As the serious consequences of the climate crisis are becoming more visible around the world, the link between sustainability and cultural heritage is getting stronger. Many theoretical measures and solutions are discussed, but their results have not yet been widely reflected in practice. The KORU Project has put a concrete man in the field of sustainable conservation and implemented Turkey’s first energy efficient restoration project and became one of the pioneering examples in the practice of this field.
The sustainability of historical cities was among the main objectives of the project. For this reason, a traditional building in Mardin was chosen within the scope of the project. The building called Tamirevi became a model for the application of climate sensitive systems in a historical building. Creating a culture of reuse in the field of sustainability is a very important action, and the reuse of buildings by adapting them to new functions should undoubtedly be a part of this culture. Universal legal processes on this subject are now being renewed to include the construction industry, and legal regulations in Turkey are being updated accordingly.
Making existing structures more environmentally friendly is a necessity today. Because we don’t have the luxury of spending energy on new buildings instead of adapting existing ones. When it comes to historical buildings, when we protect the building itself, we protect the buried energy that has already been spent in the building. In this context, Tamirevi is an important model for future restoration projects. While the building, which was originally a residence, was re-functionalized as a cultural structure, contemporary technologies were integrated into the building without compromising its originality.
Designing a Restoration Project Based on an Energy Efficiency Approach
The adaptation of the Tamirevi restoration project through environmentally friendly methods took place in several stages. The first step was taken by investigating the energy consumption habits of traditional buildings in Mardin. For this purpose, 20 historical buildings were selected and a survey was conducted with the households and the common problems of these buildings were determined. The fact that the historical city center of Mardin is located on a steep rocky hill causes the lack of proper heating infrastructure in the city, so heating can be said to be a common problem for all houses. According to the survey results, air leaks and water leaks in buildings were the second biggest problem. For these reasons, it turned out that regular maintenance and the lack of proper insulation greatly reduced the quality of life in the dwellings.
After the survey results were evaluated at stakeholder meetings, it was time to measure the current energy performance of the building. As expected, it was recorded with the energy identity document that the U values were quite high. Since many historical buildings are equipped with their own sustainable systems, it was very important to understand the original working scheme of the Tamirevi. Because the priority in the protection approach was to support the existing systems with passive solutions, while minimizing and lightening the mechanisms to be used for mechanical and electrical systems, so as not to overload the structure.
In terms of renewable energy resources, Mardin is geographically and climatically located in a very suitable position for the use of solar energy systems. After deciding on the energy source as solar energy in this way, the final stage of the design process was to decide on contemporary heating, cooling, ventilation and installation systems suitable for the structure.
Implementation Processes for an Energy Efficient Historic Building
Since energy efficient technologies designed for the built environment often target new buildings, the first step in the implementation process was to rethink these technologies over a historical building such as the Tamirevi. In addition, resources in this area include universal standards, but climate parameters vary around the world. Therefore, while the general theoretical framework for the application did not change, the necessary interventions had to undergo changes based on local materials and techniques.
The architectural team of the Cultural Heritage Preservation Society received assistance from sustainable architecture consultants working for Edinburgh World Heritage in the design and implementation processes. Due to the above-mentioned reasons, necessary changes were made to adapt the report, which includes recommendations on energy efficiency, prepared by the consultants for the Repair House, to local historical and climatic conditions.
The primary intervention was the application of a building envelope suitable for the structure. It was not possible to cover the masonry stone walls of the Tamirevi on the inside or outside in any way, as it would cause them to lose their originality, so thermal insulation was applied on the roof and on the ground floor. Considering the results of the surveys, it was critical to improve the apertures to lower the U-values. The original windows of the building had been lost in previous periods, so it was necessary to produce new windows. A double-glazed window design was prepared based on the traditional window typology. The carpenters of the Mardin Museum Woodworking Workshop, who had previously participated in the cultural heritage trainings of the KORU Project, produced the windows based on this drawing. Claiming that Tamirevi would be a suitable and repeatable model for its environment could only be achieved by feeding from the local resources here, so it was very valuable that the applications made were created by the use of materials unique to the region and the knowledge and experience of local craftsmen.
One of the most critical decisions made during the process was regarding the placement of the photovoltaic panels. In order to achieve maximum performance in energy, the panels were mostly positioned to face south in applications. However, in the Tamirevi application, the visibility of the panels had to be minimized. Because in a future scenario where solar energy is widely preferred and applied, south-oriented photovoltaic panels on the roofs would risk becoming an element that would damage the historical silhouette of Mardin. As a result, this risk was eliminated by placing the panels at a low angle facing east-west.
The air source heat pump was decided as the most suitable heating system for the climate and geography of Mardin. Heat pumps can provide heating and cooling without the need for any fossil fuels and can produce heat energy 1.5 to 3 times the electrical energy they consume. Hot or cool water coming from the boiler of the heat pump travels through the pipes placed under the floor and traverses the building. Running the M&E systems under the floor was one of the main design decisions at Tamirevi in order not to damage the original texture. The electric current also proceeds through the pans under the floor and reaches the electrical components in the house.
The repair house originally had small openings on the front and side for ventilation. These small windows are still used for natural ventilation, but a heat recovery ventilation system has been installed for areas that natural ventilation cannot reach. This system provides energy gain through the circulation of clean and polluted air.
In addition, a simple top cover was modeled and produced to prevent the overheating problem on the south façade and to provide more comfortable use of the terrace in summer. A landscape arrangement was made with potted plants in the courtyard and on the terrace, and the plants were created to create a cooling effect in the open areas. Two vines to be placed on the terrace will replace the awning in a few years, creating a natural solution for shade.
Beyond the implementation process, a hall of the permanent exhibition located on the ground floor of the Tamirevi was designed to explain energy efficiency in historical buildings. Exhibition panels are placed in niches in the room and are presented with a movable tablet placed on the 1/25 scale section model of Tamirevi. Visitors can take virtual tours on the tablet and take a closer look at the energy efficient solutions at Tamirevi.
With the completion of the applications, the combination of all the aforementioned systems made Tamirevi compatible with today’s conditions and extended its lifespan. The Tamirevi stands as tangible proof of the feasibility of an energy efficient restoration project and hopes to inspire and guide similar projects in the future. This process, which is as challenging as it is instructive, has revealed the need for a multidisciplinary approach in the field of sustainable conservation. Thanks to the repair house example, historical buildings are one step closer to being at the center of climate sensitivity in the construction sector as much as new buildings. Not only the application itself, but also the presentations and publications about Tamirevi helped to spread the impact of the study on national and international platforms. Considering the physical, social and political difficulties in its region, Tamirevi has managed to become an exemplary practice in its field by integrating contemporary technologies into its holistic architectural preservation approach and now awaits its visitors.