Description
A practical guide to geographic information systems and spatial datasets relevant to architectural site analysis, urban design, and heritage documentation.
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## Open Geospatial Data Sources
**OpenStreetMap (OSM)**
- Coverage: Global; building footprints, roads, land use, POIs, natural features
- Access: openstreetmap.org; Overpass API for queries; Geofabrik for bulk downloads
- Formats: PBF, OSM XML, Shapefile via export
- Strengths: Community-maintained; good coverage in urban areas globally; Humanitarian OpenStreetMap Team (HOT) provides rapid mapping of disaster-affected and under-mapped areas
- Limitation: Rural coverage in developing countries can be sparse; quality varies
- License: ODbL (Open Database License)
**Copernicus / Sentinel Data**
- Provider: European Space Agency / European Commission
- Coverage: Global satellite imagery
- Key satellites:
- Sentinel-2: 10m optical imagery, 5-day revisit — land use, vegetation, urban change detection
- Sentinel-1: Radar imagery — works through clouds; useful for ground deformation monitoring
- Sentinel-5P: Atmospheric data — air quality, NO₂, ozone
- Access: Copernicus Open Access Hub; Google Earth Engine; Microsoft Planetary Computer
- License: Free, open, no restrictions
**Natural Earth**
- Coverage: Global vector and raster data at 1:10m, 1:50m, 1:110m scales
- Use: Base mapping, country boundaries, physical features, populated places
- License: Public domain
**SRTM / ASTER GDEM**
- Coverage: Global elevation data
- Resolution: ~30m (SRTM), ~30m (ASTER GDEM)
- Use: Terrain analysis, slope mapping, viewshed analysis, watershed delineation
- License: Free
**National Open Data Portals**
- Examples: data.gov (US), data.gov.uk (UK), data.gouv.fr (France), govdata.de (Germany)
- Content varies: census data, transport, environment, property, planning applications
- Use: Site context analysis, demographic studies, transport planning
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## GIS Methods for Architecture
### Site Analysis
- **Viewshed analysis**: What is visible from a point? Identifies views to protect and views to screen
- **Solar exposure mapping**: GIS-based solar radiation analysis at urban scale — complements building-scale Ladybug analysis
- **Slope and aspect**: Terrain orientation and gradient — critical for building placement and drainage
- **Buffer analysis**: Distance-based proximity to amenities, infrastructure, environmental hazards
- **Isochrone mapping**: Walking, cycling, transit accessibility from a site — essential for transport planning and sustainability assessments
### Urban Analytics
- **Land use classification**: Mapping building functions, density, and mixed-use patterns from cadastral data or satellite imagery
- **Space syntax at urban scale**: Street network analysis predicting pedestrian movement, commercial vitality, and spatial segregation
- **Building age mapping**: Combining GIS and historical records to map construction dates across urban areas — essential for heritage zone identification
- **Environmental justice analysis**: Overlaying pollution exposure, green space access, income levels, and demographic data to identify spatial inequity
### Heritage Documentation
- **Site recording**: Georeferencing archaeological finds, architectural features, and condition assessments
- **Change detection**: Comparing satellite or aerial imagery over time to identify heritage site degradation, encroachment, or destruction
- **3D GIS**: Integrating point cloud data with geographic databases for heritage sites in landscape context
- **Risk mapping**: Combining geological, climatic, and anthropogenic risk data with heritage site locations
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## Integration with Architectural Workflows
### GIS → Rhino/Grasshopper
- **Elk** plugin: Imports OSM data (buildings, roads, terrain) into Grasshopper
- **Heron** plugin: Imports GIS data (Shapefiles, GeoTIFF) into Grasshopper
- **Urbano** plugin: Urban analysis tools within Grasshopper (walkability, accessibility)
### GIS → BIM
- **Revit GIS integration**: Limited native capabilities; IFC Georeferencing extension
- **Esri ArcGIS GeoBIM**: Connects ArcGIS with Revit models for urban-scale context
- **FME** (Safe Software): Data transformation between GIS and BIM formats
### GIS → Web Visualization
- **Mapbox GL JS**: Custom web maps with architectural data overlays
- **Kepler.gl**: Large-scale geospatial data visualization (Uber)
- **Cesium / 3D Tiles**: 3D geospatial visualization at city scale
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## Learning Resources
- **"GIS for Architects"** by Mustapha Sadeghipour Roudsari (Ladybug Tools creator) — focuses on GIS integration with parametric design
- **QGIS documentation** (docs.qgis.org) — comprehensive free reference
- **Spatial Analysis Online** — free web textbook on spatial analysis methods