# Primary heating fuel type

Primary fuel powering the building's heating system (e.g., natural gas, electric, oil, propane).

- API name: `primary_heating_fuel_type`
- Category: Property
- Type · unit: Text
- Addresses with a value: 18.9M (15.8%)
- Latest collection: Oct 1, 2026, refreshed monthly
- How values combine: Uses the first available of up to 2 source fields, in priority order.
- Derivations:
  - Observed — the attribute is directly observed.

## Links

- [Catalog page](/catalog/v2/primary_heating_fuel_type)
- [Published statistics (JSON)](https://static.faraday.ai/figv2/primary_heating_fuel_type.json)
- [API reference](/docs/reference/getattribute)