If your site area is below 0.2ha (2,000m2) then you may claim an exemption from BNG. The site area is the same as your red line area - and needs to be the same as all your other applications. This is the area that is going to be developed. In many cases, for example, it will be the area owned by the applicant. It should typically include a point of access to a public highway, all areas that will be impacted by the works (including temporary impacts).
Steps to claiming
Step 1: Check the red-line area
Use the same red-line boundary shown on your planning application location plan.
The whole area inside the red line counts—not just the footprint of the new building or the part where construction will take place.
To use this exemption, the site must measure:
2,000 square metres or less.
Do not remove access, parking, landscaping, drainage or other land that forms part of the development simply to bring the site below 2,000 square metres. This will lead to an invalidation risk.
Step 2: Check for priority habitat
The exemption cannot be used where the development will affect priority habitat located within the development site.
If there are priority habitats on your site, the exemption may still be available, but you should provide clear evidence showing where the habitat is and why it will be unaffected.
If the development will affect priority habitat within the red line the 0.2 hectare exemption cannot be used. You will normally need to follow the Biodiversity Net Gain process or check whether another route applies.
Why do we check priority habitats within 500 metres?
The 500-metre check is a precautionary evidence check. Priority habitats often have irregular and dynamic boundaries. The main habitat area may appear to sit outside your development site, while a narrow strip, small corner or “finger” of the habitat extends towards—or into—the red-line boundary. This is the process recommended by the Government for determining the appropriate BNG regime applicants should use.
In simple terms, priority habitat can appear to creep onto the edge of a site, even where most of it is clearly located elsewhere.
Checking the wider 500-metre area allows us to:
identify the priority habitats nearest to your site;
check whether any part of them crosses the red line;
avoid overlooking a small or narrow area of habitat;
identify possible mapping or boundary issues; and
provide clearer evidence with your planning application.
What evidence should you provide?
Your application should normally include:
a red-line plan matching the planning application;
confirmation that the site measures no more than 2,000 square metres;
a map showing relevant priority habitats on or near the site;
confirmation of whether any priority habitat enters the red line; and
a short explanation of whether the development will affect it.
You must also select the correct exemption on the Planning Portal and complete the relevant follow-up questions.