Earth Block Houses of Historic Centers. A Sustainable Upgrading with Compatible Repair Materials

Earth structures have been continuously used in construction from prehistory until nowadays (33% of worldwide houses), due to their low cost and easy production, without high energy embodied materials. They were constructed with various techniques and materials which depicted apart from the regional traditions in building, the construction philosophy of the past, inspired from the respect to environment and saving of materials and energy resources. In many towns of the South East Europe there is a stock of earth block houses of vernacular architecture. Most of them have been abandoned and destroyed or reconstructed with concrete or cement based materials, altering completely their original characteristics. Nowadays, there is not a unified policy for the preservation of this significant part of the common European Cultural Heritage due to:-The tradition of manufacturing earth masonry has been vanished-The lack of scientific knowledge regarding the restoration and repair materials of earth structures by using adequate and mild interventions.-The lack of regulations regarding the proper compatible materials and techniques.However, the consolidation, upgrading and reuse of these earth masonry houses in the urban plan of modern cities, is of great importance for the cultural identity and development of them. In the paper the main characteristics of these houses have bee recorded, as well as the main damages and problems they confront. Then a series of techniques and materials compatible to the existing ones is proposed and commented properly from the aspect of performance and cost effectiveness.