significant employment sites in Northumberland, however it has been derelict for 20 years, during which time it has developed high ecological value, including significant areas of open mosaic habitat. The development proposal presented a unique challenge for the delivery of BNG at a time when mandatory BNG requirements were coming into effect  

The primary challenge included addressing the loss of open mosaic habitat, a scarce and valuable habitat type. Despite the applicant creating a slightly larger area of open mosaic habitat on-site through landscaping, the BNG metric (accounting for risks and time lag in habitat maturation) calculated a deficit of 152 biodiversity units of open mosaic habitat plus many units across a range of other habitat types. At the time, only 8-9 open mosaic habitat units were available on the market across England, making it practically impossible to purchase sufficient off-site credits. Open mosaic habitat is not straightforward to create at such a large scale, presenting a significant barrier to development approval. 

A solution emerged through close, pragmatic collaboration between multiple stakeholders including the Council's ecology team, who worked closely with the applicant to explore all viable options for delivering the required units. 

Advance Northumberland, the Council's arm's length development company, agreed to allocate a large site (approximately 270 hectares) at Potland Burn Habitat Bank for habitat creation comprising a highly complex mosaic of grassland, scrub and pond habitats, and the development company, QTS Data Centres, committed to funding both the habitat creation and 30-year management. The Council utilised Rule 4 of the BNG Guidance, which allows local planning authorities to deviate from the usual BNG trading rules in exceptional circumstances, in this case for the creation of a highly complex mosaic of habitats at a landscape scale  

This collaborative approach required all parties to be flexible and solution focused. There were moments when the public authorities had concerns about committing significant land or using untested regulatory provisions, but the shared commitment to delivering economic growth while meeting environmental obligations ensured the process kept moving forward.  

Arcadis was commissioned by QTS to provide environmental consultancy advice in support of the planning application. Ecology formed one part of Arcadis’s input alongside landscape architecture, contaminated land, hydrology, noise, and air quality. The outline planning application was submitted approximately eight months after commission, a rapid turnaround that was partly enabled by existing ecological data from the previous planning application on the site. 

BNG was identified as one of the most significant ecological constraints from the outset. The brownfield site at Cambois has been vacant since the decommissioning of Blyth Power station 2003. The site supports high value habitats, presenting a series of interconnected challenges: 

Open Mosaic Habitat (OMH): The unusual soil conditions created by decades of coal deposition had given rise to a significant extent of OMH on the previously developed land, a nationally rare habitat type. Natural England’s online mapping showed the entire site as OMH, this was mapped more accurately and reduced through detailed botanical surveys combined with ground investigation data, soil data, and analysis of the site’s industrial history. 

Financial viability: OMH scores highly in the BNG metric and unit availability varies on the habitat bank market. Offsetting the projected loss under standard like-for-like trading rules would have cost tens of millions of pounds, potentially making the entire scheme unviable. 

No precedent for Rule 4: Rule 4 permits the creation of different habitats in place of those lost, this was explored as an alternative approach but had not previously been applied. This meant that there was no established benchmark or case study to reference, and the guidance terminology such as “landscape scale” was undefined in BNG guidance. 

Absence of OMH units on the market: Even had like-for-like offsetting been pursued, OMH units were not available for purchase at the time. Potland Burn in Northumberland, was identified as a potential offset site. However, it was found to be unsuitable for the creation of OMH due to existing high-quality grassland soils. Importing the contaminated substrate needed to replicate OMH conditions would have been logistically and ecologically problematic. 

Securing the offset at scale: The project required approximately 70% of all available units at Potland Burn (c.274ha). No other single site in Northumberland was of sufficient scale to meet the ‘landscape scale’ requirement under Rule 4. Splitting units across multiple sites, or using a site outside the county, was rejected as it would have undermined the justification or incurred BNG metric penalties from the distance multiplier. 

Phasing complexity: The development was originally programmed across eight phases, each requiring its own BNG metric. Delays in planting within any phase can affect the metric calculation, adding to the complexity of implementing BNG through the Reserved Matters process.

Homes England is the government's housing and regeneration agency, operating in two main areas:  

Brookleigh is a new sustainable community of 3,500 homes in Mid-Sussex, acquired by Homes England in 2017-2018 from multiple landowners. The development illustrates how early engagement, strategic planning, and long-term partnership between the applicant and the LPA can deliver substantial environmental benefits alongside the delivery of homes and infrastructure. While Homes England’s position as a government agency provides some unique advantages, many of the collaborative practices demonstrated at Brookleigh can be adopted by private developers and LPAs elsewhere. The key is to establish BNG as a shared objective from the outset, build strong working relationships, and maintain dialogue throughout delivery.  

Brookleigh is a new sustainable community in Mid-Sussex, acquired by Homes England in 2017-2018 from multiple landowners. As master developer, Homes England secured control of the land and secured funding for delivery of infrastructure, delivers strategic infrastructure (such as main roads, major open spaces, ancient woodland buffer, and a primary school), parcels the site into serviced plots of 200-300 homes for housebuilders to delivery, supports developer partners through the Reserve Matters Application process , and co-ordinates delivery of transport, social and community infrastructure with stakeholders including Mid-Sussex District Council (MSDC) and West Sussex County Council (WSCC). This role enables a strategic, coordinated approach to BNG that would be difficult to achieve with fragmented land ownership and development.  

Homes England undertook extensive pre-application engagement with MSDC. This early collaboration provided several benefits including understanding Local Authority priorities through early discussions, shaping the masterplan to ensure biodiversity enhancement was central to the design development, aligning expectations on design quality, environmental standards, delivery mechanisms and reducing potential conflicts during the application process, and Building trust through early dialogue which built a collaborative partnership that will hopefully be maintained throughout the multi-year delivery of Brookleigh.  

Rather than treating BNG as a separate requirement, Homes England integrated biodiversity enhancement into the structure of the Brookleigh masterplan through strategic Green Infrastructure (GI) and ancient woodland buffer zones. Biodiversity areas were designed to connect and create ecological networks across the development, not just isolated pockets of habitat. The landscape led masterplan also preserved the most valuable habitats at Brookleigh including retaining ancient hedgerows which hold high biodiversity value.   

While the formal 10% BNG requirement only came into force in 2024, the Brookleigh development was designed to deliver substantial biodiversity gains from the outset as it was secured in the Section 106 which was completed in October 2019. The Section 106 required Homes England to provide a Biodiversity Baseline Assessment (a set of BNG calculations) and a Biodiversity Scheme, prior to commencement. The Scheme sets the post-development target BNG scores for every parcel of the site and the habitat enhancement, creation and management measures needed to achieve them. The Section 106 also requires progress reports at intervals relating to number of homes built i.e. prior to the occupation of each tranche of 500 dwellings. These will assess the current biodiversity score and any amendments needed to the biodiversity scheme to achieve the biodiversity objective.  

A key advantage of Homes England’s position as a government agency is the ability to invest in infrastructure upfront. This approach meant that major biodiversity enhancements could be delivered earlier in the development programme, ensuring ecological benefits accrued throughout the build-out period rather than being deferred to the end.  

The scheme has been recognised by Natural England and the Forestry Commission as demonstrating exemplary practice in integrating nature recovery with housing delivery.  

Homes England must balance ambitious environmental goals with the need to deliver homes efficiently. The master developer model and upfront infrastructure funding have helped achieve this balance by enabling a strategic approach where both objectives support each other rather than competing. Managing biodiversity delivery across multiple parcels being built out by different housebuilders requires co-ordination. The Design Guide and Reserve Matters review process help maintain standards but require ongoing effort and clear communication.  

The Brookleigh development has progressed through a period of significant change in biodiversity policy, from pre-NPPF 2021 requirements through to the formal introduction of mandatory 10% BNG in 2024. However, the scheme does not need to adapt to the new requirements as these only applied to Outline Planning Applications submitted after February 2024.