Detail drawings should reference the building cross section. Which option best represents this reference?

• A. Site plan
• B. Plan view
• C. Building cross section
• D. Elevation

Answer: (C)

When detailing, you need a view that reveals what happens from top to bottom inside the wall or assembly—the layers, thicknesses, and how parts connect through the depth. A cross section accomplishes this by slicing through the building, showing hidden components like studs, insulation, sheathing, and the relationships of joints and fasteners as they pass from one surface to another. That vertical, internal perspective is essential for accurately conveying how the detail is constructed and how it sits within the structure.

In contrast, a plan view is only a top-down layout, so it misses the vertical relationships and material makeup. An elevation shows exterior faces, not the internal composition. A site plan places the building in its surroundings, which isn’t useful for illustrating how a detail relates to the building’s internal depth. Hence, referencing the building cross section is the best choice for detailing.