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

1. How to get the cadastre data?

You can download the cadastral files directly online on the links available on the site of cadastre data gouv. In fact, the French cadastral map has been downloadable in open data since September 2017.

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 / 32 864 communes are concerned by 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.

1.1 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 
• Feuilles (sheets) 
• Parcelles (parcels) 
• Sections

Download

You can upload this data from : https://cadastre.data.gouv.fr/data/etalab-cadastre/latest/geojson/ (link updated on 11/2017)

You can select to download the 5 layers for : Communes (municipality) /or Departements (an entire department)

The files are compressed in Gzip format. Use a tool like 7zip to decompress them. You will get files with a .json extension.

The JSON format is recognized by QGIS as well as other GIS softwares. You just have to add a vector layer and select the JSON files to open.

1.2 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 

Download 

You can download this version from: https://cadastre.data.gouv.fr/data/dgfip-pci-vecteur/latest/edigeo/ 

You can select to download the zip file for : Departements (an entire department)

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.

1.3 Vector PCI - .DXF 

For CAD users, the DXF version of the PCI vector (Plan Cadastral Informatisé) it is available per : 

• Département
• Feuilles (sheets)

Download

You can download this version from: 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. You will get files with a .DXF extension.

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

2. How to upload files into the Alteia Platform?

Once you download the date in the format of your choice, now you can uploaded into the Alteia Platform.

2.1 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)

2.2 Upload the converted files

Click on upload a file on the Platform and choose whether to attach it to a New Survey, or to All surveys of this site (Cadastre).

Then, enter the Dataset properties required and Upload your files.