Previous sections of this chapter have focused on the design themes that can be used on a residential site and some of the basic geometric principles on which these themes are based. Yet, the process for selecting and developing form composition studies for a residential site is more complex than just drawing attractive forms. The process should involve a simultaneous consideration of (1) geometry of form, (2) desired feeling or character of the design, (3) relationship to existing structures, and (4) relationship to the functional diagram. A good form composition is a sensitive blending of all these factors.
To begin the process of form composition, the designer starts with a functional diagram. Next, the designer selects a design theme or combination of themes. This decision should be based on (1) desired character and/or style of the design (that is, formal or informal, relaxing or stimulating, contemporary or historic, and so on), (2) appropriateness to the architectural style of the house, (3) appropriateness to the existing site conditions, and (4) preference of the clients.
Once a design theme is chosen, the designer is ready to start the process of developing a series of form studies. The two critical steps in this process are (1) relating the proposed design forms to the existing structures, and (2) relating the proposed design forms to the functional diagram. Although these two steps should take place at the same time, they will be discussed separately in the following paragraphs.
Relationship of Form Composition to Existing Structures With few exceptions, almost all residential site designs are developed in association with either existing or
proposed structures, such as the house, garage, storage shed, gazebo, walks, terraces, or walls. Existing structures should influence where lines and edges of spaces are located on the site so they blend in with the proposed design and the final result is a visually coordinated and unified residential environment. When done appropriately, it may be difficult to distinguish between what originally existed on the site and what was added.
This objective can be accomplished by relating the edges of new forms with the edges of existing elements or structures. To do this, the designer should first obtain a copy or print of the base sheet, which shows existing structures to be retained. On this copy of the base sheet, the designer should identify the prominent points and edges of the existing structures. For an existing house, there is a hierarchy of points and edges that should be considered:
1. Primary importance: outside walls and corners of the house (Figure 10—68).
2. Secondary importance: edges of elements on outside walls that touch the ground surface such as edges of doors or lines created by material changes (between brick and siding, for example, Figure 10—69).
3. Tertiary importance: edges of elements on outside walls that do not touch the ground surface, such as windows that are above the ground (Figure 10—70).
The next step is to draw lines on the base sheet from these prominent points and edges into the immediately surrounding area of the site (Figure 10—71). A color pen or pencil is suggested so that the lines are easily distinguished from other lines on the base sheet. These three sets of lines are referred to as lines offorce because they guide or force a connection between existing and proposed compositional forms. The lines of primary importance have been drawn darker for emphasis. In addition, other lines have been drawn to create an overall grid system. These other lines were drawn perpendicular to the original set of lines of force at a selected interval. For instance, the distance X between lines A and B has been repeated away from the house to establish the location of lines C and D. In the backyard, the distance Y has been used to space
the lines of force, with some lines, such as G and H, being a distance 1/2 Y apart. No rules govern the spacing of these additional lines.
After the lines of force and grid system have been drawn on the base sheet, the designer should overlay a sheet of tracing paper on top of the base sheet. A form composition study can be prepared on the tracing paper (1) in coordination with the lines of force and grid system beneath, and (2) in relation to the functional diagram (explained in the next section). An example of a form composition study that has been
created based on the lines of force without having it relate to a specific functional diagram is shown in Figure 10—72. Several things should be apparent from this example. First, a rectangular theme can easily be developed using a 90-degree grid system. Second, the grid is used as the foundation for the form composition over the entire site, not just near the house. Yet, at several places, such as the front entry and the back terrace, the edges of the forms have been located between the lines of force. The designer should not feel obligated to draw all the edges of forms—only where there are lines of force.
The designer does not always have to use a grid system that has a 90-degree relation to the house. As seen in Figure 10—73, lines of force can be extended away from the house in any direction. In this example, the lines of force and grid system were drawn on a 45-degree angle in relation to the important points and edges of the house. Then, other lines based on a repetitive distance were added to formulate the grid. Following this, the diagonal form composition theme was drawn in response to the grid system.
Grid systems can also be used to aid in creating other design themes. One possibility is to combine the 90-degree and 45-degree grid systems to develop a modified diagonal design theme. The 90-degree or 45-degree grid system can be used as the basis for an arc and tangent theme. The grid system is most useful for rectangular, diagonal, angular, or arc and tangent design themes, because they incorporate straight lines. The lines of force and grid system have limited use for the circular and curvilinear design themes (Figure 10—74). These latter schemes might relate to a particular point or edge of an existing structure, but on the whole they are difficult to correlate to a grid system. Consequently, the grid system, except for perhaps the primary lines of force, can be dispensed with while developing circular and curvilinear design themes.
What is important in the circular and curvilinear design themes is how the lines and edges in the site connect with the sides of the house and other straight edges. Every possible attempt should be made to avoid acute angles or other awkward visual relationships in the transition areas between new forms and existing structures. In Figure 10—74, most of the circular arcs meet the house at 90 degrees. When there is not enough room for an arc to meet at a 90-degree angle (left of the driveway), then the connection should be greater or equal to a 45-degree angle. Remember, avoid acute angles.
Several points must be kept in mind while drawing the grid system for the form composition. First, this grid system is drawn to provide guidelines or clues for locating the edges of the new forms in the design. When the edges of the new forms are aligned with the points and lines of the grid system, the new forms will have a stronger visual relationship to the points and edges of the house. The result is a coordinated integration of house and site. Yet, there is nothing wrong if some of the design’s points and edges do not align with the exact lines of the grid system. The grid system developed through the use of the lines of force is only a helpful tool and not an absolute necessity for the location of all new forms. The grid system is by no means a magic formula that ensures success.
The lines of force and grid system are most important for aligning the forms of the design near the house or other structures and are much less significant farther away from structures. The visual association between the site and any structure is greatest immediately around the structure. In this area, it can be readily seen whether or not the edge of a form in the site aligns with the corner of the house or edge of a door. But as distance increases away from a structure, it becomes more difficult to notice and appreciate any coordinated alignment between the structure and site.
Because the lines of force and grid system are only hints or clues, there is no absolute right or wrong way to establish them on the site. Given the same site and a handful of different designers, each would be very apt to place a slightly different grid system on the site. Although the primary lines of force would probably be the same, the other lines might vary substantially from one designer to the next. A suggestion is to locate only as many lines in the grid as will eventually prove useful. Too few may not suggest anything to the designer; too many may be too confusing.
Relationship of Form Composition to the Functional Diagram In addition to relating to existing structures on the site, the new forms of the design should also relate to the selected functional diagram completed in the previous step. This functional diagram or concept plan also serves as the foundation for the development of the form
composition. Remember, the objective of the form composition phase is to convert the generalized or rough outlines of the functional diagram to specific edges.
The procedure for developing the form composition studies in relation to the functional diagram begins by placing the functional diagram over the base sheet that has the lines of force and grid system drawn on it. Next, a clean sheet of tracing paper, on which the first form composition study will be developed, is overlaid on top of the diagram (Figure 10—75). This permits the designer to see through the tracing paper to the functional diagram and grid system and use them as references (Figure 10—76).
Using the functional diagram and lines of force as bases, the designer next begins to convert the outlines of the bubbles in the diagram to specific edges using one of the design themes. An attempt should be made to relate the new design forms to both the functional diagram and the lines of force and grid system that are on the base sheet. The form composition can be thought of as a careful and coordinated marriage of the lines of force and the functional diagram. This process is not easy because there is much to consider. And the result may not exactly reflect either the lines of force or the functional diagram. Figure 10—77 shows a modified diagonal form composition, using some of the lines of the grid system but also adding others. At the same time, the edges of the form composition approximate the outline of the functional diagram underneath, though again there are some variations.
In relating the new design forms to the functional diagram, the designer does not literally trace the diagram’s bubbles. Instead, the diagram may be thought of as providing hints or approximate guidelines where the edges of the form composition may be positioned. Thus, where necessary, the designer should take the liberty of slightly altering the position of the edges to relate to the lines of force and to establish pleasing form relationships. But the overall size, proportion, and configuration stay generally the same as originally drawn on the functional diagram.
The first attempt at this will no doubt be rather rough, with a number of flaws. Another sheet of tracing paper can then be overlaid on the first sheet so that the first form composition study can be refined. Several attempts and refinements on tracing paper may be needed before the designer is satisfied with the results. And again, the development of alternatives is highly encouraged. The first and obvious solution may not be the best, a fact the designer may not see until the solution is compared and tested with alternatives (Figure 10—78). This overlay process should continue until the form composition is attractive as well as practical.
Now, perhaps, the significance of functional diagrams discussed in Chapter 8 can be better appreciated. A sound functional diagram will result in a form composition that also possesses a solid functional basis. Unfortunately, weaknesses of the functional diagrams are also apt to be continued. So again, it is critical that the designer take the necessary time to adequately study the functional diagrams to prevent organizational flaws from becoming a problem in later phases of the design process.
When developing form composition studies in coordination with the functional diagram, it is quite possible that the designer may formulate a new idea for the design’s organization that is better than the original functional diagram. When this occurs—and it will—the designer should feel free to build on the better idea. The designer may go back to the functional diagram stage to make improvements and then return to the form composition phase.