International Approaches to New Constructions in Historic Context (Study of Theories and International Agreements)

City is like a living entity، which regenerates constantly by constructing new buildings. With few exceptions، the character of cities have changed over time with the architectural styles fashionable in each period as well as the changing demands for their functionality. Most often، the character is a combination of styles and it is important that this evolution is maintained and the vitality of places can be extended. In fact، city is the result of different historical periods and includes historical loads of various periods; and، contemporary eras are in this process، too. Our constructions will form some parts of the city in future and will cause a layer in this inherited complex، and will make specification and identity of cities and will be an inheritance for posterity.  Although preservation is considered as a major step in revitalization of historic sites and buildings، ironically these sites benefit from being extended. In fact opposing construction of new structures on these sites could mean taking away the liveliness of the city and the long term standing of these sites as a historical place. In contrary، expansion and construction of new buildings on these sites maintains the history of the site to the new era and enrich its history.  New architectural styles and materials are often introduced into the city initially on the periphery and then in empty plots or as replacements for dilapidated buildings. Sometimes، existing buildings are adapted to the new styles. New architecture in an existing setting will set out to copy، mimic، integrate، harmonize with، contrast، juxtapose on or even compete with the existing context. Each situation may necessitate a different approach. However، construction of these new structures on a historic context is a very delicate task which requires well-planned regulations as these new structures link the contemporary architecture to the values and characteristics of the site.  Over the past few centuries a great afford has been carried out، thorough the world and particularity within the central Europe، for design of such regulations and legislations for revitalization and conservation of these sites. This has left a legacy of resolutions، recommendations and charters in this field around the world that are result of experience gained from a variety of approaches in this field in different countries.  In order to achieve a design guideline for new constructions in historic context، the purpose of this paper is review of ideas and theories، agreements and charters associated with the presence of new constructions in historic context. In this paper، we will review the theory of theorists that had more impact on the approaches. We will then look at the details of the agreements between the international bodies that directly or indirectly influenced these regulations and had key roles in their design. At the end، we will set a table which will be based on the approach of any of the agreements، and the evolution of this approach is discussed in international scale.