A plan view is a top-down representation produced by projecting a three-dimensional object onto a horizontal plane. In technical drawing and architecture this is a type of orthographic projection in which a notional horizontal plane is used to cut the object and the parts above that plane are omitted or shown differently so that interior or underlying features become visible.
Characteristics and conventions
Plans are typically drawn to scale and oriented with a consistent direction (often north in site plans). A plan may be produced at different cut heights depending on purpose: for example, a plan cut through windows will show door and window openings differently than a plan cut near the ceiling. Conventional symbols, line weights and hatch patterns indicate walls, openings, fixtures and materials. Hidden or overhead elements are shown with dashed lines or separate annotations.
Relationship to sections and elevations
A plan is closely related to a section and an elevation. A section slices the object vertically to reveal internal structure, while an elevation shows a façade from a straight-on viewpoint. Together these views give a complete orthographic description of form without perspective distortion.
History and development
Top-down plans have been used for centuries in architecture and engineering to communicate layout and construction intent. From hand-drawn building plans to modern CAD and BIM, the basic idea—representing horizontal relationships and dimensions from above—remains unchanged even as symbols and tools evolve.
Uses and examples
Common examples include the architectural floor plan that shows rooms and circulation, mechanical part drawings that show hole patterns and mounting points, and site plans that place buildings within landscape context. In a residential plan the roof and upper portions of walls are often omitted to make the interior arrangement clear.
Notable distinctions
- Plan (top view) vs perspective: plans preserve true scale and dimensions, while perspective views simulate human vision.
- Plan vs elevation: plans show horizontal relationships; elevations and sections show vertical relationships.
- Cut height matters: different plan heights serve different disciplines (architecture, structure, MEP).
Well-drawn plan views communicate spatial layout, dimensions and relationships efficiently and remain a fundamental tool across design, construction and manufacturing disciplines.