Design procedures in architectural design:

applications in CAAD Richard Hyde

School of Architecture, National University of Singapore, Singapore 0511

Normally, CAAD systems are used at the production end of the design process. Yet there is great potential, particularly with the graphics facility offered by these systems, to use them at the beginning or formative part of the design process.

One problem with this direction lies in the procedures for using these systems. This paper compares traditional procedures for using graphic information with computer-aided procedures and discusses the

relative merits of the approaches for the designer.

Keywords: CAAD, design procedures, graphical thinking, design process models, design eduction

The research described here involves the use of existing software and computer systems aimed at graphic model- ling of architectural solutions. These commercially avail- able software and systems are designed for a wide range of applications but basically the systems aim at com- puterizing manual methods of graphic representation. For example, MacPaint on the Apple Macintosh and the Degas and Neochrome programs on the Atari ST provide tools for sketching and rendering. Other systems such as Autocad provide two-dimensional drafting and some three-dimensional facilities, while some powerful mini- based systems such as Intergraph also allow three- dimensional modelling and surface-shaded rendering.

The use of these latter systems has been predominantly in the production phase of the design process. This has involved producing working drawings, sophisticated perspectives or surface-shaded drawings of the already designed building. The use of sketching programs does not appear to be extensive. Clearly, although these applications are obviously a beneficial aspect of computer-aided design, the potential for using these systems in other parts of the design process remains evident but untested. Moreover, the barriers to doing

this remain ever present. One barrier is the lack of available procedures for

using the systems. The term procedure is defined as the way in which the computer system is integrated into the design process of the architect. Clearly, this is a fairly contentious area: design is seen as a very personal idiosyncratic process and attempts at formalizing methods and procedures are fraught with difficulties 1. Yet, it became apparent that in order to utilize the systems effectively careful understanding of the design process and the procedures that could be used was necessary.

The first aspect that was examined, therefore, was the way the design process could be modelled. This provided the conceptual framework for the research approach.

DESIGN PROCESS AND DESIGN PROCEDURES

Models of the design process

Traditionally, the design process has been thought of as

0142-694X/89/040239-07 $03.00 © 1989 Butterworth & Co (Publishers) Ltd 239

five distinct parts: fact finding, analysis, synthesis, veri- fication and communication. In this process the designer researches the problem area, analyses it for crucial information, synthesizes the information to solve the problem, evaluates the solution to verify its credibility for solving the problem and finally the solution is communicated to a third party for implementation 2. For the purposes of this research, the first three parts of the process were thought of as the formative phases and the last two as the production phases.

In architecture this process has manifest itself in a series of models of design which have evolved and been modified in recent years (see Figure 1). The evolution started with the traditional design process (excluding craft processes), which was primarily design through two-dimensional drawing. In this model information is integrated in the graphic model of the building through

Traditional method: design by drawing

Inception[:> FeasibilityD Sketch designD Working drawings

t $ $ Information Information

Systematic: design by reason

Programmed Analysis D evaluation

? Information package

SynthesisD Refinement

Heuristic: design by discovery

Concepts Programmed Analysisb> or DParti~> basic precedents information package I' I' 1'

Additional information

Refinement

Conceptualization: design by ideas

Programmed ConceptualizationD PardDRefmement

t t Representation Point of

departure

Figure 1. Models of the design process

dialogue between client and architect. The process moves from abstract general ideas at the beginning to more complex refined notions of the building at the end.

As building design has become more complex it has been argued that a more systematic method should be used to analyse and give priority to information through an architectural programming phase (not to be confused with computer programming). Information is collected before design and examined in a non-graphic way to develop goals, objectives and intentions. This is prior to the architect generating the design of the building.

More recently heuristic and conceptual models of architectural design have developed which emphasize thinking processes other than systematics. These methods integrate a wider range of thinking skills in the design process. The notion of heuristics stresses the importance of a priori knowledge in design, the way architects use ideas from the past and adapt them to current problems. Also, conceptual notions structure architectural knowledge into basic concepts which act as generators in the design.

In the latter models the process of design moves away from the earlier paradigms of seeing design as a complex algorithm which solves problems by rational means. Second and third generation design methods stress an heuristic focus to design which relates to the architect's perception and understanding of the design problem 3.

In addition, the way the architect searches and ex- plores possible solutions to the design problem is another important aspect of this approach. In this situation the use of personal insight and creativity can generate a richness of architecture which has been lost with succes- sive methodological and systematic approaches to design 4.

In recent years the latter model of conceptual design has been used in teaching design since it focuses stu- dents' attention on their ideas and less on the process of design. Much of the research worked carried out in this paper is based on this model.

Notes on design procedures

It was apparent that, in examination of the various models of the design process, there is a number of procedures that architects carry out in the design pro- cess. Here, procedures is taken as the operations, tasks and sequences of activities in design development. In fact, in teaching architectural students it is necessary to clearly specify these procedures so that the problem can be quickly and effectively resolved.

For example, at one level it is necessary to identify the media used to explore the design problem. It is recog- nized that at the formative stage sketching is usually used; as the design evolves more precise sketching and solid modelling are used; finally more precise and de- tailed drawing is required 5. This procedure is fairly consistently used. The question arises as to why these media should be used at these places in the design process.

240 DESIGN STUDIES

Many would say that the answer to this is obvious. Precise draf t ing is requi red to communica te the architect's intentions for production purposes and to represent the building to the client. Sketching, on the other hand, allows the architect to be free to explore the creative aspect of the design problem in a loose kind of schematic way.

Both these rationalizations may be true but, if deeper consideration is given, it would seem that it is not just to do with appropriateness of the media to provide for communication or exploration. Other factors are also important and this has to do with the designer's thinking, the concepts considered and the resolution of the design.

From this deeper consideration, it was hypothesized that at the formative part of the design process the designer is working largely in an abstract way with general aspects of the problem, at what could be de- scribed a macro-level to solving the problem. With the resolution of the design comes more specific considera- tions and requirements for more representational images of the solution.

To examine this fully two projects were devised using the Degas Paint program on the Atari ST. In these projects the procedure specified an objective, a technique and concepts to help fulfil the objective (see Figure 2). The research projects described here were carried out by first year students who have few preconceived notions of design and thus have few prejudices toward procedures and the methods used.

Project 1: c o m p o s i t i o n in t w o d i m e n s i o n s

The first project was an exercise to explore compositional ideas. Each student obtained a photocopy of a Chinese painting and analysed it for its formal composition qualities (not its symbolical ideas).

In order to do this the procedure involved decomposi- tion of the painting. An abstraction of this was created in the computer as shown in Figure 3. This was then reconstructed to form another abstraction. Another tech- nique was used here: the cut and paste facility in the program allowed a collaging of aspects in the first composition to form a new abstraction. Again the com- positional concepts were used to develop the design.

PROBLEM 1 -

TWO DIMENSIONAL COMPOSITION

PROCEDURE

Objective Technique

*Deconstruction *Abstraction *Reconstruction *Cut and paste

CONCEPTS

*Simplification *Focus *Balance *Depth *Scale *Contrast

PROBLEM 2 -

SPATIAL FIT

PROCEDURE CONCEPTS

Objectives Technique * Space *Form

• Construction *Abstraction *Functional fit • Deconstruction *Erosion *Light • Construction *Addition *Texture

PROBLEM 3 -

THREE D IMEN S IO N A L COMPOSITION

PROCEDURE CONCEPTS

Objective Technique *Integration *Coupling

*Construction *Addition *Mounting *Scaling *Embracing *Copying *Penetrating *Rotation *Extrusion

Figure 2. Procedures used in the design projects

textures and patterns. In this exercise further concepts were identified and used in the design procedure.

Both these exercises were of very short duration. The time taken to learn the program was about one day, with two to three days to resolve the design.

Project 2: spat ial fit

The second project focused more on architectural design (see Figure 4). It involved the design of a changing room or sauna for a single person. The main constraint was that the space was to be created out of a solid - a square, cone or pyramid. The design exploration was in plan and section. This again involved students with a procedure involving construction, deconstruction and construction again. The techniques involved exploited more of the potential of the computer program, in particular the eraser and the fill capability. These allowed the notional cutting or eroding into the solid and the adding of

F e e d b a c k

Setting aside the architectural and educational benefits found in these projects, it was interesting to see, once the procedures were identified, the ease by which the design could be initiated and the project completed. In the case of the second project, from the schematics developed on the computer further refined drawings were developed using manual techniques.

Feedback from students and observations made during the project indicated that the use of the program at the formative stage seemed effective. A number of observa- tions were important.

Vol 10 No 4 October 1989 241

Finally, it was observed that the computer system in this type of project was facilitating the manipulation of form. That is, the students were primarily organizing the graphic elements on the screen as formal elements of the design problem. It appeared that the computer was assisting with the relationship of these formal aspects of design. The formal aspects, in this context, are the way the form of the design is developed, what shapes are used and how they are composed or related to one another in an abstract way, and what this means architecturally. This direction was examined further.

COMPARISON OF TRADITIONAL DESIGN PROCEDURES AND CAAD APPLICATIONS

The results of the first projects were encouraging and further exploration of manual techniques in the use of graphics in relation to design was considered. This search identified three main areas of thought:

• visual recording • problem solving techniques • design grammars and precedents

Visual recording

Visual recording is aimed at developing an architect's

Figure 3. Composition in two dimensions using the concepts of (a) deconstruction and (b ) construction

First, the students were by and large enthusiastic about the exploration. Many had difficulties with tradi- tional manual sketching techniques; the computer pro- vided a substitute that provided professional, colourful representations which still had a schematic quality.

Second, the students could quickly and easily develop a rapport with the system, i.e. it was found that the system could be used without conscious thought. The computer, like driving a car, requires a high level of proficiency which needs to be reached very quickly so that its use is automatic and concentration can be placed on the task in hand. This level of proficiency has to be reached quickly in order that the use of the system becomes automatic and the flow of ideas is developed on the screen with ease and without interruption.

Third, the one aspect that was found problematic was to do with understanding the concepts. These concepts were some of the source ideas and, without a working understanding, the students had great difficulty develop- ing their design proposition. Some system of data storage of examples for recall would aid this kind of under- standing. Figure 4. Design project using spatial fit concepts

242 DESIGN STUDIES

des ign voc a bu l a r y t h r o u g h drawing of exis t ing architectural works, particularly works of merit s .

The premises for this approach lie mostly in pre- modern design training and are as follows:

• a person's understanding of a building is enhanced by the act of drawing it

• the ability to remember that understanding is en- hanced by having made such drawings

• the ability to draw accurate facsimiles of exemplary works of architecture is proportional to one's efforts to do so

• together these remembered experiences and under- standings contribute the architectural memory that we call upon in order to design

The benefits of this approach feed indirectly through the designer's intuitive thinking into the design process. There are no clearly identifiable procedures for using this knowledge explicitly.

Graphic problem solving

This technique uses graphics to symbolize aspects of the building and aims at the opposite of the first approach. Rather than build a design vocabulary inside the architect's head, it seeks to externalize thinking and make it more rational. This direction comes from sys- tems science in the 1960s and attempts through di- agrammatic means to aid design analysis and synthesis 6.

The problem with this approach is that it is useful more for functional and tangible aspects of the design

process. Clearly it has difficulty in accommodating for- mal ideas in architectural design.

Design grammars and precedents

Design grammars and precedents accede to this formal and conceptual area of design work. With design gram- mars, form in architecture is viewed as a language which has a structure and a coherance - in fact a set of rules. The rules can be implicitly found in buildings which can be used as models. Alternatively the buildings can be analysed and externalized to form grammars 7'8.

Clearly once the formal reltionships in architecture are examined in this way, the procedures for using prece- dents and grammars may be feasibly developed.

TESTING OF APPROACHES IN CAAD

The next aim was to test these three main areas of thought through further research work in CAAD.

Visual recording has involved the three-dimensional modelling of exemplary buildings by famous architects. The procedure for doing this follows recognized author- ities in the field 9 and uses the Intergraph AMOD soft- ware. To some extent this approach has been successful (see Figure 5). Not only can a variety of representations be made but various aspects of the building identified and emphasized. This enables the communication of selective aspects of the building that are important 1°. At present a large number of these models have been created

Figure 5. Modelling of exemplary buildings by famous architects

Vo110No4October 1989 243

but how to use them in the design apart from as an information source remains unresolved.

Graphic problem solving using the computer CAAD systems has not been tested although an Intergraph space planning package is available for this purpose.

The area that has been more directly relevant to the design process has been with the use of the Intergraph AMOD software but simplified for quick, three- dimensional modelling. This usage has drawn on the third area of thinking described above, that of using precedents and grammars. It is worth describing this approach in greater detail.

Project 3: 3-dimensional composition

In this respect the research started by examining various aspects of architectural theory related to grammars and precedents. Most of this work is still either at the early stage of development or historically orientated. What was required was a procedure that followed an abstract generative process since this could be modelled easily on the computer in the form of wire frame diagrams and finally surface rendering.

One fruitful line of enquiry is based on the work of Chernikov, the Russian 'Constructivist', who developed a number of principles for creating buildings based on abstraction. There is insufficient space here to detail this approach but, simply, the procedure starts with viewing the building as a 'non-object'. It is seen as potentially made up of a series of dots, lines, planes and volumes. In the creative process the designer takes these abstract elements and using a set of constructive principles, for example joining and compositional techniques, evolves the form of the building. The building develops by virtue of manipulating elements in relationship to one another in a transformative way to create the building 1~. In fact,

Figure 7. Three-dimensional modelling of Constructivist concepts of penetration

the procedure is highly suited to CAAD as the basic concept of the system has its foundation in Cartesian geometry on which Chernikov and earlier masters like Kandinsky based many of their ideas ~2.

The procedure involved using Intergraph three- dimensional modelling software but simplified to allow ease of utilization (see Figure 3). The objective of the project was to create a simple, three-dimensional com- position using a given set of elements and clearly defined principles. In this case joining principles were used, for example, mounting, embracing, coupling and so on. The project involved manipulating elements such as various types of plane or volumes to create a composition. The outcome of this exploration is seen in Figures 6 and 7.

Feedback

The results of the project showed that the CAAD system could be used to create these kind of compositions within a fairly short space of time. The project took about one week, which included learning the basic commands.

The time aspect is important. In designing, the proce- dure is not one of lengthy protraction and contemplation but is quick and spontaneous. The CAAD system has to facilitate this design approach. Some problems were experienced here but given the technological limitations these were unavoidable.

Figure 6. Three-dimensional modelling of Constructivist concepts of embracing

C O N C L U S I O N

In conclusion, the next avenue of research is to begin to expand the procedure and take it further than just creating abstract compositions in three dimensions. The need to add further considerations such as function and

244 DESIGN STUDIES

context are imperative in this approach. It is important though, at this point, to recognize

certain points. First, it seems imperative that the way to develop

CAAD systems lies in computerizing existing manual techniques. There is also the fact that in the systems themselves lie inherent potentials that can be utilized in the design process. For example, the manipulative func- tions such as scaling and copying allow numerous options for transforming form.

Second, in order to realize these potentials new design procedures have to evolve. At present the research described here has utilized existing architectural theory as a basis for development. It is likely that this aspect, linked with some form of knowledge-based system which are currently being developed, may provide a very useful design approach 13.

Third, it became apparent that the effective use of the CAAD system lies in the development of correct proce- dures for design development. This factor should be coupled with providing a level of friendliness that allows the designer the same level of rapport with the system as can be found with the pencil and paper.

R E F E R E N C E S

1 Lam, K P and Hyde, R A 'Wrestling with the productiv- ity curve' Proceedings of Ausgraph 87 (1987)

Broadbent, G Design in architecture, John Wiley, Chiches- ter, UK (1973); Jones, J C Design methods, John Wiley, Chichester, UK (1980)

Grant, D 'Aims and potentials of design methodology' Design Methods and Theories Vol 20 No 1 (1986) pp 389-394

4 Hyde, R A 'Problems of method: the evaluation of

10

11

12

13

conceptual design for beginning students' forthcoming in Design Methods and Theories (1989)

Crowe, N A and Hurt, S W 'Visual notes and the acquisition of architectural knowledge' J.A.E. Vol 39 No 3 (1986) pp 6-16

Lassau, P Graphic thinking for architects and designers, Van Nostrand Reinhold (1982)

Stiny, G N 'Computing with form and meaning' J .A.E Vol 38 No 2 (1985) pp 7-19

Wojtowicz, J and Fawcett, W Architecture: formal approach, Academy Editions (1986) pp 23-35

Mitchell, W 'The electronic Atelier - graphics, networks and the exploration of architectural ideas' The Proceedings of Architect's Computer Conference Singapore (1986)

Schiff, R 'Strategies for CAAD education - the Singapore way' in CAAD Futures, Einhoven (1987) pp 1-20

Papadakis, A AD Profile 55 Vol 54 No 9-10 (1984) pp 21-23

Kandinsky, W Point and line to plane, Dover Publications (1928) pp 7-13

Jens, P et al. 'ICADS: an intelligent computer-aided design system' Design Methods and Theories Vol 1 (1988) pp 749-794

A C K N O W L E D G E M E N T

The research projects were funded by the National University of Singapore. The author would also like to recognize the assistance of Mr Ong Boon Lay, Ms Dorothy Lim, Mr Bernard Teo, fourth and first year students of the School of Architecture, National Uni- versity of Singapore, in carrying out the projects.

Vo110 No 4 October 1989 245