Architectural Innovation as an evolutionary process


Ing. Roel Daru, Arch. HfG

Associate Professor Design Morphology

Department of Architecture, Faculty of Architecture, Building and Planning Eindhoven University of Technology, Eindhoven, The Netherlands



Is architecture submitted to evolutionary processes? Does that inevitably result in innovations? And if architecture is subjected to the forces of evolution, is this the case with the processes of designing and/or with its results? In order to investigate these questions, we have clarified the concepts used. About what is meant by innovation, evolution and memes and other derived concepts. But after we have developed some preliminary conceptions about evolution, innovation, memes and so on, how can we then study those phenomena in architectural practices? To investigate it in an explorative way, an appropriate case study was looked for, identified and carried out as an empirical basis to collect informations. In order to structure the observations in the case study, a coherent framework was looked for and found in the work of three authors about creative designing. The framework is extended to accommodate the anticipated and distinguished Darwinian and Lamarckian evolutionary processes of architectural design. The information from the case study is applied to the framework in order to check its validity. The information content residing in (and flowing through) the framework is analysed in order to discover how the information units (the memes i.e. copyable ideas, beliefs, behaviours, procedures and so on) infect or penetrate in minds, diffuse or spread over minds and how they are copied, imitated and tranformed by individual minds. In concluding remarks, a preliminary answer is given to the question asked at the beginning of this exploratory study: architecture can be submitted to evolutionary processes and those processes can lead to innovations.

Keywords : evolutionary design, generative grammar, generative art, genetic art, architectural innovation, memetic diffusion, penthouses, roof-top buildings, Dutch architectural design, creativity, Darwinian processes, Lamarckian processes.


Traditionally in art and architectural history, innovation is treated as a history of ideas of individuals (pioneers), movements and schools. The monograph is in that context one of the most used forms of scientific exercise. History of architecture is then mostly seen as a succession of dominant architectural paradigms imposed by great architectural creators fighting at the beginning against mainstream establishment until they themselves come to be recognised. However, there have been attempts to place architectural innovation and creativity in an evolutionary perspective. Charles Jencks for example, has described repeatedly the evolution of architectural and art movements according to a diagram inspired by ecological models [1]. Philip Steadman, in his book “The Evolution of Designs. Biological analogy in architecture and the applied arts” [2] sketches the history of various biological analogies and their impact on architectural theory. However, Steadman has confined his study to a literature survey as the basis of a history of ideas. Since this pioneering work, new developments like Dawkins’ concept of memes [3] allow further steps in the field of cultural evolution of architectural innovation. The application of the concept of memes to architectural design has been put forward in a preceding “Generative Art” conference  by the author [4]showing its application in a pilot study on the analysis of projects of and by architectural students. This first empirical study is now followed by a study of ‘real life’ architectural practice. In this case study generative grammars of architecrural forms are applied and discussed. The case taken has a double implication for the evolutionary analogy. It takes a specific architectural innovative concept as a ‘meme’ (or a whole complex of memes, called memeplex) and develops the analysis of the lineages of this meme in the individual context of the designer and at large. At the same time, the architect involved (Eric Vreedenburgh, Archipel Ontwerpers) is knowledgeable about the theory of memetic evolution and is applying a computer tool (called ‘Artificial’, see addendum) together with Remko Scha, the authoring computer scientist of the program who collaborates frequently with artists and architects. This case study (about roof-top buildings in Dutch town planning and the application of ‘Artificial’) shall be discussed in the paper as presented. A framework will be presented to account for not only Darwinian but also Lamarckian processes, and for individual as well as collective transmission, consumption and creative transformation of memes (in the following wherever the word meme is used, it can also be understood as memeplex).

1. Innovation & evolution

Innovations are the implementations of creative artistic expressions and/or technical inventions. Case studies should be carried out to investigate those intermingled activities of expressions, inventions and innovations. The generative approach is taken to examine in particular design processes where the production of variants (or even alternatives) is at stake. Combined with a selective retention system, a Darwinian process of evolution will be set in motion irrevocably. This Darwinian evolution system is contrary to the usual design process, where the focus is on finding one feasible solution as fast as possible and then elaborate it in depth to the end of the design process. That is, if no unsurmountable problem(s) prevent the continuation of the chosen trajectory. This last procedure induces a Lamarckian process of evolution. Both evolutionary processes are applicable to designing as a cultural activity. The case study delivers some insights about what does exist in at least one practice with a reputation of being innovative. Innovative in the sense that the design office is using (among other diversity breeding techniques) a generative program (called ‘Artificial’) for the variety production of roof-top buildings (in all sorts of settings) with expressive and inventive characteristics. The traditionally accepted roof-top solutions with classical building techniques are in a locked-in situation: a trajectory difficult to break from. What is done by Eric Vreedenburgh as the architect-designer of the new type roof-top buildings is to force a bifurcation point within this trajectory, and choose the alternative way towards a typological tree of developments of prefabricated, light weight penthouses.

1.1 Studying innovations as processes and as systems

There are several approaches to study innovation in general and case studies in particular. Sociologists, economists and historians have given their attention to the phenomenon of innovation, but so have policy and management researchers and researchers from art, design, anthropology, geography, archeology and medicine. However, at least two main approaches emerge from all those studies: innovations conceived as processes and innovations seen as systems. As processes, the study of innovations is geared towards people involved as creators, inventors and mediators, working in an environment tormented by chaotic events, confusion and conservatism. As systems, the measure of succes of innovations depends on the social relationships or culture of cooperation of the people, organisations and authorities involved. Bluntly formulated: in the process approach coincidences are steering innovations, while in the systems approach of innovations, nothing is left to chance.

1.2 Innovations as Darwinian processes of evolution

To investigate innovations as processes there are again at least two views: an evolutionary view of longer duration and a psychological, more modest, shorter term view.

In the Darwinian evolutionary outlook, fundamentally innovative developments are driven by chance, as a result of environmental selection of evolving populations of variants (that is, possible solutions). According to this perspective, basic innovations depend upon accidents, coincidences, chance hits, strokes of luck. But in design and development this happens only to people with an open mind and prepared to see the significance of what is produced. These types of innovations are the result of tortuously surfing the turbulent waves, whirls and eddies at the edge of chaos. From this point of view, radical innovations cannot be driven by markets or managers eager to steer creative processes of innovation. These processes of innovation are unmanageable and permanently getting out of control. But as Darwinian evolutionary processes they might still be seen as opportunities to innovate by exploiting the possibilities of chance and survival. The principle of evolving or replicating designs is set in motion with the combined installation of blind variety and selective retention. That is, the introduction of a diversity production and retention mechanism, together with the application of a selective environment. This results in a process of a survival of the most fit exemplars (design solutions). With these Darwinian driving forces near-maximal efficiency is realizable in the long run of generations of designs. (For an elaboration within the case study, paragraph ‘FRAMEWORK’, 4.2).

From the point of view of psychological decision studies (Simon[5]), we know that the creative, innovative capacities of people are restricted. They are limited in their rationalityand make frequent mistakes. They are also opportunistic and react often only in their own interest. Users are often not able to formulate their needs, in most cases they do not know what is possible technically and they are even in the short run too capricious and inconsistent with their opinions. That makes also predictions about both innovations and markets difficult if not impossible. But innovation are still needed to survive in a changing world. Humans proceed usually along an addaptive learning strategy instead of following the wasteful Darwinian way of producing masses of descendants of whom very few will survive,

1.3 Innovations as Lamarckian processes of evolution

From a Lamarckian point of view, innovations are driven by shifting environments. On the one hand the environment is instructive. The surroundings have direct effects upon organisms (and in extension also designed object). On the other hand, the organisms (or objects) are striving or responding and adapting themself in a creative way to the the shifting constrains, opportunities and required performances of their environment. This is called the instructional theory of evolution and is contrary to Darwinism with a selective theory of evolution (blind variations selectively retained). In design terms, the designed objects are imagined and innovated by the designer as the instructive environment (frequent use develops things, disuse causes them to fade away). Seen in this way, innovations might be instructed: planned deliberately by the designer in the roles of both environment and responding design object. Designing in a Lamarckian way means zooming in as fast as possible to one preliminary but feasible solution and then test and improve that solution as long as is felt to be needed and sensible. In this view there is no need for chances or strokes of luck. In principle this comes down to a rational strategy, based on necessities and opportunities as a basis for decisions. Besides, the flexibility of organisations to innovate and of markets to absorb innovations is also limited. This is due to the lock-in phenomenon: the inability to change from weared technological tracks of old, well known customs and practices which stiffle or paralyze people or organisations. The best way to overcome this conservatism, this barrier to innovation, is a step by step approach, a pluralistic, decentralized  strategy. As Quinn [6] has remarked within this innovation driven process of management, there should be chaos within guidelines. In the short run of one or a few design cycles ‘satisficing’ innovative designs [5] will still be possible based on a mix of both rationality and chance. (For an elaboration within the case study, see paragraph ‘FRAMEWORK’, 4.3).

1.4 The system view of innovations

In studying innovations as systems, at least two approaches are feasible: a rational calculating, planning and marketing view of innovation and a more socio-cultural view. In the first rational view, innovation can be strictly controled, leaving nothing to chance. In that view, the basis of innovation is the monitoring of the market or environment. The belief is that a succesful innovation is market-driven (innovations spurred by market demand). Moreover, innovative processes should be steered by market-pull instead of technology-pull. Both, products and market should be tuned to each other. Here, the opinion is also, that efficiency is the driving force and measure of innovation. In this view, diversification of products by innovations is a logical move in order to get the most rational, efficient and effective solutions on the market. As a consequence of this line of thought, innovation might also be seen as an instrument to control the market by suppressing competitors, to manipulate the client or buyer and/or the own employees.

In the second, relativistic, contextual and social-cultural view of systems, innovations are driven by the self-interest of the people involved. Innovation by diversification is seen as an endeavour and attempt of managers to expand their power. The belief is that people are capable of thinking rationally, but they are doing so from a social position of power, pride and/or self-interest. Innovation is seen as an instrument to manipulate or deceive the market. Integration of activities in the own organisation is also seen as possible. But that is only the case, if the employees are kept faithful by control or other measures, or if the loss of stealing or laziness does not exceed the costs of external buying (out contracting) of services or products. Within this view innovation can be successfully driven by both market-pull (as in the USA) or technology-pull (as in Germany). In any case, in order to innovate succesfully it is important to built, develop and integrate core competencies of the employees with the own, available technologies.

1.5 Short and long term innovations

The process and system approaches can be viewed as the two extremes of a time scale, with differences in assumptions about the possibilities to steer events in some desired directions. At the farthest end of the time scale we are at the mercy of events, afloat in a sea of uncertainty as in Darwinistic selective evolutionary processes. But at the shortest end of the same time scale, we can exploit our capacity to think ahead and instruct events according to our own will and insight, like in Lamarckian evolutionary systems. The psychological and sociological views do occupy in-between positions on the time scale, with at the far end the sociological and at the short end the psychological position. If we want to study innovations, we should take into account these four perspectives of the time scale: from the shortest Lamarckian, over the short psychological towards the long sociological and the longest Darwinistic scale of time.












time scale:    very short



very long

Table 1

And as in natural environments we should study innovations not only as purely competitive systems and processes but also within the context of co-evolving wholes, within complete eco-systems of art, technology and science. But in the end we should not only study the mechanisms (the causes and effects of innovations) exclusively in an analytical manner. We should also help to develop and deliver tools enabling all the people involved in design in order to create, invent, anticipate, decide and implement innovations better within the prevailing social-cultural context and society at large. But to realize all those far reaching goals and tasks, we should start with some modest exploratory case studies as empiral bases for further research and development.

2. Case study

In order to get reliable knowledge, insight and theories for prediction and control the processes of innovation in design offices, we should first carry out case studies of those activities. The selection of the case study reported here is based on the research agenda of my department. It is about urban identity and density and multiple land and building use. Underlying these subjects is sustainability, as it is the overall objective of our university (sustainable technology) and faculty (sustainable architecture, building and planning). The case study is about a new concept of (light weight) roof-top building extension. Up till now this is done in the Netherlands by adding a similar floor, instead of creating (together with an increase of density) something quite different in quality, identity and multiple spatial use. The case study might be conceived as the empirical basis of investigation of architectural innovation as an evolutionary process. It has also the particularity that the architect involved (Eric Vreedenburgh) has for years been collaborating with a computer scientist/artist (Remko Scha). Unlike many architects now publicizing their use of computers in the design process, he is not so much interested in the final product looking like something produced with the assistance of computers. His interest goes much more towards the constant renewal of the design process with the use of the computer as a rapid fire instrument of variety.

2.1 Generative grammar in architectural innovation

The case study demonstrate among others the possibilities of application of generative grammars of architectural forms in a real world context. As is already stated in general in the beginning, the Chomskyan concept of ‘generative’ is about the ability of (in our case) an architect, to generate an infinite number of complex and new, innovative architectural forms based on a finite set of designing rules. Combined with selective retention mechanisms, these generative systems will be transformed in a ‘genetic’ and Darwinian system of architectural evolution. If on the contrary the generation of variety is restricted to the very beginning of the design process, the more common Lamarckian evolutionary system of incremental improvement is practiced.

But in the case of the architectural creative expressions exposed here, there is a generative difference with the linguistical situation. The architect in the case study is stating the rules himself, while a subject uttering the sentences of language uses rules evolved collectively by a linguistic community. The individual architect here is at the same time the grammarian, the linguist and the talking subject. His approach is at the same time evolutionary in various senses. One of them is that he uses the variety producing program ‘Artificial’ of the artist/computer scientist Remko Scha to display a great number of successive generations of his design based on the rules he states. More over, not only the designs evolve, but also the rules. Designing is playing and changing the rules is an intrinsic part of the game. The changes are complex and not only combinatorial. One element of this generative game is using existing materials and artefacts to another purpose than the one they they are marketed for, sometimes building elements from catalogs, sometimes elements taken from previous designs but used in a lopsided way. In fact, this is the objet trouvé technique used by Duchamp, but applied in a real world architectural context, in the tradition of Charles and Ray Eames. Another evolutionary aspect of the design is the way in which the chances, brought by the inhabitants of the design are part of the design game. Users will adopt some of his design ideas and abandon some others. This decay and transformation of his design ideas he accepts as a consequence of his approach. He uses this as a feedback for changing his initial rules. He is also engaged in an urban game with his small, local interventions (called ‘pin-prick urban designs’). The aim is to bring about possitive feedback loops of new developments, in order to contribute in the revitalisation of old urban tissues. Instead of either spending large repair costs or demolition and new development, with his roof-top buildings he offers a full-fledged alternative of re-differentiation of the building supply and demand situation of the particular site involved.

2.2 The history of anything new

Ideas about industrialized building and the like do not exist in splendid isolation from previous thoughts. New is nearly always relatively new, incrementally applied and adapted within other situations or contexts and/or integrated within new combinations of elements. The roof-top building as a meme is such an example of a relatively new idea. It has it roots in the roof terrace buildings of antiquity. But even in the modernist times of the thirties, Le Corbusier was still introducing again a new version of that old idea in the new shape of his time: the passenger boat deck, which he translated in an accessible and usable roof-top cover on his buildings. The relative novelty of the actual roof-top building type is its light weight prefab construction, its application on existing buildings, together with all the other mentioned qualities. Even absolute, first time ever originality deserves some familiarity in order to get identified as something fundamental new. Distinguishing between what is absolute original and what not is difficult and in fact not so interesting compared with the innovative question about how you get the expression or invention implemented in practice. Originality alone is not sufficient to convey value, the original idea should be applied. The novel value of expressions or inventions are in most cases relatively small, they are litle differences between a sea of already known features. What somebody observed as new somewhere will be applied in a quite different way elsewhere and often by someone else.

2.3 Surfing the waves of concurrency

A project is the result of a combination of events and that determines the success of the project. Events are determined by circumstances in time and location. Application failures in the past might be succesful in other circumstances. The decay and need to renovate housing blocks of the fifties and sixties for instance, is only now opportune to react upon. But for a timely reaction the mind of the designer must be receptive to exterior signs. To receive and tranform information is often as creative an act as generating it. The value of what is announced somewhere depends entirely on the extent to which each individual receiver has the receptors. Shared terminology and language, the same interest and attention are all necessary to render what received meaningful. To grasp the possibilities of a situation is crucial. Understanding for instance, the real but hidden needs of the client like in the Harbour View project and next, the meaning of that project as a start for a whole series of more or less similar projects elsewhere in the Netherlands.

3. Memetics and specifics of the case study

This case study is performed to investigate the related activities of expressions, inventions and innovations within the ‘real life’ setting of an architectural office. It does so by applying the concept of MEMES as something like design ideas, concepts, beliefs, and/or behaviours or procedures. These memorable units are stored in brains, evolve in brains, are passing from brain to brain and are externally stored in pictures, plans, photographs, movies and so on (see among the many early writers about memes: Cloak, the pioneer[7]; Dawkins, the spiritual father[3]: James, the historian and importer to architecture [8]; Delius, the theoretician of culture [9]; Dennett, the philosopher of the mind [10]; Csikszentmihalyi, the psychologist of creativity [11]. A closely related memetic study in architectural design was reported in the previous ‘Generative Art’ conference [4] That study was aimed at the identification and categorisation of memes, eventually encountered by architectural students in their projects.The design conception in this case is about the new interpretation of the roof-top building type within the present Dutch situation. The family tree of descent will be discussed together with the fields of application and the sorts of creative expressions and technical inventions implemented in functional, technical, social and formal innovations. This has an impact on both processes and products. Process innovations as they are embedded in activities and product innovations as they are tied up in building materials and elements.

3.1 Roof-top building type as a meme

Around the roof-top building type, a whole complex of memes has evolved: a so called memeplex. For the A meme is a package of information created, replicated and transformed in the minds of people. In our case study that boils down to everyone involved in the creation and realisation of the roof-top building projects. People for instance minding about light weight prefabricated designing and building, or about costs or densities or renewed identities. These memes are internally stored in the memories of people and/or externally stored in computers, on building plans and photographs, on texts and diagrams and many other types of representations. Because of this, a meme is much more than an idea, it might be an image, a song or a procedure about how to imagine, design or  built things such as roof-top buildings. Memes are self-replicating patterns of information which propagate themselves across the ecologies of the minds, here the whole community of people involved in roof-top building projects. That is in the first place the micro community of all the staff members of the architectural office Archipel Ontwerpers, but also of the competitive design offices stepping in the same niche market. On a broader scale the Dutch associations ‘Building with Steel’, ‘Building Research’, ‘TNO-Bouw’ and Corus have studied and published their results about the possibilities of roof-top buildings and taking the designs of Archipel Ontwerpers as their examples [12]. In the same vein, the central government and the large Dutch housing corporations have stated their policies on the subject and the money made available to stimulate the realisation of the objectives involved in the next few years. All the people in these organisations are busy to self-reproduce memes and complexes of memes about roof-top buildings. These memes interact with their social surroundings and adapt to them, they mutate in minds and they persist in publications. Like any other life-form the roof-top memes evolve to fill the fruitful, promising spaces of their local social and political environments, which are in this case the surrounding belief systems and cultures of their hosts, the people involved in the propagation of roof-top building projects. The roof-top building meme(lexe)s evolve constantly in forms more perfectly adapted to their environment. They are relentless expansionist, always seeking new opportunities. The more universally resonant a meme is in the shape of an idea, an image or a recipe (design or building procedure), the more minds it will reach and occupy. The roof-top building type is about a whole memeplex associated with industrial building. The industrialized building of modernity is also a memeplex, but one of the recent past. The industrialized building conception of our time (as it is also applied in the roof-top buildings) is a mutation or child meme of that old one, adapted to our new information based culture of lean- and just-in-time-production techniques. In this respect, memes behave like old secrets which have the desire to be told within new circumstances.

3.2 The family tree of the roof-top building type

The tree of descent of the roof-top building in our case study was started with a request in 1995 by a client for a detached roof expansion. The following is a shortened version of the flow of ideas involved in the interaction of client and architect.

The client wanted a semi-detached extention with roofing tiles and it should be built on two small former store houses for freezing fishery products. In talking to the client, Eric Vreedenburgh, the architect-designer in our case study became aware that the client had lived on the West coast of the USA. He asked him to travel in his imagination along the coast and let him remember how relaxed everybody lived there in modern steel framed little houses with a view on the sea. The would-be client had a nice little steel lamp on his desk and an unvarnished surf board on the wall. Eric Vreedenburgh associated and compared those objects with what he could see from the desk: storage buildings with cooling installations on top. He said to the would-be client that if he got the commission, he would give the design (with a wink to Magritte) an impression of a coincidental meeting of a steel lamp and an unvarnished surf board. Two ordinary objects together could result in something beautiful like the harbour he was viewing at from the desk: ordinary buildings surrounding the water, but together they got their special character like New York. In parting, the client said that he might be persuaded and that was the start. The first design sketches were inmediately to the point and are realized afterwards without much alterations. What the client got was a penthouse of steel and some wood inside on top of his former freeze-store-houses with a beautiful view over the fishery harbour of the seaside town Scheveningen: an exquisite place to  built a new type of roof-top building with qualitatively new features. The penthouse, now called Harbour View,  got new, hardly applied functional creative expressions and technical inventions. Because Harbour View is now realised, it represents a first real successful innovation. Building on this innovation, four other roof-top buildings are now proposed and in development by Eric Vreedenburgh on adjoining fronts of the same fishery harbour. Because all this was brought about by Harbour View we can interpret it even as a succesfully micro urban design project.

3.3 Fields of application

The projects around the harbour of Scheveningen are an example of how roof-top solutions can be applied to an urban development environment dealing with industrial inheritance: conservation and adaptation of the obsolete buildings below to accommodate new activities and replacement of the deep freeze and smoke installations on top with look-alike steel framed roof-top buildings, as a reminder to the industrial past.

In the same period the roof-top building idea (memeplex) was applied in the historical inner city environment of Amsterdam. Because of the unity of the monumental merchant houses, the roof-top solution is made as much unconspicuous as possible.

In IJburg, the last large extension of Amsterdam and now under construction on a part of a former inner sea, the roof-top building idea is used to complement a new building complex as if it were an existing structure. This will ensure the variety of building types and all the different activities involved.

In Rotterdam two demonstration projects are underway, based on existing housing blocks with flat roofs. This is a very typical situation in the Netherlands, where a vast amount of flat roofed housing blocks were built in the fifties and sixties of the last century. Here, renewal is pending, either by demolition and redevelopment or spending large repair costs with or without re-differentiation of building types and corresponding activities. Within a few years much more than ten billion guilders will be spent by the central government and housing corporations to solve this housing blocks problem. The two projects are on the two extremes of a spectrum: one with a roof landscape of five basic penthouses and the other one with a very complex and expressive villa. The penthouses will be built in a steel frame building system and the villa in a space frame system. In both the industrialized way of building should be intimately connected to a personalized living environment. Production in response to personal demand instead of the anonymous monoculture of mass production, represented by the housing blocks underneath.

To produce this on demand production system of unique buildings the variety producing program ‘Artificial’ will be used and even adapted for this special occasion. Because ‘Artificial’ was developed originally as an art program to make a statement, an evaluation function was deliberately left out, but for this application it will eventually be implemented.

3.4 New expressions and inventions

What sorts of creative expressions and technical inventions are now incorporated in the various fields of application of the roof-top building type? If we look at the stated explanations and comments of the architect about his roof-top buildings, we find claims aiming for functional, technical, social and formal innovations and in both their process and products disguises. Process innovations as the are embedded in activities and product innovations as they are absorbed in building materials and elements. Because some of the claims are already implemented in the finished penthouse, some of the innovations are already realized, at least to a certain degree.




New ways of:


New types of:


spatial organisation

spatial configuration



building assemblies






identity construction

Table 2

 Innovations of the functional process are intended or implemented about the new ways of client-designer communications. Next to it, there are plans for the introduction of new, evolving, self changeable rules of playing for living, working and recreation. Also new ways of spatial organisation are embedded in the floor plans: they should enhance individual spatial selection and use and be flexibel to changing uses and users over the years. A relatively new feature is the posibility to enter the the top-location buildings in the centre from above or below, leaving the façades uninterrupted and free of being exposed from people looking in. Because the buildings occupy the roof-tops there are less problems with privacy and better conditions for views to the outside.

Innovations of the functional product are expected by this type of top-roof building as a symbiotic top part of the main building, eventually equiped with plug-in units and/or recombinatorial spatial units.


Innovations of the technical process are anticipated in new production techniques and tools for one-off industrial production as it is implied in the design of the top-roof buildings. The design of the building elements is uncoupled to get as much as posible project-non specific and independent exchangeable units. Attention is paid to get maintainable and fault tolerant building elements. Size and weight are choosen for easy transportation and the materials and construction selected for fast and dry assembly and de-assembly. With all these features the deployment of a general contractor is made superfluous.

Innovations of the technical product are realized and foreseen with new applications or combinations of existing building elements and materials. For instance the application of a steel frame with an overhanging shell roof of an already realized former project. Or the use of a steel frame with special wooden infill materials. But if the product is like a steelframe, their meanings might still be about something else: for instance about production techniques, esthetics, life styles and the like. In general the use of frame construction and in-fill elements are designed with sustainable characteristics in mind: durable, energy efficient, fast transportable and erectable, dry demountable, uncoupled, maintainable, free exchangeable and with a project-nonspecific build-up. Together, they make up for all the properties to avoid the general contractor.


Innovations of the social process are aimed at with new cultural ways of differentiation between living, working and recreation. With the roof-top buildings, ‘pin-prick’ urban design is also possible to re-vitalize and gentrify the urban environment.

Innovations of the social product is realizeable with the building of those pin-prick top-roof penthouses and top located urban villas.


Innovations of the formal process is intended to generate designs with the variety producing (and eventually evaluation) program, called ‘Artificial’.

Innovations of the formal product is aimed at with a new, mixed type of identity, based on the logic of the building systems pattern on site, combined with the local identity of the surrounding site and the global identity of industrial products: their trademark and/or model-type identity.

3.5 Incremental innovations

In the case study, the architect involved mentioned that potential innovations are developed in a piecemeal fashion. What he put to the question resembles the well known creative technique of association checklists. In psychological association theories, reasoning and creativity are seen as a process of connecting memes in closely knitted memeplexes. These conveyors of meaning in our mind are capturing aspects of the world to adapt them for other purposes and eventually pass them on to designers and other users. It seems that artistic expressions and technical inventions are depending for a large extend on these associations for their transformation from old to new. In the case study this was brought up by comments about the novelty produced as a result of an unusual, unexpected and/or remotely connected way of ‘SCAMPER’ing them (Alex Osborne’s associative creativity technique of ‘Substitute’, ‘Combine’, ‘Adapt’, ‘Modify’, ‘Put to other uses’, ‘Eliminate’ and ‘Rearrange’) [13]. If we take the boost word ‘combine’ as an example, designers might combine the adopted meme(s) with an other meme(s) as they might be related to other functions or other materials or building elements. This seems the most sensible strategy to follow by architects anyway. For novel expressions or inventions, you need new, unexpected elements, but because of the costs and other efforts involved, you should use available technology to the utmost. This boils down to the selection of available parts of the vocabulary of different producers of building elements, making adjustments in both the vocabulary of elements or assemblages and the grammar of connections to combine them within a new, unusual whole. As a necessary basis for the creation, discovery, identification and formulation of the needed operators, the associative activities depend on the availability and applicability of the knowledge of the architect. A knowledge about open, flexible product designs, industrial production techniques, light weight steel frame constructions and urban density consequences.

4. Framework

A framework is needed to observe and collect information in a purposeful way about new expressions, inventions and innovations in the architectural design processes of the case study. This could be based on a previous study of Yu-Tung Liu [14]. His framework attempted to describe creative behavior. To that end he combined two previous frameworks from Simon et al. [15] and Csikszentmihalyi [16]. Simon et al. made a framework about creativity, but restricted themselves to the individual designer (Figure 1).


 Figure 1  Simon’s e.a. dynamic framework of creativity.


Csikszentmihalyi on the other hand has paid attention in his framework to creativity as a social-cultural phenomenon (Figure 2 ).



Figure 2  Csiksentmihalyi’s dynamic framework of personal and social-cultural creativity.





Figure 3   Yu-Tung Liu’s dynamic framework of personal and social-cultural creativity.


Yu-Tung Liu has integrated both views in one extended framework (see

Figure 3).

In order to distinguish between the two main evolutionary processes eventually at work in creative behavior, the framework is here once again extended with Darwinian and Lamarckian behavioral categories of designing (

Figure 3) .


In the following paragraphs, all the questions thrown up by the behavioral categories of the framework will be answered with what was found in the case study. Within the flow of the framework the role of memes is investigated: their individual as well as collective transmission, consumption and creative transformation within de design processes explored in the case study.




Figure 4
Dynamic framework of personal and social-cultural creativity within a Darwinian snd Lamarckian evolutionary system of architectural designing showing the flow and transformation of novel memes.

4.1 Identification of problems: is a new, own field of problems identified?

In the case study, there is a whole complex of problems distinguished:

- about residential culture (as a reaction against the stripped standard Dutch housing system, now realized everywhere on meadows as residential areas)

- building techniques (single unit industrialized, flexible, durable and sustainable production systems, that does not bring about monocultures)

- urban renovation, density and differentiation (another approach in urban design with pin-prick, density and differentiation enlarging projects)

- how does one get along with history and context (in industrial areas, historically important inner city sites, obsolate housing blocks and new building developmens).

With the new conception and elaboration of the roof-top type of building, this whole field of problems is dealt with, within the various contexts of industrial heritage (Scheveningen), historical inner city (Amsterdam), a residential area on new land (IJburg) and mass produced housing blocks from the fifties and sixties (Rotterdam). See for a closer look on the projects involved, the two paragraphs about ‘The family tree of the roof-top building type’ and the ‘Fields of application’.

4.2 Production of alternatives: is the design effort directed to a variety of solutions?

The search for variants at the design office is at least partly done deliberately in some occasions. Either by applying the variation producing program ‘Artificial’ or in cases where for instant the industrial production of series is involved. This search for variants is almost a starting point of the design office. This is irrespective of the scale of the task: from urban design, architecture to the design of furniture. The penthouse was a singular piece of work, but was also seen from the beginning as a potential first product of a series. Five years later, there was a possibility to realise that potential on another store house on the harbour and the architect of our case study took immediately this opportunity to design a new alternative (basic, different variant). From there on, he got another opportunity to design an alternative and then an assignment of the Dutch Steel Building Institute to design a whole series of examplary alternatives. That again gave rise to the roof-top projects on obsolete housing blocks in Rotterdam. Besides the first design skeches, there is also considerable design work done with several cardboard and CAD models, again resulting and contributing to the production of variants.

Alternatives and variants come often into being by chance and luck, but only if there is a prepared mind to identify them and then. Designing takes place within the field of tension of necessity, chance and free will. Necessity constrains the solution space, chance uncovers new possibilities and free will facilitates decisions between possibilities. A combination of circumstances might bring about new variants or even fundamental new alternatives. Coincidences take place on many occasions. This begins already right at the start of a commission. At the harbour site in Scheveningen for instance, the responsible urban designer agrees with the architect on the desirable transformation of the site, and this communis opinio leads to new assignments for the architect. On another site in the same city of The Hague (part of which is Scheveningen), with another responsible urban designer with other insights and ideas, no commission was possible. Other chance hits are introduced by free association in the design process: the mentioned way of ‘SCAMPER’ing (‘Substitute’, ‘Combine’, ‘Adapt’, ‘Modify’, ‘Put to other uses’, ‘Eliminate’ and ‘Rearrange’) building elements and/or spatial arrangements in order to get some new expressions or inventions. Problems are not deliberately looked for or deduced from first principles. They come just along by chance and are identified from the personal background of experiences of what is seen as important: open, flexible situations for the appropriate application of product designs, industrial production techniques, light weight steel frame constructions and urban density measures.

For Eric Vreedenburgh chance, luck and visual imagination are interlocked. The problems are transformed into solutions or parts of solutions and imagined as stationary or moving pictures. Thereafter, these images are tested and adapted in a puzzlemaking way. During this activity the designer of our case study is dreaming away and as a result, is getting new ideas by chance from the subconscious. Getting ideas happen everywhere, even during sleep. During his dreams he is walking through his designs. Most ideas are not immediately applicable to the problem at hand, but they will still come back in other projects, often mixed with other ideas. In this respect, the designer of our case study is carrying on a whole library of images and solutions in his head. This include also examples (precedents) from other architects and the past. Depending on the context, some imagined ideas might grow and others are forced to wait.


4.3 Revision of a solution: is the design effort directed to one solution?

At least some of the design work is done with only one solution as a starting point for more detailed elaboration instead of diversification of solutions. The penthouse for instance, was designed as one solution, without alternatives being developed or immediately presented to the client. But still there was an awareness of the potential of the example and the possibilities to expand its application with alternatives on and off the harbour site. This include the symbiotic relationships between the light weight roof-top building and the brick substructure underneath. The first as living and office environment, attracting commercial functions in the substructure beneath and as a consequence, transforming the old, existing building. Moreover, he design effort after the approval by the client and the local authorities is also directed to one solution.

When designing is aimed at one solution only, this might be compared to the selection of one point in a fitness landscape when seeking an optimum: without knowing if you are either stuck in a local suboptimal hill or on the right slope of the highest mountain of best solutions. The elaboration of that one chosen solution might be compared with the erection of a tower, an artificial hill or pyramid, to revaluate the given fitness landscape. This corresponds with what might be observed in processes of cultural evolution. Something is judged as unsufficient and is improved accordingly. For instance, a stair is experienced as too short and is improved by lengthening it. This Lamarckian principle is based on the so called depth-first strategy. You choose one seemingly best solution as soon as possible and then test and improve it several times. A person trying to design in a rational way with necessities as a basis of decisions is behaving in a Lamarckian evolutionary fashion. For instance, the definition of the design space in order to explore it systematically, is such a rational strategy.

According to the architect of the case study, he goes to and fro between hitting upon an idea and methodological investigation of that idea. However, you do not get ideas from systematic thinking. Fantasy delivers the idea by chance, thinking give the reflection and is based on reasoning with design as well as with context and performance variables. Methods are used to explore the fantasy, the imagination is used to make up adequate methods. In the same vein, Eric Vreedenburgh combined research assignments at the University of Technology in Delft with his design practice. For him, both fantasy and methods are needed and cannot exist without each other. Visual fantasy is like storytelling, but instead of hearing the words, you are seeing pictures as stationary or moving images. After imagining, the architect tests these pictures on their applicability. And like puzzlemaking he -together with his whole office-, tries to adapt these preliminary images to meet the regulations and requirements, the needed dimensions, the applicable techniques, the available budgets, and so on.

4.4 Individual  testing of solutions: does testing take place in the office?

Eric Vreedenburgh is the only one in the office still using hand drawn design sketches. As soon as these sketches enter the computer, tests are conducted by everyone in the office and also together with the client and the local authorities. The tests performed are about mundane affairs like the consistency of the applied building system, money involved, planning, the feasibility according to the market and politics. Ideas and concepts out of which designs are born, are not part of that system of testing, because usually nobody has explicit interest in the outcome. The tests within the office are based on collected knowledge and experiences. The largest problems come to the surface when the external advisors are doing their tests without thinking along the unconventional, designerly lines of the architectural office. The general culture there is focussed on safeguarding against any risk possible and avoiding any research at all. The same is true with most general contractors and developers. On the other hand the office has earned several prices in just taking risks and doing research in order to obtain expressive creations and inventive solutions. The motto of the office is: every renewal has its risk, but a culture suppressing people dare to take the risk is really in danger. The tests are done on the basis of the hypothetical fitness landscape as it is reconstructed from reality by the individual designer or group of designers in order to anticipate on the fitness assessments in the real world.


4.5 Social testing of solutions: is the design(er) socially-culturally tested?

Social-cultural tests are performed by entering competitions, by participating in appropriate movements, attending workshops, joining in debates and (last but not least) by realizing the designs in practice. The realization of projects is an indication that they are approved and supported by the clients and the local authorities, in spite of their acknowledgement about the expensive costs involved in the proposed complex quality projects. By getting awards and invitations to participate in publications, exhibitions, workshops and the like, the success of the tests might be measured. These are thus tests within the socially constructed reality.

Sustainability represents one framework of tests to evaluate the social value of the projects. Transformation has to do with the functional and technical extension of the durability of the building, like in the same vein the demountable detailing might be aimed at the recycling of materials and products. The social value might also be measured by the attraction of the projects bring about to new urban activities on the site involved and its role in the revitalisation of the local urban identity.

4.6 Storage of solutions: are socially accepted documentations accumulated?

Socially approved and stored files or documenatations are available about existing solutions, ideas, knowledge, information and/or data.

• With regard to solutions: all sorts of penthouses are published as precedents in a variety of books and journals. Eric Vreedenburgh has contributed to several of those publications. For instance in a Dutch book about ‘building on top locations’, a compact reproduction of a research study about ‘the application of steel in urban habitat’ of several Dutch firms and research institutes. The spatial contribution by Eric Vreedenburgh was in that case about the expressive possibilities of large spans and cantilevers in steel frame top-roof buildings.

• With respect to ideas: there is already a plethora of information folders about the possibilities of renovation and expansion (and subsequent social and functional redifferentiation) of aproximately fifty years old housing blocks. Ideas abound on the addition of elevators and roof-top extensions and the reorganisation of floor plans in order to get more flexibility and variability of production and use. Or ideas about the contemporary interpretation of the arrangement,  about contemporary finishing and appearance. Eric Vreedenburgh has contributed to the development and dissemination of those ideas. He made suggestions and plans about the possibilities of the obvious use of light weight building materials like wood and steel, and the application of prefab elements to realize those ideas.

• In relation with knowledge, books are available like the already mentioned ‘building on top locations’ or the publication ‘Optoppen’ of the steering group of experimental housing. Also available is the ‘manual with checklist for plan development’ of the Dutch building research foundation SBR, where you find all the necessary knowledge to design and build roof-top buildings. Another publication is about ‘vitality by pluriformity’ of the city of Rotterdam with an explicit reference to the case study work of Eric Vreedenburgh. A more general sign of social acceptance can be found in newspapers and journals reporting about the projects of the case study and inquiries from Sweden, Italy and the USA.

• In connection with information and data available is the Dutch law about ‘urban renewal’ of the ministry of housing, planning and environment, with regulations, facilities and an investment budget of four billion Dutch guilders for the next few years. Beside it are the investment plans of the housing corporations of nine to eleven billion guilders, depending of the period of spending of the money and also aimed at the revitalisation, redifferentiation and sustainable development of the aproximately fifty year old housing blocks.

4.7 Retrieval of solutions: is existing documentation available and applicable?

A lot of documentation exists and is also available and applicable. Experiences were obtained with the design and building of the penthouse Harbour View from 1995. And thereafter the four other projects on the harbour site in Scheveningen, one somewhere else in The Hague and two in both Amsterdam and Rotterdam. Recently, some other architectural offices have also acquired expertise with the roof-top building type. Further, data and information is available from the literature about flexibility, industrialized production, light weight construction with wood and steel frames, urban density measures, etc. While looking for information on innovation, it is not sufficient to scan socially accepted documentation. Not previously recorded knowledge should be taken into account, both about what was successful and what failed.

What is socially accepted will reach us by publications, regulations, reports and the like. All this information is filtered and controlled by gate keepers, experts, journalists and other critics guarding what will get into the journals and books and people from local (and other) authorities deciding about permits, permissions and/or subsidies. Several penthouse projects concerning the case study are already gone through these social filters successfully. Others are in preceding phases of development, either accepted by the architect alone, or by the client and/or some of the local authorities as well, but not yet recognized by the profession as a whole or the general public.

However, most of the ideas (or fragments of ideas) about the roof-top buildings do not come (as far as he knows) from journals or books, neither from discussions on and off the office, but mainly from preceding designs back to students times. Associations, metaphors and analogies are playing their roles, as well as important, stimulating predecessors and followers. About influential people: from Le Corbusier to Rem Koolhaas, who was his supervisor. And last but not least the harbour buildings of Rotterdam as a random stacking of volumes, resulting from a very economical logic.

5. Diffusion

A following step of research of architectural innovation should be the study of the diffusion and evolution of the architectural memes involved. In the case study, memes (partial or complete ideas, beliefs, procedures) are evolved (inherited by copying or imitation, varied by mutation and/or recombination and selected by the mind’s already established memeplexes). They are evolving in the minds of everybody involved in the design processes of the case study, in order to develop in new memetic expressions and/or inventions (and if implemented evolving in real world innovations). As fragments or complete memes of new expressions or inventions, they are communicated (copied, imitated, inheritated) from mind to mind in some pattern of spreading (diffusion). The resulting pattern depends from the susceptibility of the minds involved to be entered (invaded, penetrated).

5.1 Architectural diffusion of styles and types

In architecture, new expressions are mainly communicated by style and inventions by type. Style is about meaning, type about structure. Style has many readings, multiple interpretations and strong moral overtones. Type on the other hand is about remedial actions, to bring about some effect(s). For instance a sliding door and a revolving door are typologically different in their handling and effects, but might be designed in the same style, whether  a deconstructivist, postmodern or biomorphic style. The history of architectural studies is nearly always about styles. The study of types is much more recent and restricted. The diffusion of stylistic and typological innovations is quite different. Stylistic innovations diffuse fast and chaotically within a multitude of stylistic trends and movements: popping up for a short time and then either fading away after some months or years or evolving into one or more other stylistic trends or movements. All this happens in spite of an undercurrent of a few, long term, coherent traditions. Typological diffusion follows a much slower pace of adaptation and replacement. For instance, the basic structure of organisation of a basilica survives Romanesque, Gothic, Renaissance or Modernist styles. Inventions are based on new or modified principles, recipes or configurations, bringing about new or adapted and desired effects for using, doing or applying valued things.

5.2 Lineage diffusions of designs and designers

The diffusion of new expressions, inventions and innovations with directed graphs or networks will show us a lineage tree of development. In the case study the lineage development of the roof-top building type as an idea (meme, memome or memeplex) might be conceived and studied as either a tree with a forking branch pattern or a semi-lattice with a reticulated branch structure. In organic evolution we find forking branch patterns: after a splitting of a branch has taken place, a reunion, refusion of joining of divided branches is (after a short hybridization period) impossible to realise. In cultural evolution on the other hand the semi-lattice with the reticulated branch pattern is the most common structure encountered. The nodes in both types of pattern represent the different (sketched or realized) designs involved in the study and the edges the lineages from node to node. What the branch pattern reveal is the development of the expressions, inventions or innovations in time. Here about the development of the roof-top building type, whether as realized and/or as sketched projects. As a consequence of this type of studies, we might get some qualitative insights about the variety already created and identified. But all this remains to be investigated in the future.

5.3 How do memetic innovations diffuse (spread) over minds ?

According to Brodie [17], memes diffuse easier if they are identified in minds as a solution for a ‘crisis’ or a ‘problem’. For instance a solution for the shortage of buildable land in our case of roof-top buildings.

Memes are also valued by minds if they might enhance survival from ‘danger’. This might be translated in our case about the danger of losing old industrial heritage and the possibilities to preserve them with roof-top buildings.

Another encouragement for minds to accept memes is if they suggest ‘opportunities’. For instance in our case a new, improved social, economical and environmental quality and identity of the site as a whole. Or the opportunity to distinguish yourself by owning a penthouse on a housing block.

Because the roof-top memes are relatively new, they will encounter resistance of other memes already infested in minds and by their very nature fit to spread effectively. Such self-perpetuating memes are based on ‘evangelism’ and ‘faith’.

Evangelism (or the intentional spreading of memes) is needed to promote (in our case) the design and construction of roof-top buildings.

In order to promote reliably, faith is needed about the credibility of the own belief system, the own ideas and activities. In our case study for instance, faith about the appropriateness of industrialized building with prefabricated light weight elements, the social impact of the roof-top extentions and so on.

If a meme is associated with a ‘mission’, such as about ‘sustainable building and living’, it has again a better chance to survive. By adding roof-top buildings above existing housing blocks the whole gets a longer life span and that means also a better sustainability rate (another ‘mission’).

What might be propagated is also often formulated in ‘mission’ memes. The existence of associations, corporations, societies, councils or foundations are often based on explicitly stated missions. One of those (Dutch) working groups Eric Vreedenburgh agrees with is IFD, an acronym which stand for Industrialized Flexible Demountable designing and building. The D often stands for Sustainable (in Dutch: Duurzaam). Boosting was the name of another (Dutch) organisation with a mission committed to industrialised building and was also adhered to by Eric Vreedenburgh. As a member of those organisations, he and his memes might have better chances to spread and survive.

Memes ‘that makes sense’ or are ‘familiar’ with other already acquired memes might also have better survival chances in the diffusion process. Rational arguments and explanations might support that sense making and giving information will enhance familiarity. Sense making and familiarity wil be enhanced in organisations such as the mentioned IFD or Boosting.

5.4 How memetic innovations infect (penetrate) in minds

In the same vein, meme infection might be caught by either (1) ‘conditioning’ or ‘repetition’ (you must be exposed several times to a meme), or (2) by by making conflicting memes consistent with the already aquired memes (called ‘cognitive dissonance’) or (3) by sneaking in undesired memes within a set of positive acceptable memes (called ‘Trojan horse’).

In the case of the roof-top building meme, infection might be effective after repetitive exposures to workshop presentations, articles in journals and newspapers, enthusiastic comments from colleagues and so on. Or infection might be conditioned by positive association: new roof-top penthouses in old, obsolete situations with poor people, might rejuvenate the social mix and diversify the demand for schools, shops, restaurants and other facilities.

An example of a self-imposed cognitive dissonance (the creation of a mental high pressure situation and resolving it) is introduced by Eric Vreedenburgh with the application of the generic program ‘Artificial’ in his designs. He is forced to make incompatible forms consistent with plans according to the brief of the project involved.

The Trojan horse way of sneaking in less desired memes in the minds by bundling them with more welcome memes might be realised if we use the mentioned appealing memes of ‘crisis’ , ‘problem’ , ‘mission’ , ‘danger’ and ‘opportunities’. For instance, owners of expensive roof-top penthouses might be better accepted by the other inhabitants, because they assure the survival of the housing blocks as a whole.

5.5 How memetic innovations reproduce (copy, imitate, transform) within minds

Because the roof-top memes are relatively new, they will encounter resistance of other memes already infesting minds and by their very nature fit to spread effectively. These self-perpetuating memes are based on ‘tradition and ‘skepticism

Tradition and skepticism are needed for a faithful reproduction of memes but they are also building resistance against new memes and should then be attacked,

Evangelism and faith should be exploited for spreading memes.

Tradition is a strong force to continue past beliefs and activities. Why should you apply roof-top buildings with all the risks that inexperience bring along? But on the other hand, to design and built roof-top buildings without too much risk, Eric Vreedenburgh himself refers to an tradition of industrialized design and building.

Scepticism questions the ingenuity of new ideas and beliefs and results in strong resistant against anything new, killing any sparking of creativity. But there is an effective way to bypass scepticism: get the trust of the skepticist. It makes him susceptible again for the acceptance of new memes.


On the basis of this single explorative study, we might preliminarily conclude that architecture is submitted to evolutionary processes and that it might results in innovations. Architectural evolution might be about both the processes and the results of designing. As a process of architectural designing, the Lamarckian way of evolutionary development seems to be the most common one applied in architectural practice. But the Darwinistic approach is still available as an alternative if the Lamarckian approach goes wrong (or in the absence of inspiration). Most design processes are mixtures of these two types of Lamarckian and Darwinian evolutionary principles. CAD and generic software (like the applied program ‘Artificial’) might be used to produce blind variation within the broader selective inheritance system of designing. A distinction is made between expression, invention and innovation. Artistic work can be expressed, technical accomplisments invented. Both will be called innovation, after succesful implementation in practice. A case study seems appropriate to study in an exploratory way the evolution of both, design processes and design objects. Because the objective of the enquiry was to collect qualitative information about the presence or absence of evolutionary and innovative processes in architectural design and designing, there was no need to look for an representative sample of case studies and/or architects. The only requirement was to identify a case where the chances were maximalized that all the distinguished processes of evolution and innovation might be probably present. The framework used to structure the observations in the case study seems suitable to classify the distinguished evolutionary processes of architectural design without loosing important information. The information content flowing through the framework is analysed as memes (packages of ideas, beliefs, behaviours, procedures). in order to get an impression of how they infect or penetrate in the minds of everybody involved in the design case, how they might diffuse or spread over minds and how they are copied, imitated and transformed within the individual minds infected.


This explorative study could not have been carried out without all the information supplied by Eric Vreedenburgh (case study) and Remko Scha (author of ‘Artificial’). Many thanks to their willingness to cooperate generously.



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