Open data
OKLocate Open Building Layer
Not yet published. This page is the specification for the 2026 release, published ahead of the file so the attribute list can be argued with before a CC-BY-4.0 dataset is irrevocably released.
Building height, roof area and pool detection for every US home we measure, keyed to FEMA USA Structures so it joins to that dataset without a conflation step. Creative Commons Attribution 4.0 International.
Columns
| Column | Type | Description | Status |
|---|---|---|---|
| fema_structure_id | string | FEMA USA Structures identifier. house_id is built from its OBJECTID, so the file joins to USA Structures without a conflation step. | in release 1 |
| centroid_lat | float (degrees) | Building centroid latitude, WGS 84. | in release 1 |
| centroid_lon | float (degrees) | Building centroid longitude, WGS 84. | in release 1 |
| county_fips | string | Five-digit county FIPS code. | in release 1 |
| lidar_survey_year | integer (year) | Year of the LiDAR survey the height was measured from. Null where the county has no LiDAR. | not yet |
| imagery_resolution_cm | integer (cm) | Resolution of the aerial imagery behind the detections: 30 in Illinois, 60 elsewhere. | not yet |
| building_height_ft | float (ft) | Structure height above ground, measured from classified LiDAR where the survey classifies buildings and derived from the last return of each pulse where it does not. | in release 1 |
| roof_area_sqft | float (sqft) | Plan-view roof footprint area. | in release 1 |
| pool_detected | boolean | A swimming pool was detected in aerial imagery within the parcel boundary. Omitted where the county has no parcel polygon, because the detection has no boundary to run inside. | in release 1 |
| fema_flood_zone | string | FEMA National Flood Hazard Layer zone code at the building centroid. A map overlay for analysis, not a flood determination. | not yet |
Committed, and not in release 1
Named here rather than quietly dropped, with what each one is waiting on. A column we cannot measure is omitted from the file; it is never filled with a zero or with a county figure standing in for a building.
- lidar_survey_year
- Survey year is not a served column. lidar_tile identifies the source tile; mapping tile to survey year is a lookup held in saferate-analysis.
- imagery_resolution_cm
- Derivable per county from the NAIP dataset record rather than from a served column; trivial, but it is a join at export time and not a read.
- fema_flood_zone
- No per-building flood zone exists. Requires a point-in-polygon join of every building centroid against the FEMA NFHL polygons, run at ingest in saferate-analysis. County-level SFHA share is what we hold today.
What stays in the API
Stated so the boundary is stable. A vague boundary invites the assumption that everything arrives eventually.
- Roof faces, pitch and facet counts What roofing and solar contractors pay per report for. This is the product.
- Per-face solar Which face, which direction, how big, measured plane by plane.
- LiDAR point clouds The raw survey, per house.
- Detached structures Needs a parcel boundary, and distinguishes a garage from a house.
- County search Querying every measured home on any field at once.
- Refresh cadence The open layer is an annual dated snapshot. Current data is the subscription.
Licence and citation
Released under Creative Commons Attribution 4.0 International. Cite it as:
OKLocate Open Building Layer, 2026 release, oklocate.com
Sources
What the measurements are built from, with the licence each one carries and where that licence was checked.
FEMA USA Structures
CC-BY-4.0 (attribution required)
Required notice: Contains data from FEMA USA Structures, produced by Oak Ridge National Laboratory and the FEMA Geospatial Response Office, licensed under CC BY 4.0.
Verified: The ArcGIS item behind the FeatureServer we actually query (item 0ec8512ad21e4bb987d7e848d14e7e24, owner Esri_US_Federal_Data) states: "This work is licensed under a Creative Commons by Attribution (CC BY 4.0) license." Its accessInformation credits Oak Ridge National Laboratory (ORNL) and the FEMA Geospatial Response Office. The layer itself returns an EMPTY copyrightText, so the item record is the only statement there is. Read 2026-09-04. NOTE: FEMA data is often assumed public domain as a US Government work; the thing we consume is an Esri-hosted view that declares CC BY, and what the publisher of the artefact we actually use says is what governs.
Illinois Height Modernization Program LiDAR
Public domain
USDA NAIP aerial imagery
Public domain (US Government work)
FEMA National Flood Hazard Layer
Public domain
Rules of the release
- No addresses, owner names or parcel identifiers in the release.
- Geometry and identifiers from FEMA USA Structures only. No Overture geometry and no Overture identifiers.
- A field a county cannot measure is OMITTED, never zero. Pool is omitted where the county is footprint-only.
- Annual dated snapshot. Refresh cadence stays with the API.
- GeoParquet, partitioned by state and county.