It is aimed to probe whether underlying formal regularities in urban metamorphosis may constitute potential basis of urban–architectural interventions. Urban design is described as a formal language. Underlying principles of urban transformation are argued as what constitute the grammatical structure of urban form and its change. Thus, socio–cultural significance of grammatical encoding inherent in the morphology of urban space is emphasised whereby geometrical relationships are utilised as instruments of spatial analysis. Urban transformation is analysed in terms of rule–based, compositional systems called 'formal grammars'. It is observed that there is a linguistic logic composed of an initial form of the design, a set of possible rules applied to this initial form, and recursive structures which define the sequence, order and location of the rules applied to it. Formal grammars are proposed as a helpful instrument of understanding to the broader framework of townscape and morphological analyses prior to urban design.
Keywords: urban design, morphology, semiology, transformation, formal grammars, urban transformation, townscapes