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3D BAG — TU Delft / Netherlands

What This Dataset Is

All ~10.8 million buildings in the Netherlands as 3D models from the 3D BAG, produced by the 3D Geoinformation Research Group at TU Delft and 3DGI.

The 3D BAG enriches the official BAG building registry (maintained by Kadaster) with building heights, roof types, volumes, and surface areas derived from the AHN national LiDAR point cloud.

The source BAG footprints (without heights) are available in this catalog as Buildings (Panden) from Kadaster.

Provider: 3D Geoinformation Research Group, TU Delft License: CC BY 4.0 (attribution required) Source: https://3dbag.nl/ Documentation: https://docs.3dbag.nl/en/

Files

Three files, two schemas:

LOD 1.3 Building Parts (14.1M rows)

Available as GeoParquet (3dbag-lod13.parquet, 747 MB, EPSG:7415) and PMTiles (3dbag-lod13.pmtiles, 1.2 GB, EPSG:4326). Same data, different formats. Buildings are split into parts where roof heights differ.

Whole Buildings (10.8M rows)

3dbag-pand.parquet (1.3 GB, EPSG:7415). One row per building with 62 attributes including volumes, surface areas, floor counts, and quality metrics. Join to LOD 1.3 parts on identificatie.

How to Access

DuckDB

Files are 747 MB and 1.3 GB. DuckDB streams via HTTP range requests.

Python

Schema — LOD 1.3 Building Parts

Field	Type	Meaning
`identificatie`	string	BAG building ID (16 chars). First 4 digits = municipality code. Links to Kadaster BAG.
`b3_pand_deel_id`	int64	Building-part ID within a building.
`b3_dd_id`	int64	Sub-part ID within a building part.
`height`	double	Building part height in meters (roof 70th percentile minus ground). Use as fill-extrusion-height.
`base_height`	double	Base elevation relative to ground in meters. Use as fill-extrusion-base for stepped parts.
`dak_type`	string	Roof type: `horizontal`, `slanted`, `multiple horizontal`, or `unknown`.
`bouwjaar`	int64	Construction year from BAG. 9999 = unknown.
`status`	string	Building lifecycle status (e.g. ).

Important Columns

For visualization:

height — building part height in meters (for 3D extrusion)
base_height — base elevation for stepped building parts
dak_type — roof type classification

For analysis (join from 3dbag-pand.parquet on identificatie):

b3_volume_lod13 — building volume in m³
b3_opp_grond — ground floor area in m²
b3_bouwlagen — estimated floor count
b3_opp_buitenmuur — exterior wall area in m²
b3_opp_dak_plat / b3_opp_dak_schuin — flat/sloped roof areas

BAG attributes (shared with Kadaster BAG):

identificatie — BAG building ID (the linking key)
bouwjaar — construction year
gebruiksdoel — building usage function
status — building lifecycle status

Geometry Notes

LOD 1.3 GeoParquet CRS is EPSG:7415 (Amersfoort / RD New + NAP height) — coordinates in meters. This is a compound 2D+vertical CRS.
Geometries are Polygon Z (3D polygons with Z coordinates).
PMTiles CRS is EPSG:4326 (WGS84) for web map display.
Bounding box (WGS84): [3.36, 50.75, 7.23, 53.50]
LOD 1.3 has ~14.1M building parts for ~10.8M buildings — one building may have multiple parts where roof heights step up or down.

3D Extrusion Rendering

The height and base_height fields are pre-computed for direct use with MapLibre GL / Mapbox GL fill-extrusion layers:

The base_height creates stepped rooflines — a church nave and bell tower render at different heights even though they share one identificatie.

Useful Query Patterns

Tallest buildings in the Netherlands

Buildings by roof type

Height distribution

Join LOD 1.3 parts with whole-building attributes

Largest buildings by volume

Solar potential — buildings with large flat roofs

Caveats

LOD 1.3 building parts ≠ buildings: One building may have multiple parts (rows). Don't count rows to get building count. Group by identificatie.
CRS is EPSG:7415: The GeoParquet uses Dutch national coordinates (meters), not degrees. Transform for web maps: ST_Transform(geom, 'EPSG:7415', 'EPSG:4326')
Height = relative: The height field in LOD 1.3 is relative to ground (ready for extrusion). Absolute heights (NAP datum) are in 3dbag-pand.parquet (b3_h_maaiveld, b3_h_nok).
NULL heights: Some buildings lack AHN coverage; their height values may be NULL or unreliable. Check b3_kwaliteitsindicator in the pand file.
Mixed-use encoding: gebruiksdoel is comma-separated (same as BAG). Use LIKE '%woonfunctie%' for all residential.
PMTiles zoom: At low zoom levels, features are dropped for performance. Full coverage at zoom 14-15.

Buildings (Panden) — Source BAG building footprints from Kadaster (2D only, no heights). Smaller and simpler if heights are not needed.

Hand-maintained agent guide (ported from this collection's llms.txt in August 2026). Update it alongside collection.json.

3D BAG — TU Delft / Netherlands

What This Dataset Is

All ~10.8 million buildings in the Netherlands as 3D models from the 3D BAG, produced by the 3D Geoinformation Research Group at TU Delft and 3DGI.

The 3D BAG enriches the official BAG building registry (maintained by Kadaster) with building heights, roof types, volumes, and surface areas derived from the AHN national LiDAR point cloud.

The source BAG footprints (without heights) are available in this catalog as Buildings (Panden) from Kadaster.

Provider: 3D Geoinformation Research Group, TU Delft License: CC BY 4.0 (attribution required) Source: https://3dbag.nl/ Documentation: https://docs.3dbag.nl/en/

Files

Three files, two schemas:

LOD 1.3 Building Parts (14.1M rows)

Whole Buildings (10.8M rows)

3dbag-pand.parquet (1.3 GB, EPSG:7415). One row per building with 62 attributes including volumes, surface areas, floor counts, and quality metrics. Join to LOD 1.3 parts on identificatie.

How to Access

DuckDB

Files are 747 MB and 1.3 GB. DuckDB streams via HTTP range requests.

Python

Schema — LOD 1.3 Building Parts

Field	Type	Meaning
`identificatie`	string	BAG building ID (16 chars). First 4 digits = municipality code. Links to Kadaster BAG.
`b3_pand_deel_id`	int64	Building-part ID within a building.
`b3_dd_id`	int64	Sub-part ID within a building part.
`height`	double	Building part height in meters (roof 70th percentile minus ground). Use as fill-extrusion-height.
`base_height`	double	Base elevation relative to ground in meters. Use as fill-extrusion-base for stepped parts.
`dak_type`	string	Roof type: `horizontal`, `slanted`, `multiple horizontal`, or `unknown`.
`bouwjaar`	int64	Construction year from BAG. 9999 = unknown.
`status`	string	Building lifecycle status (e.g. ).

Important Columns

For visualization:

height — building part height in meters (for 3D extrusion)
base_height — base elevation for stepped building parts
dak_type — roof type classification

For analysis (join from 3dbag-pand.parquet on identificatie):

b3_volume_lod13 — building volume in m³
b3_opp_grond — ground floor area in m²
b3_bouwlagen — estimated floor count
b3_opp_buitenmuur — exterior wall area in m²
b3_opp_dak_plat / b3_opp_dak_schuin — flat/sloped roof areas

BAG attributes (shared with Kadaster BAG):

identificatie — BAG building ID (the linking key)
bouwjaar — construction year
gebruiksdoel — building usage function
status — building lifecycle status

Geometry Notes

LOD 1.3 GeoParquet CRS is EPSG:7415 (Amersfoort / RD New + NAP height) — coordinates in meters. This is a compound 2D+vertical CRS.
Geometries are Polygon Z (3D polygons with Z coordinates).
PMTiles CRS is EPSG:4326 (WGS84) for web map display.
Bounding box (WGS84): [3.36, 50.75, 7.23, 53.50]
LOD 1.3 has ~14.1M building parts for ~10.8M buildings — one building may have multiple parts where roof heights step up or down.

3D Extrusion Rendering

The height and base_height fields are pre-computed for direct use with MapLibre GL / Mapbox GL fill-extrusion layers:

The base_height creates stepped rooflines — a church nave and bell tower render at different heights even though they share one identificatie.

Useful Query Patterns

Tallest buildings in the Netherlands

Buildings by roof type

Height distribution

Join LOD 1.3 parts with whole-building attributes

Largest buildings by volume

Solar potential — buildings with large flat roofs

Caveats

LOD 1.3 building parts ≠ buildings: One building may have multiple parts (rows). Don't count rows to get building count. Group by identificatie.
CRS is EPSG:7415: The GeoParquet uses Dutch national coordinates (meters), not degrees. Transform for web maps: ST_Transform(geom, 'EPSG:7415', 'EPSG:4326')
Height = relative: The height field in LOD 1.3 is relative to ground (ready for extrusion). Absolute heights (NAP datum) are in 3dbag-pand.parquet (b3_h_maaiveld, b3_h_nok).
NULL heights: Some buildings lack AHN coverage; their height values may be NULL or unreliable. Check b3_kwaliteitsindicator in the pand file.
Mixed-use encoding: gebruiksdoel is comma-separated (same as BAG). Use LIKE '%woonfunctie%' for all residential.
PMTiles zoom: At low zoom levels, features are dropped for performance. Full coverage at zoom 14-15.

Buildings (Panden) — Source BAG building footprints from Kadaster (2D only, no heights). Smaller and simpler if heights are not needed.

Hand-maintained agent guide (ported from this collection's llms.txt in August 2026). Update it alongside collection.json.

1INSTALL spatial; LOAD spatial;
2
3-- LOD 1.3 building parts with heights
4SELECT identificatie, height, base_height, dak_type, bouwjaar, gebruiksdoel
5FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet')
6LIMIT 5;
7
8-- Whole buildings with full 3D attributes
9SELECT identificatie, b3_volume_lod13, b3_opp_grond, b3_bouwlagen, b3_dak_type
10FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-pand.parquet')
11LIMIT 5;

1INSTALL spatial; LOAD spatial;
2
3-- LOD 1.3 building parts with heights
4SELECT identificatie, height, base_height, dak_type, bouwjaar, gebruiksdoel
5FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet')
6LIMIT 5;
7
8-- Whole buildings with full 3D attributes
9SELECT identificatie, b3_volume_lod13, b3_opp_grond, b3_bouwlagen, b3_dak_type
10FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-pand.parquet')
11LIMIT 5;

1SELECT identificatie, height, bouwjaar, gebruiksdoel, dak_type
2FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet')
3WHERE height > 50
4ORDER BY height DESC
5LIMIT 20

1SELECT identificatie, height, bouwjaar, gebruiksdoel, dak_type
2FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet')
3WHERE height > 50
4ORDER BY height DESC
5LIMIT 20

1SELECT dak_type, COUNT(*) as cnt
2FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet')
3GROUP BY dak_type
4ORDER BY cnt DESC

1SELECT dak_type, COUNT(*) as cnt
2FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet')
3GROUP BY dak_type
4ORDER BY cnt DESC

1SELECT
2    CASE
3        WHEN height < 5 THEN '0-5m'
4        WHEN height < 10 THEN '5-10m'
5        WHEN height < 20 THEN '10-20m'
6        WHEN height < 50 THEN '20-50m'
7        ELSE '50m+'
8    END AS height_range,
9    COUNT(*) AS building_parts
10FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet')
11GROUP BY 1
12ORDER BY 1

1SELECT
2    CASE
3        WHEN height < 5 THEN '0-5m'
4        WHEN height < 10 THEN '5-10m'
5        WHEN height < 20 THEN '10-20m'
6        WHEN height < 50 THEN '20-50m'
7        ELSE '50m+'
8    END AS height_range,
9    COUNT(*) AS building_parts
10FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet')
11GROUP BY 1
12ORDER BY 1

1SELECT
2    p.identificatie,
3    l.height,
4    p.b3_volume_lod13,
5    p.b3_opp_grond,
6    p.b3_bouwlagen,
7    p.b3_dak_type
8FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet') l
9JOIN read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-pand.parquet') p
10  ON l.identificatie = p.identificatie
11WHERE p.b3_volume_lod13 > 50000
12ORDER BY p.b3_volume_lod13 DESC
13LIMIT 20

1SELECT
2    p.identificatie,
3    l.height,
4    p.b3_volume_lod13,
5    p.b3_opp_grond,
6    p.b3_bouwlagen,
7    p.b3_dak_type
8FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet') l
9JOIN read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-pand.parquet') p
10  ON l.identificatie = p.identificatie
11WHERE p.b3_volume_lod13 > 50000
12ORDER BY p.b3_volume_lod13 DESC
13LIMIT 20

1SELECT identificatie, oorspronkelijkbouwjaar, b3_volume_lod13,
2       b3_opp_grond, b3_bouwlagen, b3_dak_type, status
3FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-pand.parquet')
4WHERE b3_volume_lod13 IS NOT NULL
5ORDER BY b3_volume_lod13 DESC
6LIMIT 20

1SELECT identificatie, oorspronkelijkbouwjaar, b3_volume_lod13,
2       b3_opp_grond, b3_bouwlagen, b3_dak_type, status
3FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-pand.parquet')
4WHERE b3_volume_lod13 IS NOT NULL
5ORDER BY b3_volume_lod13 DESC
6LIMIT 20

1SELECT identificatie, b3_opp_dak_plat, b3_opp_dak_schuin,
2       b3_dak_type, oorspronkelijkbouwjaar
3FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-pand.parquet')
4WHERE b3_dak_type = 'horizontal'
5  AND b3_opp_dak_plat > 500
6ORDER BY b3_opp_dak_plat DESC
7LIMIT 20

1SELECT identificatie, b3_opp_dak_plat, b3_opp_dak_schuin,
2       b3_dak_type, oorspronkelijkbouwjaar
3FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-pand.parquet')
4WHERE b3_dak_type = 'horizontal'
5  AND b3_opp_dak_plat > 500
6ORDER BY b3_opp_dak_plat DESC
7LIMIT 20

1import geopandas as gpd
2
3# LOD 1.3 building parts
4gdf = gpd.read_parquet(
5    'https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet',
6    columns=['identificatie', 'height', 'base_height', 'dak_type', 'bouwjaar', 'geom']
7)

1import geopandas as gpd
2
3# LOD 1.3 building parts
4gdf = gpd.read_parquet(
5    'https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet',
6    columns=['identificatie', 'height', 'base_height', 'dak_type', 'bouwjaar', 'geom']
7)

1map.addLayer({
2  id: 'buildings-3d',
3  type: 'fill-extrusion',
4  source: '3dbag',
5  'source-layer': 'buildings',
6  paint: {
7    'fill-extrusion-height': ['get', 'height'],
8    'fill-extrusion-base': ['get', 'base_height'],
9    'fill-extrusion-color': '#D4D4D4',
10    'fill-extrusion-opacity': 0.85
11  }
12});

1map.addLayer({
2  id: 'buildings-3d',
3  type: 'fill-extrusion',
4  source: '3dbag',
5  'source-layer': 'buildings',
6  paint: {
7    'fill-extrusion-height': ['get', 'height'],
8    'fill-extrusion-base': ['get', 'base_height'],
9    'fill-extrusion-color': '#D4D4D4',
10    'fill-extrusion-opacity': 0.85
11  }
12});

Dutch Portolan Demo

Dutch Portolan Demo

3D BAG — TU Delft / Netherlands

What This Dataset Is

Files

LOD 1.3 Building Parts (14.1M rows)

Whole Buildings (10.8M rows)

How to Access

DuckDB

Python

Schema — LOD 1.3 Building Parts

Important Columns

Geometry Notes

3D Extrusion Rendering

Useful Query Patterns

Tallest buildings in the Netherlands

Buildings by roof type

Height distribution

Join LOD 1.3 parts with whole-building attributes

Largest buildings by volume

Solar potential — buildings with large flat roofs

Caveats

Related Data in This Catalog

3D BAG — TU Delft / Netherlands

What This Dataset Is

Files

LOD 1.3 Building Parts (14.1M rows)

Whole Buildings (10.8M rows)

How to Access

DuckDB

Python

Schema — LOD 1.3 Building Parts

Important Columns

Geometry Notes

3D Extrusion Rendering

Useful Query Patterns

Tallest buildings in the Netherlands

Buildings by roof type

Height distribution

Join LOD 1.3 parts with whole-building attributes

Largest buildings by volume

Solar potential — buildings with large flat roofs

Caveats

Related Data in This Catalog