Today several energy saving measures are being taken worldwide. As a component of these, the energy efficiency of the buildings should be increased. Given the high ratio of the existing, ineffective building stock, large-scale retrofit actions are going to be needed to reduce their energy usage. The historical districts and the heritage buildings stand as special part of the above question, as several limitations increase the complexity of their retrofit.
In present paper, the authors are introducing retrofit possibilities for the traditional apartment house type, widespread in the past Austro-Hungarian downtowns. A detailed methodology for complex renovation is divided to three main aspects: energy efficiency, monument protection guidelines and feasibility. By combining the above aspects, optimized renovation scenarios and their cost efficient financing implementation are surveyed.
Results show, that the energy saving and heritage respecting solutions are not economically feasible enough to be appealing for private investors. The retrofit, however, is much needed to increase the life quality of residents, save energy, and protect the unique architectural character, now constantly endangered by demolitions.
The authors suggest solutions for the above problem by creating possible financing scenarios, which can be used as a benchmark for preliminary decision making in case of a planned retrofit.
energy efficiency, historical building, heritage protection, energetic retrofit, decision support system, cost-benefit
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