Energy efficiency and environmental sustainability issues draw more attention as the visible signs of the current climate crisis become more evident. One of the industries most important to transition to sustainability benchmarks is construction – our built environment is one of the biggest consumers of embedded and operational energy. According to the 2018 Global Status Report of the Global Alliance of Buildings and Construction group, “In 2017, the construction and operation of buildings consumed 36% of the energy produced on a global scale, and carbon dioxide (CO) generated as a result of energy consumption2) accounted for almost 40% of its emissions.” As can be understood from this, the efficiency of our buildings affects almost all other aspects of our lives in terms of sustainability.
When the importance of the built environment in our ecological health started to be realized, the first reaction was to build new structures using the latest technologies. The demolition of inefficient, old buildings and the replacement of modern-looking, “efficient,” and “cool” new buildings have been accepted as a solution to reduce the role of the construction industry in the climate crisis for a while, and it has been shown as proof that the industry has taken the necessary steps and set good examples. Today, prestigious architects demolishing old buildings and projecting new designs in their place has made us believe that we can continue without changing anything in the operation and mentality of the sector, and that the climate crisis is a problem that can be solved with insulated glass and solar panels.
However, Since most of our built environment is already “built”very important questions have been raised: Should non-energy efficient buildings be demolished automatically? Can they be adapted? What would be the consequences of demolishing these structures?
In general, the answer given by the conservation discipline to these questions is as follows:from industry [elektrik ve su tesisatının yaygınlaşmasından] previous buildings were already built sustainably (with natural methods given priority) and did not require the use of fossilized carbon in their construction or operation.” (English Heritage, 2012) Since many historical buildings were built before energy sources such as electricity, will consume as little energy as possible designed in such a way. These methods constitute solutions, many of which are now referred to as “passive”, such as natural lighting and increasing insulation using carpeting. Passive solutions are now preferred to installing new technologies because they consume much less energy and materials.
More importantly, demolishing a structure and building a new one requires an exorbitant amount of energy. Instead, adapting existing (historical or non-historical) structures not only prevents this energy consumption, but also allows us to preserve the character, values and memories that are one with our built environment.
What is embedded energy?
Two types of energy are consumed in a structure, embedded and operational. Embedded energy covers all the energy spent for the construction of the building, this includes the energy obtained from sources such as electricity, oil, heat required for the mining and processing of the required minerals, the production of the building materials, their transportation to the construction site and their assembly, as well as the manpower required in the whole process. Operational energy, on the other hand, includes uses such as light and electricity required for the use of the building during or after construction.
When a building is demolished and replaced with an “energy efficient” one, only operational energy is reduced, but this is usually a very small amount compared to embedded energy. the existing structure its buried energy is completely wasted However, the destruction itself, the removal of the resulting rubble, and the rebuilding process consume a lot of energy. In addition, “demolition of a standard, two-story detached house creates 200 tons of waste.” (Lubeck, 2010, p.10) In order to compensate for these losses, the new structure must reduce its operational energy excessively, and it will most likely not be successful. Therefore Adapting and using existing structures is the most ideal recycling method. (Lubeck, 2010, p.18). In the now famous words of the American architect Carl Elefante,
“The greenest building is the one that already exists.”
A well-designed maintenance/reconditioning/restoration project can reduce the operational energy consumption of an existing building as much as a new building. The National Trust for Historic Preservation’s research branch, the Preservation Green Lab in the US, states that “advancing options to retain and retrofit existing windows is the most cost-effective way to reduce a home’s energy consumption and lower its carbon footprint.” (Saving Windows, 2016) By applying one or two simple methods, such as insulating an existing opening with window tape or attaching double glazing to the frames, the savings to be achieved with a new, ‘high energy performance’ window can be achieved (Saving Windows, 2016).
How do environmental sustainability and architectural preservation overlap?
In 2015, UNESCO adopted the Sustainable Development Goals, which are expected to be adopted by 2030. One of these 17 goals (SDG 11) is to “make cities and settlements inclusive, safe, resilient and sustainable. [getirmeyi]” aims (UNESCO, 2015). The fourth of the nine sub-articles of SDG 11 is to “support work to protect and preserve the world’s cultural and natural heritage,” and the sixth is to “advance per capita environmental impacts of cities, including air quality and the management of urban and other wastes, by 2030. reduction” (UNESCO, 2015). In this sense, architectural conservation and ecological sustainability studies are actually working towards the same goal..
SDG 11 reflects where architectural conservation has begun to acquire in the ecological literature. There has been a persistent belief that historical buildings are inefficient, which has been used as a justification for demolishing them and replacing them with new, ‘energy efficient’ structures. However, since the aim of energy efficiency is to use less energy to perform the same functions, this is just as achievable in a historic building as it is in a new building. Many historic buildings have passive methods not seen in contemporary buildings, as they were built before active heating/cooling methods or electric lighting. Because, adapting historic buildings to be energy efficient is a much more ‘sustainable’ method than replacing any new buildings.
Energy Efficient Adaptation of Historic Buildings
We don’t need to sacrifice the characteristics of a historic building to make it energy efficient. Many experts agree that these features and historical values can be compatible with energy efficient technologies, a strategic approach is sufficient at the design stage. The Cultural Heritage Preservation Association is working to prove this phenomenon through the KORU Project.
One of the main outputs of the Capacity Building in the Protection of Cultural Heritage (KORU) Project has been the energy efficient restoration of a traditional stone house in Mardin. The solar energy system used in Tamirevi is a good example to explain the so-called ‘dilemma’ between historical identity and contemporary energy needs.
Mardin is one of the most suitable cities for solar energy in Turkey in terms of average daily solar radiation value and sunshine duration (Eskin, 2006, p.76). In addition, the flat roofs traditional in the region form the unique silhouette of the historical city of Mardin. In order to evaluate the solar energy potential, photovoltaic panels were placed on the roof within the scope of the KORU Project.
The most important decision regarding photovoltaic panels was to place them in such a way that they would not spoil the historical silhouette of Mardin, that is, they would not be seen from the street. Since the Tamirevi is a registered building, otherwise the project would not have been approved by the Conservation Board. After the interviews with the mechanical engineers, it was determined that the photovoltaic panels could operate with full performance even when they are placed at a 10⁰ angle so that they cannot be seen from the street. Thanks to such discussions and compromises, the energy-efficient adaptation of historic buildings can be done without compromising the character of the building or its surroundings.
Is architectural protection sufficient? What else can we do?
It will unfortunately take a long time to make the majority of our built environment energy efficient, as extensive repair and retrofitting of an existing structure is an expensive process. In this period, it is necessary to take other steps, for example, capacity building and awareness raising studies can be carried out on energy efficiency in historical buildings.
It is necessary to educate people from different professions and age groups in order to raise awareness. The first of these They are architects, engineers, technicians and craftsmen/masters in the construction sector. Trainings should be carried out regardless of the public or private sector, and they should focus on sustainability and energy efficiency in historical buildings. In this process, different professional groups, such as architects and mechanical engineers, who are mostly accustomed to working separately in the field of construction, should be trained together and be provided to understand each other’s perspectives through case studies. Special attention should be paid to the masters who can be ignored during the decision stages during the trainings, and in this way, the continuity of the traditional crafts required for the continuity of the historical buildings should be ensured.
The second group to be trained historic home owners and monument caretakers. The definition of historical monument caretakers includes religious officials of mosques, churches or synagogues as well as maintenance, administration, cleaning or security workers in monumental buildings. Since people in this group are responsible for making decisions about the health of the building in case of a sudden risk or during the daily maintenance process, they can significantly reduce the operational and repair costs of historical buildings.
The third group, such as journalists, teachers, local government workers and tour guides, professionals who can train otherscovers me. The slightest awareness in these groups can create a butterfly effect in their environment.
One of the main outputs of the KORU Project was these trainings. KORU’s capacity building activities have been further enhanced with the restoration of Tamirevi, which is used both as a training site and as a good example. Thanks to the Tamirevi, KORU added a fourth group to the list: the public, who came to visit the construction site and later the completed exhibition, also benefited from the project.
The KORU Project’s model energy efficient historical building study has proven that architectural preservation and ecological sustainability are not opposite concepts. The causes of the climate crisis are not only the use of air conditioners or natural gas/plastic consumption, but a mentality that is dependent on continuous consumption. The habits of utilizing and not trashing the resources we have must start with our buildings first.
2018 Global status report: towards a zero-emission, efficient and resilient buildings and construction sector. (2018). Global Alliance for Buildings and Construction, p. 9. www.worldgbc.org/sites/default/files/2018%20GlobalABC%20Global%20Status%20Report.pdf
Energy efficiency and historic buildings: application of part L of the building regulations to historic and traditionally constructed buildings. (2012). English Heritage. https://historicengland.org.uk/images-books/publications/energy-efficiency-historic-buildings-ptl/
Eskin, N. (2006). Solar energy research and development in Turkey. Journal of Plumbing Engineering, 91, p. 74-82.
Lubeck, Aaron. (2010). Green restorations: Sustainable building and historic homes. Canada: New Society Publishers.
Saving windows, saving money: evaluating the energy performance of window retrofit and replacement. (2016). https://forum.savingplaces.org/viewdocument/saving-windows-saving-money-evalu