1. Description

In this article, we are going to review how to get your cadastre data into the Alteia Platform and its type of file. 

2. How to get the cadastre data?

The French cadastral map has been downloadable in open data since September 2017. 

Cadastral files could be downloaded directly online from this link. 

The cadastral plan is the division of the French territory into surface units allowing the calculation of certain taxes. Each "commune" is subdivided into sections, which are in turn subdivided into sheets. A cadastral sheet includes parcels, which can support buildings.

Multiple vector versions (extensions) are available and more than 30 000 communes are concerned with the vector version :

• JSON
•  THF
•  DXF

After downloading the open-source data, you will be able to integrate and manage your layers directly on the Alteia Platform.

2.1 JSON Data

A light version of the cadastre (produced by Etalab) is available in compressed JSON format. It contains only the data from the following layers :

• Bâtiments (buildings)
• Communes (municipalities)
• Feuilles (sheets) 
• Parcelles (parcels) 
• Sections

2.2 Download French Cadastre

Use this link to upload this data: https://cadastre.data.gouv.fr/data/etalab-cadastre/latest/geojson/

5 layers are selectable and downloadable for: Communes (municipality) /or Départements (an entire department)

The files are compressed in Gzip format. Use a tool like 7zip to decompress them. Files decompressed are in JSON format.

The JSON format is recognized by QGIS as well as other GIS software. Add a vector layer and select the JSON files to open.

2.3 Vector PCI - EDIGEO - THF

The PCI vector version (Plan Cadastral Informatisé) in EDIGEO format per department or per sheet is also available. These are the classic and complete files in EDIGEO format compressed in tar.bz.

The advantage of this type of file is that it is more complete compared to the JSON data. 

2.4 Download "Plan Cadastral Informatisé" (PCI) vector

For this version use this link for download:  https://cadastre.data.gouv.fr/data/dgfip-pci-vecteur/latest/edigeo/ 

Departments (an entire department) are downloadable in zip file.

The files are compressed in tar.bz. Use a tool like 7zip to decompress them. You will get files with a THF extension.

The THF format is recognized by QGIS and other GIS software. When using QGIS, for example, we can select the vector layers to add.

2.5 Vector PCI - DXF 

For CAD users, the DXF version of the PCI is available per : 

• Département (department)
• Feuilles (sheets)

2.6 Download PCI in DXF

For this version use this link for download: https://cadastre.data.gouv.fr/data/dgfip-pci-vecteur/latest/dxf/ 

The files are compressed in tar.bz. Use a tool like 7zip to decompress them. Files decompressed are in DXF format.

The DXF format is recognized by AutoCad / QGIS or others. On AutoCAD, for example, select the vector layers to add.

3. How to upload files into the Alteia Platform?

Once the data are downloaded in the format of your choice, upload them into the Alteia Platform.

3.1 Convert your files

Please privilege the integration on the platform of the data in geojson / projection 4326 

To do this, please convert the different input data, for example : (JSON to --> GeoJSON).

3.2 Upload the converted files

See Manual File Upload.