England Brownfield Development Opportunity Change Signals

Detect what changed since your previous run in the official England Planning Data Brownfield Land dataset.

What this Actor does

It builds a full current state for brownfield sites in England, keyed by the official Planning Data entity ID, joins the official organisation catalogue for local-authority names, and compares it with the last successful snapshot. It is designed for development, planning, land, housing, investment-research, and public-sector data teams.

Signals: NEW_BROWNFIELD_SITE, SITE_REMOVED, PLANNING_PERMISSION_CHANGED, SITE_PERMISSIONED, OWNERSHIP_STATUS_CHANGED, DWELLING_CAPACITY_INCREASED, DWELLING_CAPACITY_DECREASED, SITE_AREA_CHANGED, PERMISSION_TYPE_CHANGED, SITE_NAME_CHANGED, and END_DATE_CHANGED. Opportunity-oriented signals explain permission, ownership, and dwelling-capacity changes without claiming approval or commercial outcome. Capacity changes require valid numeric values on both sides and include absolute and percentage deltas where meaningful.

Official source, licence, and attribution

Source: the official Planning Data Brownfield Land dataset and Planning Data API, covering England. Licence: Open Government Licence v3.0. Attribution: © Crown copyright and database right; licensed under the Open Government Licence v3.0. Source: Planning Data, Ministry of Housing, Communities and Local Government. Commercial reuse, persistent storage needed for comparisons, and derived signals are permitted subject to the OGL conditions.

Planning Data collects authoritative provider data and refreshes its platform frequently; source authorities update registers on their own schedules. Weekly scheduling is a practical default, or daily when prompt detection matters.

Baseline and input

The first live run validates and stores all England sites and emits zero signals. An unchanged rerun emits zero. maxItems limits Dataset output only. Filters support signal type, local authority, postcode prefix, permission status, ownership status, and minimum capacity increase/decrease.

{"mode":"live","signalTypes":["SITE_PERMISSIONED","DWELLING_CAPACITY_INCREASED"],"minDwellingIncrease":10,"maxItems":100}

{"signalType":"DWELLING_CAPACITY_INCREASED","entityId":"1700000","siteReference":"BFR001","siteName":"Example site","localAuthority":"Example Council","previousValue":50,"currentValue":80,"absoluteDelta":30,"percentageDelta":60}

Use {"mode":"sample"} for ADWIC-friendly synthetic changes processed by the production diff engine without accessing or changing the live baseline.

Safety, storage, and limitations

The order is fetch, parse, normalize/join, validate, load/compare, Dataset, summary, snapshot commit. Fetch, pagination, required-field, schema/count anomaly, Dataset, or summary failures prevent snapshot advancement. Storage and compute are linear in the complete England dataset.

This Actor covers England only. It reflects published register data, which varies by authority and can be delayed, incomplete, re-keyed, or corrected. Some official records omit a reference or organisation identifier; the official entity ID is then retained as the displayed reference and the authority is labelled Not supplied. Site presence is not a guarantee of availability, investment suitability, planning approval, housing delivery, or development opportunity. Postcodes are extracted from official site-address text when present; some records have none.