As part of plans to reverse rapid decline in England’s biodiversity levels, the forthcoming Environment Bill will require all new house building sites to demonstrate biodiversity net gain.

Discussed in the Government’s Planning White Paper, biodiversity net gain also intends to make towns and cities more liveable through enabling better green spaces and tree cover.

The Environment Bill will set out a specific methodology for calculating biodiversity. House builders must then prove that the value for biodiversity pre build, is exceeded upon completion by at least 10%.

Many house builders already install nest boxes and adapt fences for hedgehogs, but the regulations may require builders to go further.

Richard Cowen, Chair of CPRE Durham – the countryside charity – says there will be a need for localised solutions. “We believe it will be necessary to consider the type of habitat that is to be lost or detrimentally affected by the development, for example farmland or hedges.

“We know from the last State of Nature Report, published in 2019, that there has been significant loss of wildlife such as birds,” says Cowen.

“Hedges can be home to numerous species of insects that are valuable in themselves but also provide food for many other species.” Cowen noted that biodiversity net gain should make provision for flora as well as fauna.

“Wildflower meadows are also in serious decline and making provision for these should count towards biodiversity gain. If these are successful, they in turn are likely to attract insects which then can attract predators that may be compatible with human habitation.”

While often the preserve of house builders developing medium or large sites, Cowen notes that sustainable drainage schemes are a valuable means of attracting wildlife. Small steps that builders can take to support biodiversity on new developments include using swift bricks, as a few of these can provide nesting opportunities for swifts. Green walls can provide space for plants to grow which can then be home to many insects. Installing a tree or hedge, instead of a fence, can also go a long way to helping plants and animals.

The Bill also mentions accepting off-site provision from builders, and this could be in the form of a one-off payment or preserving an area elsewhere. There is reference in the Bill to how developments on ‘irreplaceable habitats’ will be managed. CPRE anticipates these will include, but not be limited to, ancient woodland.

Biodiversity net gain will form part of the planning process. The FMB will work with CPRE, the countryside charity, going forward to understand how planning applications can be compliant with new laws and to share best practice among Master Builders.

This article was original published in the February / March 2021 edition of the Master Builder magazine. Members can login to view a copy, non-members can access the latest edition via email.