Indiscernibility and form: The design of Unit C as a critical inquiry into the guidelines for historical preservation
Indiscernibility and form

The design of Unit C as a critical inquiry into the guidelines for historical preservation


  • Per-Johan Dahl Politecnico di Torino, Department of Architecture and Design




Accessory Dwelling Unit, Emergent Building Type, Critical Practice, Zoning, Historical Preservation, Montage Theory, Design Research


This article explores the intersection between the indiscernible forces of urbanisation and the materialisation of architectural form. Taking the design of architectural concept for an Accessory Dwelling Unit (ADU) at Råå in Sweden as an applied research project, the article argues that new techniques are needed to analyse interactions between artistic intentionality and indiscernible forces, and to critically evaluate their impact on the form of buildings and places. The ADU is an emergent building type. Dubbed Unit C at Råå, the ADU was designed to be attached to a neo-classical villa. Unit C did not comply with the single-family residential codes in the zoning plan, thus a zoning amendment was necessary. As Råå has been designated a heritage site, this article takes the guidelines for historical preservation of buildings implicit in the zoning plan as an agent of the indiscernible forces of urbanisation. Adhering to critical practice, the article proposes architectural theory to be utilised as a pragmatic tool in innovative design processes. When designing the architectural concept of Unit C, the architects encountered a space for experimentation and negotiation in the guidelines for historical preservation. By critically analysing this space through architectural theory, the architects clarified relationships between the visual characteristics and the cultural heritage at Råå, which served to usher the architectural concept through the zoning amendment.

How to Cite

Dahl, P.-J. (2018). Indiscernibility and form: The design of Unit C as a critical inquiry into the guidelines for historical preservation. SPOOL, 5(1), 33–44.





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