The site analysis and preparation of the design program are two other tasks undertaken in the research and preparation phase of the design process. The purpose of the site analysis, also referred to as site study, is to identify all the vital site conditions and determine how they might influence the eventual design solution. During the site analysis, the designer should become as familiar as possible with the site so a design solution can later be developed to suit the particular conditions of the site. The design program, which is usually prepared after the site study is completed, is the culmination of the research and preparation phase. The design program is an outline of all the elements and requirements that must be included in the design and provides the basis for the beginning of the design phase.
Before proceeding, it is important to understand that there are two distinct steps of the site study: (1) inventory and (2) analysis. Site inventory is the gathering of facts and information about a site. It identifies and records the location, size, material, and condition of existing site elements such as walkways, terraces, fences, utilities, and plant materials. The inventory also records other aspects of the site such as soil type, degree of slope, location of utilities, prevailing wind directions, sun and shade patterns, specific views of importance, and so forth. In other words, the site inventory is data collection.
Site analysis, on the other hand, is an evaluation of the information obtained in the site inventory. Site analysis makes judgments about this information and determines how the design solution should respond to these conditions. For instance, how should the proposed design relate to an inviting view of a stream just off the site? How might the buried cable line affect the layout of the front yard? How should the design of the terrace respond to the direct exposure to the hot afternoon sun? What plant materials should be retained and incorporated into the proposed design?
In theory, site inventory precedes site analysis because it necessary to collect the facts before making judgments about them. However, the reality is that the two steps often overlap, especially for experienced designers who can quickly and instinctively envision responses to various site conditions. For the inexperienced designer, the problem is often stopping at site inventory and not doing a thorough site analysis. It is difficult to understand the potential consequences of different site conditions
without prior experience of dealing with them. Nevertheless, it is vital for all designers to methodically go through each step in order to have a complete understanding of the site as the basis for a landscape design.