UNDERSTANDING ORTHOGRAPHIC PROJECTION DRAWINGS

The practice of interior design requires the creation and use of various types of drawing. These can be divided into three broad categories based on purpose. The first type of drawing allows the designer to explore ideas (known as ideation) and work conceptually, often in the form of sketches. The second type allows the designer to communicate to others, including members of the design team, the client, end users, consultants, and other professionals (presentation drawings). The third type of drawing conveys the technical information required for construction (construction documents or working drawings).

This book focuses on the first two types of drawing, those used for exploration and presentation or graphic communication of ideas. Unlike ideation sketches, presentation drawings and construction documents must Design drawings are highly standardized so that they carry universal meaning. Or, as one early reviewer of this book put it, “Design drawing is much like a language; the drawings must convey the designer’s meaning clearly.”

The design drawings most commonly used in scaled delineation of interior environments are floor plans, interior elevations, sections, and reflected ceiling plans. These drawings, called ORTHOGRAPHIC PROJECTIONS, are created by projecting information about an object onto an imaginary plane known as the PICTURE PLANE. This direct projection of an object’s dimensions allows orthographic projections to retain shape and proportion, making these drawings accurate and precise.

Orthographic projection creates fragmentary views of an object, resulting in the need for multiple drawings. This means that because of their fragmentary nature orthographic projections become parts of a system and are mutually dependent on one another. By their nature, orthographic projections
appear flat and lack the three-dimensional quality of perspective drawings. One way to visualize orthographic projection is to imagine an object enclosed in a transparent box. Each transparent plane of the enclosing box serves as the picture plane for that face of the object.

The view through the top plane of the enclosing box is called a PLAN. In a plan view only those elements seen when looking directly down at the object are drawn. Figure 1-3 depicts a roof plan.
The views through the picture planes that form the sides of the enclosing box are called ELEVATIONS. Elevations depict only what is visible when viewed directly through the picture
plane.

A SECTION portrays a view of the object or building with a vertical plane sliced through it and removed. One way of understanding section views is to imagine that a very sharp plane has been inserted into the object or building, cutting neatly into it and revealing the structure and complexity of the object’s form. A floor plan, also known as a horizontal section, portrays a view of the building with a horizontal plane sliced through it and removed, exposing the thickness of the walls and the elements below the cut line such as floor finishes and furniture.