Site Context Generator

ArchiTool
Checking your session…
About Site Context Generator·Grab buildings, roads and terrain straight into CAD.

What Site Context Generator does

Search an address, choose how much of the neighbourhood you need, and get buildings with heights, roads at their real width, trees, water, land use and terrain — as a 3D context model, or a 2D plan in one of thirteen styles laid out on a sheet at scale.

Source:
Public mapping data
Output:
.3dm · DXF · PDF · SVG · OBJ · Revit
Modes:
3D model · 2D plan

How it works

Built from open mapping data. The ArchiTool site engine assembles buildings, water, green and roads for the area you choose; the 3D model and the CAD file are then made in your browser, and your own model is never uploaded. The honest caveat is upstream: the geometry is only as complete as what has been mapped at your site.

  • Buildings (with building parts and courtyards), water and green from Overture Maps, which combines OpenStreetMap with footprints from other open sources where OSM is thin.
  • Roads and trees from OpenStreetMap via Overpass, per layer, so an unticked layer is never fetched; if the site engine is unavailable, every layer comes from OpenStreetMap instead.
  • Address search resolved through Nominatim.
  • Terrain from open elevation tiles, stitched and meshed to the extraction radius.
  • Building heights from recorded height or floor counts; a building with neither takes the typical height of nearby recorded buildings, labelled as estimated, or a stated default where none are nearby.
  • Recorded roof shapes (gabled, hipped, pyramidal, single-slope, dome) built on top of the walls.
  • Rivers and lakes kept whole with their islands and set level, with the terrain lowered under them; bridges span what they cross.
  • Roads given real width from their classification and tags rather than drawn as centrelines.
  • .3dm written client-side with rhino3dm, layered so the context arrives in Rhino already organised.

How to use it

  1. Find your site. Search an address, paste "lat, lon" or pick a sample site; drag the pin or use Set centre.
  2. Size the area. Set the Area radius (up to 2 km in 3D, 4 km in 2D), or use Draw area or Use view.
  3. Mark your site. Optional: Draw site to outline your plot, or click a city border and use it as the site.
  4. Choose the layers. Buildings, Roads, Terrain, Land use, Water, Trees, Site details and borders.
  5. Add your survey. Optional: drop a DWG site survey for the ground, kerbs and plot. It stays on your computer.
  6. Generate the preview. Previews are free. Switch between 3D model and 2D plan and check estimated heights in the Legend.
  7. Pick a look. Colour the 3D model by use or height, or choose one of 13 plan presets; Customise and Save to my styles.
  8. Set the sheet. In 2D, the sheet bar under the plan sets Scale, Paper, Orientation and Title block (the title, legend, scale bar and credits beside the plan: untick it to export the drawing alone); Move plan places the plan on the sheet. The sheet is remembered for each site.
  9. Export. Download .3dm, DXF, PDF, SVG, OBJ, STL and more, or Send to Revit. The credit cost shows before you download.

Best used for

  • Getting a site model into Rhino in minutes instead of an afternoon of tracing.
  • Backdrop and context massing for shadow, wind, view and daylight studies.
  • Early massing work where the neighbours matter more than their detail.
  • Competition and feasibility work on sites you cannot visit.

Not a substitute for

  • Survey-grade context, boundary lines or anything dimensional you will build to.
  • Planning submissions without a measured survey behind them.
  • Confirming that something is not there — an empty area usually means unmapped.

Known limits

  • OpenStreetMap coverage is volunteer-made and uneven: excellent in some cities, sparse a few streets away, and occasionally years out of date.
  • Many buildings have no recorded height; those are estimated from nearby buildings or set to a default, and labelled so in the export.
  • Roof shapes appear only where they are recorded; other buildings are flat-topped, and balconies and projections are not modelled.
  • River and lake beds are not measured: the ground under water is a placeholder just below the surface.
  • Terrain is open elevation data at tile resolution, which smooths real ground and can float or bury buildings on steep sites.
  • Public Overpass mirrors are rate-limited; a sparse result can be a truncated query rather than an empty site, so re-run before believing it.

Read the full Site Context Generator guide →