Parametrics in Urban Design A Bridge to Cross the Gap Between Urban Designer and Urban Dweller? Nicolai Steinø Dept. of Architecture, Design and Media Technology Aalborg University steino@create.aau.dk Esben Obeling Independent researcher esbenobeling@gmail.com Abstract. On the basis of an initial test case, this paper presents some first perspectives for a parametric ap- proach to urban space design as a communication tool in urban design processes. Three aspects of this work will be addressed. First, the basic notion of parametric urban design is explained as well as why it is potentially powerful as a communication tool and democratizing agent. Second, an example of its implementation by means of CityEngine is given and discussed with re- spect to it pros and cons. And finally, the potential im- plications of this approach are touched as an outline for further research. Keywords: parametric design; communicative urban design; CityEngine I. INTRODUCTION The design of urban space has always been contest- ed. Whether imposed by autocratic rulers, emerged as a result of market forces, or implemented as a result of democratic planning processes, urban space design shapes the lives of urban dwellers. Yet rarely does the average urban dweller have any real influence on the process of urban space design. This is due to a number of factors. Lots of money, influence and power is vested in the design of urban space. In this sense, urban planning is inherently political, as numerous theorists have pointed out. i, ii, iii In other words, the design of urban space hap- pens in a space of power. And this is something which traditionally the average urban dweller does not have. Urban designers (architects and planners) communi- cate about urban space design in a professional lan- guage and through graphics which are not necessarily intelligible to laypersons. Additionally, as we shall explain below, there is an inverse relationship between understanding and influence for the ordinary man, as understanding requires detailing which, in turn, tradi- tionally is only feasible once central design decisions have been made. Finally, communicative processes take time. If communicative urban design processes should be mea- ningful, they must allow time for presentation, discus- sion, and revision of design scenarios. And often this is not feasible within the given time and resource limits. iv, v, vi And again, the layperson, whether she is a resident, a local business person, or a NGO representative, is left with little influence, when it comes to the design of urban space. With the advent of parametric design tools however, this needs no longer be the case. Rather than making one-off designs which need to be redesigned from the ground up in case of changes, parametric design tools make it possible keep the design open while at the same time allowing for a level of detailing which is high enough to facilitate an understanding of the generic qualities of proposed designs. vii As such, they potentially offer themselves as com- munication tools. This may happen in the format of public urban design workshops such as design char- rettes, future workshops, urban forums and the like, viii, ix, x, xi as well as through online interaction and communi- cation (though the latter is not discussed in the context of this paper). II. PARAMETRIC URBAN DESIGN AS A DEMOCRATIZING AGENT In any collaborative urban design process, some as- pects – or parameters – are more likely to be relevant to examine and discuss than others. But they are not likely to be the same for different cases of urban design. In one case, density and building style may be topical, while in another case, environmental issues or the dis- tribution of different building programs may be relevant issues to analyze and negotiate. While communicative urban design has been around in Western Europe and USA for decades, xii a number of dilemmas exist for communicative urban design. First, while it is a powerful, if not essential, means to success- ful urban development, it can also be resource and time consuming. Second, as it involves both professional designers / architects and planners, as well as laypeople, differences in thinking and language between profes- sionals and laypeople represent a potential communica- tion barrier. xiii Last, there are opposites of influence of understand- ing. In the early phases of the design process, the design is still open but the level of detailing is typically low. Therefore, the implications of the design may be diffi- cult to understand for laypeople. And ironically, as the level of detailing increases, making it easier to under- stand the design, many design decisions have been made which can no longer be changed without consi-