The main purpose of the explorative model is to discoverother realities by speculation. This speculative processinvolves systematically varying the parameters usedin the descriptive model in order to identify thosealternatives that are logically possible. In the contextof architecture, models produced as part of the design-development process can be considered explorativemodels. Explorative models, along with drawings, canbe used as a method of refining judgements, makingdecisions or conveying information – factors that areat the very core of architectural design. Explorativemodels, by their very nature, are used to try out andtest different ideas at different degrees of scrutiny, andconsequently they are used at various stages during thedesign process. However, they are typically employedthroughout the early stages of design development, whenthe designer’s ideas are at their most novel, and thensubsequently developed prior to specific properties ofthe design being investigated through the application ofother types of models, as described earlier in this section.The key characteristic of an explorative model is that itis concerned with testing out new ideas. These may notbe exclusively structural concepts, but may often involveexploring different shapes, geometries or constructionmethods that will emerge from experimenting with formand material in different ways.

Explorative models may cover a vast spectrum of methodsfor representing ideas. From the highly detailed to thepurely diagrammatic, they can communicate the subtlecharacteristics of a design’s underlying principle – or evenact as a symbolic object for the project 

In direct contrast to the descriptive model describedearlier, the design development model affords quickmodification – or even radical change – in order to testideas, rather than preciousness. That is not to say thatthere can be no refinement in such models. However,rather than the focus of a design development modelbeing on the quality of the finish it is on the refiningof the emergent design concept. Consequently, manyexplorative models in architecture are quickly produced,and may appear unfinished since they function asthree-dimensional sketches to help develop the design.Such models, however crudely built, give expressionto ideas, and help a designer explore what is possibleand communicate new design notions. As has alreadybeen illustrated within this book so far, the designdevelopment process encompasses a range of modelsfrom basic conceptual forms to detailed componentinquiries. Such models are typically produced rapidly andinventively, using a variety of mixed media to symbolize,for example, relationships between the components of abuilding concept or its response to its context.

Designers who prefer to develop new spatial ideasand formal inquiries directly in three dimensions useexplorative models as an initial design tool. Whilstcommonly perceived as a personal and embryonic three-dimensional sketch, the spontaneity and immediacy ofsuch models is of particular significance since it enablesthem to be a very flexible medium. Being quicklyproduced from easily worked materials, it is their singularfocus on contrast in shape, size and colour that facilitatesrapid change and development. In addition, whereas thepresentation model seeks to provide a holistic view of thefinished architecture, the design development model maybe produced in order to explore particular componentsof the design. As the form of a new architecture emerges,a whole series may be constructed of more specializedmodels that respond to questions arising from the initialevolution of that architectural form. These are studymodels, i.e. complete or part models specifically builtto address certain issues. By working directly in space,albeit at small scale, concepts are formed and refined as aresult of their exploration in three dimensions – a processin which options remain open in design routes, whichmight not be readily apparent to the designer using two-dimensional drawing methods alone.

Whilst there are many different types of architecturalmodel, the use of the explorative model can be aparticularly important part of the design process.Although the majority of architectural practicescommission or build the more familiar descriptiveor presentation model – immaculately crafted andexpensively built – for client and/or public consumption,many still use explorative models as tools for engagingwith the spatial problems and other aspects of adesign. Perhaps, however, we are currently witnessinga renaissance, in which the explorative model is usedand shared with client and public groups. Once thehidden tool of the architectural designer, these modelsare increasingly being applied as discursive vehicles incommunication with those outside of the immediatedesign team – an attitude expressed by Rem Koolhaas,who refers to this process as showing clients creativethinking produced in its raw form.