Principles

Axis

An axis is the most basic means of organizing forms and spaces in architecture and interior design. It is defined as a line established by two points in space that allows for forms and spaces to be arranged around it in a regular or irregular manner. An axis is imaginary and not visible except to the mind’s eye. It implies symmetry but demands balance. Because it is linear, it has characteristics of length, direction, and movement.

For an axis to be an axis, it must be terminated at both of its ends by a form or space. The terminating forms and spaces of an axis serve as visual force. The different types of terminating forms and spaces for an axis include points in space, vertical planes, well-defined spaces, and gateways that open toward a view. See below a diagram of vertical planes being used terminating forms and spaces for an axis.

For instance, in the interior below the hallway acts as the axis while the door (vertical plane) and bathroom (well-defined space) act as terminating forms and spaces for the axis.

Photo: Joss, Main. Marvelous Home Interiors. (2014).

Overlay: Mine

Symmetry

Symmetry cannot exist without an axis or center about the structure that is symmetrical. It requires forms and spaces to be arranged in a balanced and equivalent way on opposite sides of an axis.

The two types of symmetry are bilateral symmetry and radial symmetry. Bilateral symmetry is symmetry that occurs from the balanced arrangement of equal elements on opposite sides of an axis that only one plane can divide the whole into two halves. Radial symmetry is defined as the balanced arrangement of equal radiating elements so that the composition can be divided into halves from an angle as long as it stays on the central axis. See below a diagrammatic example of bilateral symmetry.

Below is an example of bilateral symmetry in architecture (Taj Mahal).

Photo: Taj Mahal, India.

Overlay: Mine

Hierarchy

Hierarchy in architecture is defined as the differences between forms and shapes of an organization that make certain forms and spaces more important than the others surrounding it. The differences reflect the functional and symbolic roles each form and space plays in an organization. For a form or space to appear significant, it must appear visually unique by size, shape, or placement.

Hierarchy by size is when a form or space dominates an architectural composition by being significantly different in size from all other elements in the composition. Hierarchy by shape is when a form or shape can be distinctly picked out amongst other forms and shapes because it is a different shape than the others. Hierarchy by placement is when a form or space is placed in a certain spot among the other forms and spaces surrounding it to make it stand out. See below a diagrammatic example of hierarchy by shape.

Below is an example of hierarchy by shape in architecture.

Photo: Georgia Capitol Building

Overlay: Mine

Datum

A datum is a line, plane, or volume that serves as a reference that other elements in a composition can relate to. Its purpose is to organize a random pattern of elements by maintaining regularity, continuity and constant presence. Because an axis has the ability to organize elements along its length, it serves as a datum. However, datum is not restricted to being just a straight line. It can also be a plane or volume.

A linear datum cuts through patterns and forms a common edge organize the elements. A planar datum organizes elements by gathering them underneath it or acting as an encompassing background for elements in front of it. A volumetric datum collects the elements within its boundaries and also organizes elements along its perimeter. See below a diagrammatic example of a planar datum.

Below is an example of linear datum being used in architecture and urban planning.

Photo: Lyon Presquil, France

Overlay: Mine

Rhythm & Repetition

In architecture, rhythm refers to any patterned recurrence of elements at regular or irregular intervals. Rhythm is used in repetition to organize forms and spaces in architecture. Elements in a composition are grouped according to their closeness or proximity to one another and the visual characteristics that the elements have in common. Repetition uses both of these concepts to order repeating elements in a composition. Elements can vary by size, shape, or their detail characteristics so long as they repeat in some sort of fashion. See below a diagrammatic example of repetition of elements that vary by size but are still organized by repetition.

Below is an example of repetition being used in architecture.

Photo: Mayakovskaya Metro Station, Moscow

Overlay: Mine