Mapper since: May 05, 2012

About Me

This user is an import-only alias for User:iandees to import building footprints from the City of Chicago open data website.

Import Process

After downloading and splitting the Chicago building footprints shapefile, I converted the shapefiles into OSM format and am now importing this data set manually, a few square kilometers at a time:

  1. Download building footprint data from the open government data portal.
  2. Split shapefile into smaller pieces roughly half a mile square using a custom tool written to use ogr2ogr.
  3. Use ogr2osm to convert the shapefiles chunks to OSM. The translation is posted here.
  4. Open the resulting OSM files one at a time in JOSM
  5. Download the existing OSM data as a new layer and look for existing buildings. For each existing building:
    • If there is any user-generated information beyond "building=*", copy the tags from the new data to the existing data (usually this just adds address info)
    • otherwise delete the existing building to make way for the new data (since the new data is almost always better)
  6. Upload changes to existing data.
  7. Upload new data. Apply source=* tag to changeset.