Bubble diagrams are about relationships
A bubble diagram is simply a way of showing how rooms relate to one another. There is no need to overthink it or force it into a literal image. If two bubbles are connected, it means the spaces have some kind of relationship. That relationship may be serial or parallel, so rooms can interact directly, or they may just sit next to each other with a corridor, hall, or other circulation node linking them.
A two-way arrow often suggests that the traffic connection may form a loop.
At the same time, if two rooms are not connected on the bubble diagram, does that automatically mean there is no relationship? Not necessarily. Other information may still prove that the two should be linked, so the missing connection has to be completed based on the text and the whole problem statement.
This kind of judgment only becomes reliable through repeated practice with real exam questions.
When reading a bubble diagram, it also helps to look at the building’s external conditions: public versus private zones, daylight and ventilation, views, and entrances. These factors all affect how the functional rooms should be arranged in relation to one another.
Start from the big picture and work inward
The key is to think in layers: first find the relationship, then move from macro to micro, from the whole to the part.
A bubble diagram expresses the logic of spatial organization. It shows how different functional spaces interact and connect, and it does so in a layered way.
For serial connections, the required strong sequence in the problem must be achieved. The main circulation line must stay continuous and cannot be broken. In terms of spatial combination, rooms should be adjacent, aligned, or otherwise matched according to the textual clues.
Group similar items together
Items with the same nature, area, function, type, boundary, or number should be grouped together and handled as a whole instead of one by one.
This is really a matter of relational thinking: use the same logic to analyze the same kind of element, and solve a class of problems through one clear point.
- Overall level: site plan
- Vehicle flow: when pedestrian and vehicle circulation must be separated, the driveway and walkway should be divided by a green belt, not placed side by side. Where people need to cross, the green belt should be opened.
- Greenery: areas along the site boundary can be circled. Internal green areas usually do not need to be circled, both to save time and because they are harder to draw neatly.
- Plaza: a gathering square usually connects one end to the municipal road and the other end to the building.
Site plans should generally be completed within 15 minutes, so repeated practice is essential.
Circulation inside the building
Building circulation follows three basic principles: keep the route as short as possible, avoid unnecessary detours, and prevent intersections. In this context, circulation design is more of a common-sense issue than an analytical one — the arrangement simply needs to make logical sense.
There are exceptions that need to be justified. For example, in an airport, transfer passengers and boarding passengers may cross paths. That kind of overlap can only be used after a convincing explanation. It is also worth noting that these are tidal flows: people gather in concentrated periods rather than constantly moving all the time, so even if the routes intersect, they do not actually conflict in use.
Be willing to create space. Once the rooms have been laid out, any leftover area can often be turned directly into circulation space.
Three kinds of traffic space
Traffic spaces can be divided into vertical circulation, horizontal circulation, and hub circulation.
Horizontal circulation should stay closely tied to the overall spatial organization. It needs to be direct and smooth, without excessive twists and turns, and it should also have decent ventilation and daylight.
Horizontal circulation spaces can be understood in several forms:
- Pure circulation spaces such as passageways, entrance halls, and corridors.
- Circulation spaces that also serve other functions, such as a wide corridor in an outpatient clinic.
- Corridors and halls used for multiple functions at once, such as the display hall in an exhibition building.
Common corridor types include single-loaded external corridors, internal corridors, double-loaded corridors, cloisters, large hall-type layouts, and mixed forms such as a hall combined with office space.
Sensitivity to numbers
For large rooms or large spaces, pay attention to how standard and non-standard numbers are handled. Standard numbers should generally remain unchanged. Non-standard numbers can be adjusted up or down, or smaller rooms can be combined to form a standard size.
When comparing upper and lower floors, numbers that match and serve the same function should be aligned first.
Wall boundaries and column grids should also be aligned whenever possible.