What best defines a floor plan in building drawings?

• A. A cross-sectional view taken on a vertical plane.
• B. An elevation view of the exterior.
• C. A sectional view taken on a horizontal plane 42 to 48 feet above the floor.
• D. A plan view of the roof only.

Answer: (C)

A floor plan is a horizontal cut through a building that shows the layout of rooms, walls, doors, and windows as seen from above. The cut is made at a height above the finished floor—typically around 42 to 48 inches (about 3.5 to 4 feet)—so you can clearly read the interior arrangement and how spaces relate to one another, including door swings and fixture placement.

This is why the described option is the best: it identifies a horizontal sectional view taken high enough above the floor to reveal the interior layout, rather than a vertical cross-section, an exterior elevation, or a roof-only plan. The other views depict different aspects (height-wise construction details, exterior faces, or the roof) and do not represent the interior floor layout.