Planning and constraints
Brownfield land
Previously developed land; local authorities keep a register of brownfield sites suitable for housing, which MarketCode reads as a designation.
Also called: brownfield register, previously developed land, brownfield site.
Definition
Brownfield land, as the data uses it
Brownfield is land that has been built on before: former industrial, commercial or housing sites. Since 2017 every English planning authority publishes a brownfield land register listing sites it considers suitable for residential development, with an indicative capacity, and policy favours brownfield over green belt and greenfield.
The register is one of the designations MarketCode returns for a location and one of the filters the sourcing search accepts. Being on the register is a signal that the authority expects housing there; it is not a permission, and a site's constraints still need checking.
Tools
Tools that return it
Planning designations at a location
planning_designations()Every planning designation affecting a location, in one call: conservation
Search land or units by criteria
sourcing_search()Find land parcels or residential units matching investment criteria — the sourcing tool. Give a `location` (place or area name) or a `bbox`.
Site appraisal dossier
site_appraisal()Everything known about ONE site, assembled and judged — the site dossier.
See also
Related terms
- Green belt: Land around cities designated to prevent urban sprawl, where new building is inappropriate except in defined circumstances; one of the designations MarketCode checks live.
- Plot utilisation (built coverage): The share of a land parcel covered by building footprint; a low figure on a large parcel is the signature of an under-built site.
FAQ
Questions about brownfield land
What does Brownfield land mean?
+
Previously developed land; local authorities keep a register of brownfield sites suitable for housing, which MarketCode reads as a designation.
Which MarketCode tools return brownfield land?
+
Planning designations at a location, Search land or units by criteria, Site appraisal dossier. Each runs as an MCP tool in Claude, ChatGPT, Codex and Cursor and as a REST endpoint with an API key, at the same price.
Is previously developed land the same thing?
+
Yes. brownfield register, previously developed land, brownfield site are other names for what this entry defines; MarketCode uses "Brownfield land" in its tool descriptions and responses.
See it on a real address.
Thirty minutes, your property or area, every figure sourced.