If we are to deﬁne the descriptive model in generalterms, then its purpose is to assist the understandingof reality by establishing the emergence of a particularphenomenon and describing relationships betweenrelevant factors. Put more succinctly, its primaryintention is explanatory. As has been mentioned earlier,any description of reality brings with it many issuesregarding accuracy. The most familiar type of descriptivemodel in architecture is, perhaps, the ‘presentationmodel’. The presentation or descriptive model typicallyillustrates the complete and fully detailed arrangementof an architectural solution, often within the contextof its immediate surroundings. A key characteristicof the presentation model is that it usually signiﬁesthe end of a critical stage – and even, sometimes, theculmination – of the design process. Distinguishablefrom the exploratory architectural model used for designdevelopment, this application of a model incorporatesminiature components of the architecture representedin detail and as a complete, ﬁnished entity. A signiﬁcantdifference between the decorative representation of abuilding and the representation of architecture needsto be made at this point. Descriptive models typicallymake the architecture coherent and easy to understand;for example, such a model may feature cladding panelsor other such construction and structural componentsthat are arranged to clearly indicate how the ﬁnishedbuilding is intended to look. By contrast, if we refer tothe example of a doll’s house, this too is a model of acomplete building but it uses motifs and symbols ratherthan components (such as brickwork printed on paperand glued onto wall elevations). In this sense, the latterdoes not represent constructional information beyond amerely decorative level.
Primarily, a descriptive model is built for the promotionof ideas, client consideration and public relations ratherthan decision making, since the architectural designis generally perceived to be determined by this stage.As such, the descriptive model is not conducive tosigniﬁcant alterations but is used to convey qualitiesof external form and internal relationships. A typicalpresentation model is a literal representation of theproposed work of architecture at a reduced scale. Withinpractical parameters, the closer the materials of themodel approach those of the real building the better themodel will be – since it describes the architecture best, i.e.the most precisely. This, in turn, makes the descriptivemodel a particularly useful tool for communicatinga design to clients, members of the public, etc, whomay not have the same ability as architects to perceivespatial information through drawings and other two-dimensional media. The ﬁnality of these descriptivemodels is perhaps best illustrated by their use. Beyondthe realm of client presentations, such models of recentarchitectural designs – depicting both built and unbuiltworks – may be found within transparent protectivecases, usually set at eye level, almost in the manner ofmuseum exhibits. More recently, the increasing adoptionof digital fabrication methods into architecture educationand practice have meant that models may be producedthat directly correlate to the manufacturing processes ofthe ﬁnal building, especially in smaller scale projects suchas pavilions. As a result, the model of such a project maynot simply describe the overall composition but also theproduction and assembly processes very accurately and isoften referred to as a prototype whether built at full-sizeor not.