Which plan illustrates the vertical relationship of spaces in a building?

The elevation plan is the correct choice for illustrating the vertical relationship of spaces in a building. Elevation plans present the external view of a structure from a specific viewpoint, showing the heights and proportions of different sections of the building. They help in visualizing how various elements relate to one another vertically, such as the height of windows, doors, and the overall roof line. This is essential in understanding how the various levels of a building interact with each other regarding vertical spacing.

In contrast, other types of plans serve different purposes: the floor plan is primarily concerned with horizontal layout and spatial arrangement of rooms; the site plan focuses on the building’s placement in relation to its surroundings; and the section plan, while showing a cut-through view of the building, does so in a way that illustrates internal relationships rather than external vertical relationships. Each type of plan has its specific use cases, but for understanding vertical relationships, the elevation plan is the most appropriate choice.