Chapter 8 discussed how functional diagrams are used to establish the overall functional and spatial organization of a design during the first step of the design phase. The organization of all these factors in a functional diagram furnishes the structure and foundation for the next step of the design process: preliminary design.
Preliminary design starts with the functional diagram and ends with an illustrative site plan, which may be supplemented with sections, elevations, and perspectives depicting all the elements of the design in a semirealistic graphic manner. To complete a preliminary design, the designer examines three interrelated factors. The first is careful consideration of the aesthetic organization and appearance of the design based on knowledge and application of three basic design principles: order, unity, and rhythm. These principles help the designer create a visually pleasing design solution.
The second factor, called form composition, is the study of the exact location of all two-dimensional edges and lines of the design. The designer accomplishes this by converting the approximate outline of spaces developed earlier in the functional diagrams to specific two-dimensional forms. This step begins to establish the visual style or theme of the design.
The third factor examined in preliminary design is spatial composition. Spatial composition is the third dimension of outdoor rooms that are based on the foundation of the form composition. The designer uses grading (landform), planting, walls/fences, steps, overhead structures, and so on, to complete the total environment of the design during this step.
The objectives of this chapter are to (1) discuss the definition and purpose of a preliminary design, (2) outline the process for developing a preliminary design, and (3) discuss the basic principles of design. The other important aspects of preliminary design are discussed in Chapter 10 (form composition) and Chapter 11 (spatial composition).