This thesis deals with the topic of attic constructions in founder time houses of Vienna. The focus of this work is based on the evaluation and documentation of those existing buildings in historic style, building codes and legal guidelines as well as the implementation of roof extensions. A review of the social and architectural development gives information about the founder time and defines the starting point of this paper. The current use of the building stock as soon as the conservation and restoration concept of the city are essential contents of this research. A key component is the collection of statutory provisions and guidelines for the attic constructions. In addition this exposition deals with the analysis of the different building types, facade designs and constructions of the historic period. Based on the evaluation of different restoration projects in Vienna, it is possible to make the attic projects contrastable. By inventories, data collections and discussions with engineers and architects, the data acquisition was realized. The focus of this thesis is particularly on complications between policy and implementation, impacts of the new roof extensions to the existing building as well as technical and constructive solutions.