Historic architecture is an inevitable component of cultural heritage. Historic structures as a resource and medium of collective memory and identity of a certain cultural community are potential historic monuments and therefore a subject of public interest requiring preservation and protection, i.e. sustainable development. Even though historic monuments and their values will always be affected by political, ideological and other manipulations, it is necessary not to give up the possibility of objectification offered by research in this field. Research of historic architecture (concerning architectural, artistic, and archaeological and/or restoration aspects) facilitates legitimating public interest in the preservation of architectural works and it is a necessity sine qua non in maintaining historic structures. Due to the fact that setting the value of historic structures has a rather ambivalent character as a result of the presence of diverse interests, the scientific perspective of the humanities (e.g. art history, archaeology, history) remains the only real and independent instrument for their objectification. Research of historic architecture provides an information potential, thus increasing the value of historic buildings and significantly influencing approaches to their restoration.
According to H. Eckerdt, J. Kleinmanns and H. Reimers there are two types of concept for treating historic architecture: those concepts accepting historic development until the present state and considering signs of this ageing process as a value (preservation, maintenance, conservation), and concepts aiming for modification of the historic development of the given construction, which try to various extents to reverse this process (renewal, reconstruction, renovation).
Renovation or adaptation of historic architecture offers architects the widest possibilities for creative work, e.g. when for certain reasons the original historic architecture needs to be extended by a new mass or detail. Eckerdt – Kleinmanns – Reimers differentiate two approaches relating to the preserved substance: addition (independent construction parts fulfill new requirements) and subtraction (creation of suitable base or substrate for a new form or shape by removing historic layers). In both cases we leave the platform of preservation in favour of free architectural design, resulting in everlasting arguments between architects and representatives advocating the preservation of historic structures. The research results are in this case relevant and obligatory for the architect in the preserved parts which are to be conserved, renovated or reconstructed. In the case of new substances, the research results facilitate understanding the historic and cultural context of the origin, formation, significance and functions of the given historic building or its environment, and also bear the corrective function. Research results can provide architects with a wealth of experience and inspiration for their own design work.
The presented examples of renovation of historic architecture show the ambivalence in utilization of research results. At the same time, they draw attention to the importance of a correct interpretation of gained knowledge for methodologists – the preservationists and creative architects who bear the main responsibility for maintaining historic architecture.