How to draw a site analysis diagram
Order and ground rules for site analysis diagrams in a design report, the manual workflow, and the part sitedia does.
Overview
A design report usually opens with the site analysis. Analysis diagrams carry the facts from the site survey through to design decisions.
| Stage | Content | Example |
|---|---|---|
| Survey | Collecting facts | Surrounding buildings, protected areas, location of stops |
| Analysis | Deriving design decisions from those facts | The perimeter block has five storeys, so the new building takes up that height; the route from the U-Bahn runs along one street, so the entrance is on that street |
A common mistake is to mix the two stages. A diagram shows one fact as an image that can be read in a few seconds. The decision is drawn on top with an arrow. One fact per plate.
Core themes
| Theme | Content | Question |
|---|---|---|
| Use (existing) | Housing, retail, offices, education | How the surroundings are used |
| Planning | Land-use plan and development plans (Berlin, Cologne), actual land use (Stuttgart, Karlsruhe), listed buildings, protected areas | Which requirements and protections apply |
| Height | Distribution of tall and low buildings | Skyline and sunlight |
| Building age | When the buildings were built | Historic fabric and places of change |
| Open space | Parks, squares, water | Open spaces the site connects to |
| Access | Street hierarchy, stations, stops | How people and vehicles arrive |
Themes are added or dropped depending on the brief. Which plates belong to which theme is listed in The 28 plates.
Radius
The radius is set before the themes. It describes the area the site relates to. In sitedia it ranges from 200 m to 1.5 km (default 800 m).
| Radius | Extent | Note |
|---|---|---|
| 200–300 m | Immediate surroundings (neighbouring heights, street width, direct overshadowing) | The only scale at which individual parcels are clearly legible |
| 500 m | About 6 minutes on foot; a common unit for a station area | Used most often; several blocks and the grain of the built fabric become visible |
| 800 m | 10 minutes on foot; neighbourhood analysis | Read in groups and routes, not building by building |
| 1,000–1,500 m | The site's position in the city (main roads, large parks, links between stations) | Parcels and use colours can no longer be told apart |
The radius is chosen so that the reasons for the design decision lie inside it. If the station is 700 m away and the plate ends at 500 m, the plate does not support the argument about the station.
Frame shape
Circle
| Reason | Explanation |
|---|---|
| Matches catchment areas | «800 m around the station» and «10 minutes on foot» describe a catchment area, which a circle shows |
| Site in the centre | With the site marker in the centre, the eye returns to the same point on every plate |
| Plates in series | 6 or 12 circles of the same radius in a grid keep one scale across all plates |
Same scale. If one plate covers 600 m and the next 850 m, the two cannot be compared. One radius applies to all plates.
When a rectangle is better
| Case | Problem with the circle | Rectangle |
|---|---|---|
| Long site | Along a river or a railway the circle cuts off the ends or leaves the middle empty | Follows the proportions of the site |
| Report format | A 16:9 slide or a two-column page leaves wide margins | Fills the format |
| Area boundaries | A conservation or redevelopment area cut by the circle does not show where it ends | Takes in the whole area |
One shape per report. If the shape changes, the scale is stated again. The options are «Circle», «Square» and «Rectangle»; the default is the circle.
Colour and legend
| Principle | Content |
|---|---|
| One colour range per theme | One colour range for the theme of the plate, everything else grey |
| Legend matches the drawing | If a category is hidden or a colour is changed, the legend changes too |
| Unknown stays unknown | Buildings without a use or age stay light grey («Unknown»). An invented colour turns the whole plate into a guess |
| One accent colour | If the site marker is red, red is used for nothing else |
| North up | The plate is not rotated; shadows, sun and wind cannot be checked on a rotated plate |
Five common mistakes
| Mistake | Effect | Fix |
|---|---|---|
| Two themes on one plate | Every colour has to be looked up in the legend | Split the plates |
| Legend differs from the drawing | The plate loses credibility, and the other plates with it | Correct the legend together with the drawing |
| Colouring the unknown | The plate becomes an assumption | Leave it grey |
| No scale, no north arrow | Common when plates are placed one by one on slides | State scale and north (with a circle, the radius replaces the scale) |
| Facts without decisions | Ten plates that end with «existing situation» are a survey, not an analysis | Write one sentence with the conclusion for each plate |
Stating the limits of the data
| Approach | Content |
|---|---|
| Mark the unknown | Leave unknown buildings grey and keep «Unknown» in the legend. Areas with many unknown buildings are checked on site |
| State the date | One line with the data date in the caption (for example «Heights: 3D building model LoD2») |
| Name estimates | Building age is estimated (Berlin per block, Cologne from a model, Stuttgart and Karlsruhe from the 100 m grid of the 2022 census); missing heights are estimated from storeys |
Workflow
By hand
- Trace a map or aerial photo at one scale
- Place it in Illustrator and trace the building outlines
- Check uses on site and colour each building
- Add planning data, streets and green space as layers
- Clip with a circular mask, add legend, scale and north arrow
For another site, the geometry and data sources have to be assembled again.
Automated
The material is open data from the federal states and cities. For buildings, parcels and addresses the Germany edition uses the ALKIS property cadastre, for heights the LoD2 3D building models, for terrain the DGM1 digital terrain model, for stops the timetable data of VBB, VRS and NVBW, and for planning data the data from Geoportal Berlin and the City of Cologne. sitedia puts these data together for an address in Berlin, Cologne, Stuttgart or Karlsruhe and draws up to 28 plates following the principles above (circular frame, fixed scale, unknown in grey, legend matching the drawing). PNG downloads are free; the editable SVG is part of the Pro pass (Pricing).
Open data can miss new buildings or contain old uses. The last step is therefore a review by someone who knows the place. This is why the output is editable; see Finishing the SVG.
Order in the report
- Location: location map and aerial photo
- Planning: planning data, listed buildings and protected areas, parcels
- Surroundings: buildings, use, building age, height
- Connections: green space, street network, stops
- Physical conditions: terrain and slope, sunlight, wind
- Synthesis: one plate that sums up the decisions from the other plates (the only plate with many arrows and notes)
Related guides
Example plates: Geoportal Berlin (dl-de/zero-2.0) · Geobasis NRW (dl-de/zero-2.0) · Datenquelle: LGL, www.lgl-bw.de (dl-de/by-2-0) · © OpenStreetMap contributors (ODbL)