Red Line • Terrain • BNG / Ecology • Planning Constraints
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Projects / Cloud sync — v2.19.2a
Cloud sync needs your own Supabase project, the supplied database schema and an HTTPS deployment. Keep offline/local backups: this release syncs structured project JSON, not raw LiDAR GeoTIFFs or uploaded photographs.
1. Cloud connection / setup
2. Sign in
3. Project workspace
Cloud project ID: New project (not yet saved)
Connect and sign in to enable cloud saving.
Manual save/load is intentional in this first cloud build. A project changed elsewhere is never silently overwritten: a conflict blocks saving and requires review. Changes made offline can be exported using the existing Save Project File control.
This output is an early-stage screening and feasibility aid. National datasets can be incomplete or out of date locally.
LiDAR is not a substitute for a commissioned topographical survey where contractual or setting-out accuracy is required.
BNG screening is not a replacement for the statutory biodiversity metric or competent ecological assessment.
Planning conclusions should be verified against current local planning policy, validation requirements and site-specific professional advice.
Guide
Use this tool for screening, preparation and optioneering. Verify material decisions against current source data and the appropriate competent professional.
BNG / Ecology Guide
How to use this tab for early-stage biodiversity screening
1. What is Biodiversity Net Gain?
Biodiversity Net Gain (BNG) is the planning requirement to leave biodiversity in a measurably better state than before development. Where mandatory BNG applies, the statutory target is generally at least 10% net gain, measured using the statutory biodiversity metric.
This app provides preliminary screening only. The simple unit values shown here are not the statutory biodiversity metric and should not be submitted as the formal BNG calculation.
2. First check: does mandatory BNG apply?
For planning applications made on or after 6 August 2026, developments with a red-line site area of 0.2 hectares or below are generally outside mandatory BNG, provided the proposal does not affect on-site priority habitat. Other exemptions and transitional rules may also apply.
The app therefore calculates the red-line area first and gives an applicability screening message. Treat this as a prompt to check the relevant exemption, not a legal conclusion.
3. Recommended workflow
Draw the red-line boundary on the Red Line tab.
Open this BNG / Ecology tab and press Sync from Red Line Site.
Review the red-line area and the applicability screening message.
If BNG may apply, identify and map the existing baseline habitats.
Draw each baseline habitat parcel separately, then assign its habitat description and screening attributes.
For individual trees, you can first use the Tree / Plant Checker, save an identification candidate, and send that observation directly into the BNG baseline tree record.
Draw the proposed post-development habitats in the same way.
Compare the baseline and proposed screening units and the indicative net change.
Use the result to decide whether the layout/habitat strategy needs further work and whether ecological input is required.
For formal submission, complete the current statutory metric and Biodiversity Gain Plan where required.
4. Baseline habitats — what to enter
Baseline habitat means what is physically present before development. A habitat parcel is a smaller part of the red-line site containing one habitat type. If your site has grass, a hedge and individual trees, you normally record those as separate habitat features rather than one combined parcel.
Habitat descriptionA plain-language or UKHab-style description of the habitat currently present, for example modified grassland, mixed scrub, developed land or woodland.
DistinctivenessA screening indication of the ecological value/rarity of the habitat. Higher distinctiveness generally means losses are harder to compensate.
ConditionA screening indication of habitat quality. Formal condition assessment depends on habitat-specific criteria and should be completed using the statutory metric guidance.
Strategic significanceWhether the habitat is strategically important in a relevant local nature recovery or biodiversity strategy. Do not assume a higher multiplier without evidence.
Draw separate polygons where habitat type or condition changes. Do not treat the whole red-line site as one habitat unless it genuinely is uniform.
5. Proposed habitats — what to enter
Habitat descriptionThe habitat intended after development or enhancement.
Distinctiveness / conditionThe target ecological quality you realistically expect to deliver, not an aspirational best case.
DifficultyA screening allowance for how difficult the target habitat is to create or enhance successfully.
TimeA screening allowance for how long the habitat takes to reach its target condition.
Strategic significanceWhether the proposed habitat contributes to an evidenced strategic ecological priority.
6. How to read the screening result
Baseline units are the app's simplified estimate of the current habitat value. Proposed units are the simplified estimate after development/enhancement. Net change compares the two.
A result above 10% does not mean the scheme is automatically compliant. The statutory metric also applies habitat-specific rules, trading rules, risk multipliers and special treatment for some habitats.
Use this tab for optioneering: compare layouts, retain higher-value habitat, increase habitat creation, or identify whether off-site units may need investigation.
7. When should an ecologist be involved?
Where BNG applies and the statutory metric is required.
Where habitats are difficult to identify or condition is uncertain.
Where priority, irreplaceable or protected habitat/species may be present.
Where the scheme is close to the 10% target or relies on complex habitat creation/enhancement.
Where the LPA asks for ecological survey, assessment or metric evidence.
Except for qualifying small developments using the Small Sites Metric, government guidance recommends that the metric is completed by a competent person such as an ecologist.
8. What this tab is good for
Early site appraisal before detailed ecological work.
Comparing development layouts.
Identifying habitat retention opportunities.
Highlighting whether ecology could materially affect site feasibility.
Preparing information for discussion with an ecologist/planner.
9. What this tab is not
It is not a Phase 1/UKHab ecological survey.
It is not the statutory biodiversity metric.
It is not evidence that protected species are absent.
It does not replace the Biodiversity Gain Plan where one is required.
It does not determine whether a planning application will be acceptable.
Guidance basis: current England BNG rules and statutory metric guidance. Always check the latest GOV.UK guidance and local planning requirements before formal submission.
Identification Results
Treat the result as an AI-assisted identification candidate. Check key features and obtain arboricultural/ecological confirmation where the species affects planning, ecology or safety decisions.
Upload photos and run identification.
Saved Tree / Plant Observations
No observations saved.
Desktop Feasibility Study
Executive Summary
Site Details
Feasibility Register
Key Actions / Recommended Surveys
Evidence / Source Summary
Assumptions and Limitations
This report is an early-stage desktop feasibility appraisal generated from the information and datasets available within the project.
It is not a substitute for formal planning advice, detailed design, commissioned topographical survey, statutory biodiversity metric,
detailed Agricultural Land Classification survey, utility searches, intrusive ground investigation, legal/title review, DNO connection offer,
or any other competent professional assessment where required. National datasets can be incomplete, historic or unsuitable for detailed design.
Findings marked Unknown or Review should be treated as evidence gaps or follow-up actions rather than as clear constraints.