Evaluating commercial signs in historic streetscapes: the effects of the control of advertising and signage on user’s sense of environmental quality

The subject of this study is the visual damage caused by commercial signs in historic city centres, and its effects on user perception and evaluation of these places. The research problem concerns the lack of a general approach to guide and control commercial signs in historic city centres, based on the perception and evaluation of users from different urban contexts. The aim of this study is to identify those aspects related to the operation of commercial signage controls and physical characteristics of commercial signs and buildings that should be taken into account in the development of a general commercial signage approach. This general approach can help national, regional, and local authorities of different urban contexts design and implement commercial signage controls. This research begins with the development of a theoretical and conceptual framework by analysing concepts related to (i) visual quality and user perception and evaluation of the built environment, (ii) formal and symbolic factors linked to the streetscape that influence aesthetic judgments, and (iii) non-physical variables related to the operation of commercial signage controls, such as consumer culture, city centre management, marketing the city and urban tourism, and by reviewing current commercial signage approaches adopted in different urban contexts. The empirical investigation explores user perception and evaluation of commercial signage controls in three different historic city centres. The Environment Behavioural research field, a multiple method survey design, and a multiple case study approach are adopted. The combination of documentation review and archival records, systematic observations of physical characteristics of commercial streets, questionnaires, interviews, and focus group proved to be efficient to answer the research questions and achieve the research aim. The city of Oxford in England, and the cities of Gramado and Pelotas in Brazil were selected as case studies. One of the main conclusions of this research is the definition of a series of aspects related to the operation of commercial signage controls and the physical characteristics of commercial signs and buildings that need to be taken into account in the development of a general commercial signage approach. This study also identifies common patterns of perception and evaluation among individuals from different urban contexts and user groups (lay people and professionals). A possible future stage of research in this topic can be the application of the same methodology in other case studies to verify whether the same universal views found here will be verified. If the findings of this Ph.D. research can be found consistently between users from other urban contexts, then urban design principles that incorporate user perception and evaluation of commercial signage controls and historic city centres can be addressed as theoretical concepts to combat visual pollution in historic cities across the world.