Self-build and Biodiversity Net Gain (BNG)
Small scale self and custom build development is exempt from the Biodiversity Net Gain (BNG) requirement. This exemption applies only to development that:
- consists of no more than 9 dwellings
- is carried out on a site which has an area no larger than 0.5 hectares, and
- consists exclusively of dwellings which are self-build or custom housebuilding as defined in section 1(A1) of the Self-build and Custom Housebuilding Act 2015. This definition covers development where local planning authorities are satisfied that individuals have had the primary input into the final design and layout of a house to be occupied as homes for themselves.
This size criteria will make sure only small self and custom build sites are caught by the exemption. Self and custom build sites in excess of these thresholds, which are impacting more habitat and so have more scope to deliver gains for nature will be required to deliver a net gain. This will apply whether they are a standalone development site or secured for self or custom build as part of a major development.