BNGAI™ Platform: Advanced Planning and Habitat Management 

The BNGAI™ platform offers Biodiversity Net Gain (BNG) planning capabilities that empower users to optimize habitat management and development strategies: 

BNGAI™’s Planning Features 

  1. Habitat Modification: Users can adjust habitat types, conditions, strategic significance, and geometries within the site’s baseline.
  2. Linear and Point Feature Management: Add new linear features such as hedgerows or trees or convert existing linear features to different types.
  3. Integration of Post-Development Plans: For post-development plans that include complex geometries associated with built changes (e.g., housing estates with vegetated gardens, landscaping, and pathways), users can submit CAD designs for the proposed post-development layout directly to BNGAI™. BNGAI™ then incorporates these new developed area geometries into your habitat map.

Post-development enters the BNGAI™ process once the preliminary baseline assessment is completed, as demonstrated in the diagram below: 

The following BNGAI™ CAD import data standard has been created to enable post-development planning within the BNGAI™ platform and can be shared with your technical teams and partners. 

BNGAI™ CAD Import Data Standard 

Purpose  

This Data Standard for Post-Development CAD import defines the standard technical specifications for architectural and landscape CAD submitted in support of post-development planning and analysis on the BNGAI™ platform. Adherence to this standard ensures that the BNGAI™ platform analyses and interprets the post-development plan in a consistent, compliant manner, ensuring BNG calculations’ accuracy.  

File Formats 

Post-development plans should be submitted in one of the following vector formats: 

  • CAD files (.dwg / .dxg) 
  • GeoPackages (.gpkg) 
  • Shapefiles (.shp) 

CRS: EPSG:27700 – OSGB36 / British National Grid CR

BNGAI™ CAD Import Capabilities 

  • Imports new development features within the project footprint 
  • Optimised for habitats with fixed conditions (e.g., sealed surfaces) 
  • Applies default conditions to built features without fixed conditions. This can be updated during planning on the platform.  
  • Does not import CAD elements outside the built development footprint (e.g. new areas of woodland or scrub) 

 

General Data Requirements 

Important Notes

BNGAI™ Platform and CAD Submission Suitability 

  • The BNGAI™ platform does not assess the suitability of CAD files submitted for planning purposes. 
  • It is recommended that you consult a qualified ecologist before submitting plans for planning applications. 

Completing Plans on the Platform 

After importing CAD files, users must finalize the plan on the platform, which may involve: 

    • Updating habitat conditions and strategic significance. 
    • Modifying watercourse encroachment.
    • Adjusting multipliers.
    • Implementing advanced scenario actions such as bespoke compensation or non-default planning workflows.  

Plan Preparation 

Plans should be drawn up in accordance with DEFRA BNG guidelines and in reference to the site’s baseline plan.   

Layer Requirements 

  • Separate layers or files should be supplied for each of the following (see specific guidance for each file format type below). 
    • Trees  
    • Area Habitats 
    • Hedgerow Habitats  
    • Watercourse Habitats 
  • Combined layers should represent a single bird’s-eye view of the site. 

Habitat Labelling 

  • Use appropriate DEFRA BNG Habitat names where possible. 
  • When detailed plans for the housing are yet to be created, the Statutory BNG metric allows for housing development to be mapped with a suggested 70:30 ratio of sealed surfaces to vegetated gardens. This may be recorded as the habitat type “Suburban_Mosaic”. 
  • Habitat information is derived from CAD layer names. 
  • Text information on drawings will not be retained during import.
     

Data Exclusions 

Unnecessary data not relating to BNG habitats should not be supplied. This includes but is not limited to: 

  • Utility layouts (sewage, power, or other subsurface assets) 
  • Contour lines 
  • Dimensions on drawings 
  • Interior or urban feature details (e.g., building roof pitch) 

 

CAD Specific Guidance 

Layers and Naming 

Trees 

  • Trees are considered point features in BNG. 
  • A single uniform symbol should be used – a circle is preferable. 
  • The area calculated for trees in the metric is not based on the size of the feature in CAD and will default to small unless otherwise specified in line with the Biodiversity Metric.  

Area Habitats 

  • Area habitats (apart from trees) are represented by polygons on the platform. 
  • Please ensure the line work results in closed polygons, with all polygon parcel boundaries fully connected. 
  • Area habitats files should contain no block/cell features. 
  • Habitat parcels should not overlap with one another and there should be no gaps between adjacent parcels.  

Hedgerows and Watercourses  

  • Hedgerows and watercourses are considered linear features.  
  • These can be submitted as a single layer of labelled line features or as multiple layers.  
  • These lines should run along the centerline of the feature on the divide between polygons. In line with the Biodiversity Metric. 

 

Geopackage / Shapefile Specific Guidance 

Post-development plans can be submitted as a geopackage or a zipped folder containing shapefiles with the following component parts: 

1. Polypoint File  

  • Trees are represented by point features

2. Polygon File  

  • Area habitats are represented by polygons in the metric. 
  • Habitat parcels must not overlap with one another and should not have gaps between parcels.  

3. Polyline File  

  • Hedgerows and watercourses are considered linear features in the metric.  
  • These can be submitted as a single file of linear features or two separate files. 

4. Habitats should be labelled using the appropriate DEFRA BNG Habitat name.