New fields

Total count, total area (m²), and average height (m) of all outbuildings:

• premium.property.attributes.outdoor.outbuildings_summary

Area (m²), mean height (m), volume (m³), and geometry in WKT format for each outbuilding:

• premium.property.attributes.outdoor.outbuildings_details

Estimated floor level of the property:

• premium.property.attributes.status.estimated_floor_level

Maximum possible floor area, when excluding features such as stairs and interior walls:

• property.attributes.indoor.potential_floor_area

Average property value in the postcode for the property type:

• property.value.sale.average_proximal_property_value

Added support to search by postcode.

See documentation here https://docs.chimnie.org/#postcode-search

Outbuilding rebuild costs:

• premium.property.value.rebuild.outbuildings_rebuild_cost_estimate

New fields

Type of join for listed buildings, describing how the listed building data was matched against the property:

• property.attributes.status.listed_building.listed_buildings.join_type

New fields

Estimated rebuild cost for different kind of finishes.

• premium.property.value.rebuild.basic_finish_rebuild_cost_estimate
• premium.property.value.rebuild.modern_finish_rebuild_cost_estimate
• premium.property.value.rebuild.luxury_finish_rebuild_cost_estimate

Breakdowns on material and labour cost for modern finish rebuilds.

• premium.property.value.rebuild.modern_finish_material_cost_estimate
• premium.property.value.rebuild.modern_finish_labour_cost_estimate

Please note that the premium.property.value.rebuild.estimated_rebuild_cost is now deprecated and these new fields should be used instead, although the former field will be kept indefinitely for backwards compatibility.

Commercial Property Data API released.

The force_residential field is now deprecated, please use the new commercial data endpoints to request data for commercial and dual use properties.

New fields

Flag identifying a farm (True/NULL).

• property.outdoor.farmland

Whether the property is a freehold or leasehold.

• property.ownership.lease_type

The estimated banded range (e.g. 0% - 10%) of the total glazed area of the Property that is multiple glazed.

• property.attributes.status.multi_glaze_proportion

Ranged estimate of the total glazed area of the habitable area.

• property.attributes.status.glazed_area

Type of glazing (single, double, triple, etc.).

• property.attributes.status.glazed_type

Extension count.

• property.indoor.extension_count

The potential Environmental Impact Rating.

• property.bills.energy.environment_impact_potential

The type of fuel used to power the central heating e.g. Gas, Electricity.

• property.bills.energy.main_fuel

The Environmental Impact Rating.

• property.bills.energy.environment_impact_current

Suggested improvements by EPC assessors and indicative cost.

• property.bills.energy.epc_recommendations

Hot water system description.

• property.bills.energy.hotwater_description

Current CO₂ emissions in tonnes per year.

• property.bills.energy.co2_emissions_current

Potential CO₂ emissions in tonnes per year.  

• property.bills.energy.co2_emissions_potential

Main heating control description.  

• property.bills.energy.mainheat_control_description

Lighting system description.

• property.bills.energy.lighting_description

List of UPRNs that share the same grounds with the property.

• property.premium.property.attributes.status.outdoor.properties_in_grounds

New field

 Predicted property type.

• property.attributes.status.property_type_predicted

This is provided as a cheaper alternative to the declared property type from the Plus tier as it's not dependent on third party royalties.

New fields

Historical predicted market value of the property (5 years history).

• property.value.sale.historical_property_values

Predicted time window for the property to enter the market: <1y/1-2y/2-5y/5-10y/10+y

• property.value.sale.sale_propensity

New fields

Images of the property from previous listings.

• property.attributes.images.listing_images

Floorplans of the property.

• property.attributes.images.floorplan_images

Clearer predicted fields

We've improved how we expose predicted values by splitting them into three distinct categories:

• [field]_declared_only: Values officially declared in public records.
• [field]_predicted_only: Values derived purely from our prediction models. Will be null when there is a declared value available.
• [field]_declared_and_predicted: Combined values from both predicted and declared.

While the legacy fields are now deprecated, they will remain available for backwards compatibility.

For example, the bedrooms count fields are now structured as:

• New field: bedrooms_declared_only - Legacy field: bedrooms

• New field: bedrooms_declared_and_predicted - Legacy field: bedrooms_predicted

• New field: bedrooms_predicted_only -  Legacy field: N/A 

New fields

Whether the flat is converted or purpose_built.

• premium.property.attributes.status.flat_build_type

The predicted number of storeys in the block of flats.

• premium.property.attributes.status.flat_storey_count_predicted

Whether the property shares its grounds with other properties.

• premium.property.attributes.status.shared_grounds

Feature

Address autocomplete is now public.

Read more in https://docs.chimnie.com/#address-autocomplete.

New fields

The predicted council tax band for the property.

• property.bills.tax.council_tax_band_predicted

Lower and upper bounds of the property value estimate.

• property.value.sale.property_value_range

The confidence in the property value, one of high, medium, low.

• property.value.sale.property_value_confidence

Feature

Enhanced LLM phase of address matching, improving address match rates.

New fields

The risk details for a property being affected by surface water flooding, showing the individual risk for grounds and building as well as the water depth.

• property.attributes.flood.risk_details_surface_water

The price of the most recent transaction for the property.

• property.value.sale.last_transaction_price

The date of the most recent transaction for the property.

• property.value.sale.last_transaction_date

Feature

Now property.value.sale.property_value does not consume credits if requested via UPRN, as part of our Free AVM service.

More info in https://docs.chimnie.com/#free-avm.

New field

The type of risk associated with a property being affected by surface water in the event of a flood. Possible values are: No Risk, Buildings, Grounds.

• property.attributes.flood.risk_category_surface_water

Feature

Added support for json-compact and csv-compact response formats. Read more in https://docs.chimnie.com/#using-the-format-parameter.

New fields

The classification of the property. One of: Residential, Commercial, Dual Use, Parent Shell or Other.

• property.attributes.status.classification

UK region. One of East Midlands, East of England, London, North East, North West, Scotland, South East, South West, Wales, West Midlands, Yorkshire and The Humber.

• plus.property.attributes.status.region

Country. One of England, Scotland, Wales.

• plus.property.attributes.status.country

Feature

Added support for force_residential parameter, which forces the property to be residential even if the address is commercial, dual use or parent shell, so data can be returned. 

New fields

Area of the property grounds in square metres classified by surface type. Classes: built_surface, lawns, tarmac, tree_cover and other.

• premium.property.attributes.outdoor.grounds_class

Tree fall hazard index, calculated as the height of the closest tree within 10m of the property divided by the distance to the tree.

• premium.property.attributes.outdoor.tree_hazard_index

Height in metres of the closest tree within 10m of the property.

• premium.property.attributes.outdoor.closest_tree_height

Distance in metres to the closest tree within 10m of the property.

• premium.property.attributes.outdoor.closest_tree_distance

New field

Distance of the property in metres from the nearest road.

• premium.property.attributes.outdoor.distance_from_road

Breaking changes

premium.property.ownership.total_hhi_predicted is now a string with banded values, e.g "10000-20000", "20000-30000" etc.

surroundings.facilities.shops.nearest_petrol_station now has street address instead of lat/long, to be consistent with other similar fields like nearest_post_office.

property.bills.energy.heating_types has been standardised to an array with the following possible values:

• Heat Pump
• Electric Storage Heaters
• Gas Boiler
• LPG/Oil Boiler
• Underfloor Heating
• Mineral/Wood/Coal
• BioFuel
• Community Scheme
• Other Electric Heating

New fields

Air pollution.

• surroundings.environment.air.pollution_bz
• surroundings.environment.air.pollution_com8hr
• surroundings.environment.air.pollution_ozone
• surroundings.environment.air.pollution_no2
• surroundings.environment.air.pollution_nox
• surroundings.environment.air.pollution_pm10
• surroundings.environment.air.pollution_pm25
• surroundings.environment.air.pollution_so2

Flood risk from reservoirs.

• surroundings.environment.flood.reservoirs_risk_flag
• surroundings.environment.flood.reservoirs_risk_level
• surroundings.environment.flood.reservoirs_risk_details

New fields

UPRN of the containing building of the property, e.g. the block of flats where a flat is.

• plus.property.attributes.status.parent_uprn

List of sibling properties, e.g. other flats within the same block.

• plus.property.attributes.status.sibling_uprns

New field

The likelihood of the property being affected by surface water flooding in a given year, measured in % probability.

• surroundings.environment.flood.flood_risk_surface_water

New field

Support for Parent Shells. Parent Shells return a list of contained properties in plus.property.attributes.status.subproperties.

New fields

Number of reception rooms.

• property.attributes.indoor.reception_rooms

Date of declaration of number of reception rooms.

• property.attributes.indoor.reception_rooms_date

Feature

We now send notification e-mails when credits are running low and when expired.

New endpoints

Find properties by their UDPRN.

Feature

Return remaining credits in chimnie-credits-remaining response header.

New properties

We now return information on pre-builds. These are denoted by the property.attributes.status.prebuild field being true. Properties of the prebuild category are part of the Premium tier and have a cost of 3 credits.

New fields

Primary and secondary heating types.

• property.bills.energy.primary_heating_source
• property.bills.energy.secondary_heating_source

Declaration date for bedrooms and bathrooms.

• property.attributes.indoor.bedrooms_date
• property.attributes.indoor.bathrooms_date

New fields

Connected property risk data (Premium tier)

• premium.property.ownership.connected_property_risk
• premium.property.ownership.connected_property_risk_details
• premium.property.ownership.parent_property_risk_details

More granular property types (Plus tier)

• plus.property.attributes.status.property_class
• plus.property.attributes.status.property_subtype

Feature

Added support for CSV as response format.

New fields

Added roof, building and terrain fields from Lidar (Premium tier, except flat_storey_count which is Core tier)

• property.attributes.status.flat_storey_count
• premium.property.attributes.status.main_ridge_height
• premium.property.attributes.status.main_gutter_height
• premium.property.attributes.status.main_roof_slope_degrees
• premium.property.attributes.status.building_volume
• premium.property.attributes.status.roof_area_up_to_10_degrees
• premium.property.attributes.status.roof_area_up_to_5_degrees
• premium.property.attributes.status.pct_south_facing
• premium.property.attributes.status.roof_area_up_to_20_degrees
• premium.property.attributes.status.roof_area_up_to_15_degrees
• premium.property.attributes.status.roof_area
• premium.property.attributes.status.maximum_height
• premium.property.attributes.status.storey_count
• premium.property.attributes.status.property_elevation_min
• premium.property.attributes.status.property_elevation_max

Breaking change

affected_areas in all categories of surroundings.environment.land now contain an array of objects instead of an array of strings, providing more detailed data.