The biodiversity gain condition in Schedule 7A explained
The biodiversity gain condition is deemed onto permissions rather than written on the decision notice. It is a pre commencement condition, and programming for it is the real problem.
The biodiversity gain condition in Schedule 7A to the Town and Country Planning Act 1990 is deemed onto planning permissions rather than written onto them, which is why so many self-builders never see it on their decision notice and then discover it the week before they intended to start. It is a pre commencement condition. Development may not begin until a biodiversity gain plan has been submitted to the local planning authority and the authority has approved it. Knowing that, and programming for it, is the whole of the practical problem.
Why the condition is deemed rather than written
Schedule 7A was inserted into the 1990 Act by the Environment Act 2021. It provides that planning permission granted for development in England is deemed to have been granted subject to the biodiversity gain condition, with exceptions set out in regulations.
Deemed means automatic. The condition applies whether or not it appears in the list of conditions on the decision notice, and an authority that forgets to mention it has not disapplied it. Some authorities do add an informative, and many do not.
The requirement took effect for major development from 12 February 2024 and for small sites from 2 April 2024, and applications made before the relevant date are not caught. So the first check on any permission is when the application was made rather than when it was granted.
The gain objective itself is a 10 per cent increase in biodiversity value over the pre development value, calculated using the statutory metric, maintained for at least 30 years.
What the gain plan has to contain
Regulations made in 2024 prescribe the content of the biodiversity gain plan and modify Schedule 7A for particular kinds of permission. In substance the plan has to set out:
- the pre development biodiversity value of the onsite habitat, and the date it was assessed
- the steps taken to minimise adverse effect on that value, which is the mitigation hierarchy applied to the scheme as approved
- the post development value of the onsite habitat
- any registered offsite biodiversity gains allocated to the development, and their provider
- any statutory biodiversity credits purchased
The plan is the developer's document and the authority's decision. It is not a survey report, though it stands or falls on the survey work behind it, and the metric file normally accompanies it. A biodiversity net gain assessment is where that narrative and the evidence list come together, and the metric and habitat condition assessment behind it are work for a competent person under the Environment Act regime rather than for a drafting tool.
Who approves it, and when
The local planning authority that granted permission approves the plan. The regulations set the period within which it must determine the submission and provide a route where it refuses or does not decide, so check the current regulations for the period and the procedure before you programme around them.
Two consequences follow for a small scheme.
The plan cannot be submitted before permission exists, because it has to describe the development as approved. And it has to be approved before any material operation on site, which means the approval sits in the critical path between consent and a start on site, alongside the discharge of any other pre commencement conditions.
Authorities are increasingly asking for the metric with the application, through the local validation list, which is sensible. It lets the officer see the gain position before deciding, and it means the plan submission afterwards is largely a formality rather than a fresh exercise.
The exemptions, and how narrow they are
The exemptions are set out in regulations and they are tighter than most applicants assume.
| Exemption | The limit that catches people |
|---|---|
| De minimis development | Under 25 m² of onsite habitat affected and under 5 m of onsite linear habitat such as hedgerow |
| Householder applications | Only the householder application type, not any small residential scheme |
| Self-build and custom housebuilding | No more than 9 dwellings, site no larger than 0.5 hectare, and wholly self or custom build |
| Biodiversity gain sites | Development on land already registered to provide offsite gains |
| Urgent Crown development | Narrow and rarely relevant to private schemes |
The de minimis threshold is where most disputes arise. A garden plot is habitat, so a new dwelling in a back garden will normally exceed 25 m² of habitat affected. A scheme entirely on existing hard standing with no hedgerow removal may fall under it, and the way to establish that is a habitat plan showing what exists rather than an assertion.
The self-build exemption has procedural requirements rather than applying by itself. Get the evidence of self-build or custom build status in order at the right time, because claiming it later is much harder.
Development permitted by a development order is outside the condition, since the condition attaches to permission granted on an application. That is why a conversion under a prior approval class does not carry the gain condition while an equivalent full application does.
Phased development and irreplaceable habitat
Where a permission is granted subject to a condition requiring development to proceed in phases, the regulations provide for an overall gain plan together with a plan for each phase, so the gain objective is tested across the whole and delivered progressively.
Irreplaceable habitat is treated separately. Where a site contains habitat on the list in the regulations, which includes ancient woodland and ancient or veteran trees, the metric does not apply in the usual way and bespoke compensation is required, agreed with the authority. Finding one of these on a site late is a scheme changing event rather than a costing adjustment.
Where the site also engages other habitats regimes, the interaction matters. A site in a nutrient neutrality catchment has a separate obligation under the habitats regulations, covered in the article on nutrient neutrality and the habitats regulations assessment, and a site with ponds may need the licensing route described in the article on great crested newt district level licensing. Meeting one of those does not satisfy the gain condition.
What happens if you start before approval
Starting work in breach of a pre commencement condition means the development is unlawful. The authority can serve a breach of condition notice or an enforcement notice, and in serious cases seek an injunction.
There is a second and less obvious risk. Where a start on site is intended to implement the permission before its time limit expires, works carried out in breach of a pre commencement condition may not count as a lawful implementation. The permission can then lapse, leaving the developer with unlawful works and no consent.
An illustrative example: a single dwelling on a corner of a paddock, permission granted in the spring, works planned to start in June. The baseline habitat survey had not been done, and the only sensible survey window for the grassland was already closing. The choice was to survey in the current season and accept precautionary assumptions, or wait until the following April. The client started on the drainage connection in the meantime, which was a material operation, and the authority wrote within a fortnight. That is an avoidable sequence, and it is a common one.
Sequencing on a small site
- Commission the baseline habitat survey before the application, in the survey season, and map habitats to the classification the metric uses.
- Run the metric on the proposed layout and adjust the layout while a change still costs little.
- Submit the metric with the application where the local validation list asks for it, and where it does not.
- On grant, prepare and submit the biodiversity gain plan, allowing for the determination period in the programme.
- Secure any offsite units and the 30 year mechanism before the plan is submitted rather than after.
- Do not carry out any material operation, including site clearance or a service connection, until the plan is approved and other pre commencement conditions are discharged.
The report index shows where the gain work sits among the other documents a small residential scheme needs, and reform news is tracked on the planning law timeline.
As at 17 September 2026 the regime described here is in force for applications made on or after the dates given above, with the detail in the 2024 regulations. Verify the current regulations and any amendments on legislation.gov.uk before relying on this summary.
This is general guidance rather than legal advice. Check the position with your local planning authority or a qualified ecologist before relying on it.
PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. For specialist technical reports, qualified professional input may be required.
Frequently asked questions
Why is the gain condition not listed on my decision notice?
Because it is deemed. Schedule 7A to the Town and Country Planning Act 1990 provides that planning permission for development in England is treated as granted subject to the biodiversity gain condition, subject to exemptions. An authority that does not mention it has not disapplied it. Some add an informative and many do not.
When did the requirement start applying?
For major development from 12 February 2024 and for small sites from 2 April 2024. Applications made before the relevant date are not caught, so the first check on any permission is the date the application was made rather than the date it was granted. Verify the position for any unusual permission type.
Does the de minimis exemption cover a garden plot?
Usually not. Garden land is habitat, so a new dwelling in a back garden will normally affect more than the 25 square metres of onsite habitat the exemption allows, and the hedgerow limit of five metres is easily exceeded. A scheme wholly on existing hard standing may qualify, evidenced by a habitat plan rather than an assertion.
Can I submit the biodiversity gain plan with my application?
No, because the plan has to describe the development as approved, so it follows the grant of permission. Many authorities now ask for the metric with the application through the local validation list, which lets the officer see the gain position before deciding and makes the later plan submission straightforward.
What happens if work starts before the plan is approved?
The development is unlawful and the authority can serve a breach of condition notice or an enforcement notice. There is a further risk that works carried out in breach of a pre commencement condition do not count as lawfully implementing the permission, so the permission can lapse, leaving unlawful works and no consent.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.