It is estimated that currently as many as 75% of the buildings built before 2000 in the European Union have poor energy performance. Improving it is crucial to saving energy and achieving the planned zero-carbon building stock by 2050. In short: properly insulating a building translates into less energy required to heat it, which means lower carbon emissions into the atmosphere and lower bills. So how do you improve a building's energy performance?
The way to increase energy efficiency is through thermomodernization, which means, for example, replacing or modernizing the heating system, insulating the partitions — walls, ceilings, roofs and floors, or replacing woodwork. The thermomodernization of the Polish cube in Jasło — a flat-roofed single-family house typical of the communist era, the likes of which steaks can still be found throughout the country — was handled by Marcin Łukasz Tęcza, an architect from the MLT architecture & urban design studio, who works in Luxembourg on a daily basis.
Ola Kloc: The project involved the thermal modernization and adaptation of a typical 1960s cube. What were the biggest challenges in adapting the building to current guidelines related to thermal energy demand and consumption?
Marcin Łukasz Tęcza: The biggest challenges in adapting the building to current thermal energy consumption guidelines were mainly ensuring effective thermal insulation and maximum elimination of thermal bridges, as well as using energy-saving technologies.
In this project, this required the use of modern yet compatible materials with the existing structure. We used 20 cm thick rock wool to insulate the facade and cellulose wadding for the ventilated ceiling.
We encountered difficulties with the local availability and acceptance of non-standard insulation materials, which required convincing local companies and a logistical effort to bring in specific products, such as the Kingspan insulation used around the windows and balconies.
The final challenge was to comply with subsidy programs, which affected the project's schedule, particularly the postponement of the installation of the heat pump and photovoltaic panels. Unlike in Luxembourg, where I work every day, home insulation subsidies in Poland depend on income.
terrace
© Marcin Łukasz Tęcza
Ola: What solutions striving for energy efficiency did you apply to this property?
Marcin: In order to save energy, I mainly proposed installing new thermal insulation of the building using ecological materials, installing energy-efficient windows with appropriate wind and waterproofing, using renewable energy sources and optimizing heating and ventilation systems.
As an architect-urbanist, I know that the pursuit of energy savings is not limited to the design of new passive buildings. It is also important to make efficient use of existing structures by modernizing and adapting them to modern energy requirements. The project involves the superstructure of an existing structure to create an additional residential unit in the inner city. This strategy allows for an increase in density without taking up new land, which is also a step toward sustainability.
minimalist home interior
© Marcin Lukasz Tęcza
Ola: What advice would you give to architects who undertake such projects?
Marcin: For architects undertaking thermal retrofit projects and introducing energy-efficient solutions, it is crucial to take a comprehensive approach at the initial planning stage. Here are some tips that can make such projects easier:
- Understanding the building: before starting the project, I recommend conducting a detailed analysis of the building and its surroundings. This will allow you to identify key challenges and opportunities related to its location, history and current condition. An essential step is to perform an energy audit, which will reveal the most critical areas from an energy loss perspective. Based on the audit, priorities for action can be identified and appropriate technologies selected.
- Integrate sustainability principles: this includes not only energy efficiency, but also the use of environmentally friendly materials and attention to the health of users and minimizing environmental impact.
- Using low-carbon technologies such as heat pumps and photovoltaics to significantly reduce energy consumption.
- Optimizing HVAC systems: efficient heating and ventilation systems are key to thermal comfort with low energy consumption.
- Eliminating thermal bridges and thermal insulation: this will improve the building's energy balance and avoid unnecessary problems.
- Interdisciplinary cooperation with experts from different fields (construction, installation, energy) will allow creating a coherent and comprehensive project that will fully exploit the potential of available technologies and materials.
- Open communication with the investor: it is important to maintain clear communication with the investor from the very beginning regarding expectations, technical possibilities and potential additional costs associated with the use of energy-efficient solutions. It is also good to inform about available financial support programs that can reduce the initial investment costs.
It is crucial to take a holistic approach, which will enable the integration of modern energy solutions while preserving the architectural aesthetics and functionality of the building.
Ola: How do functional solutions and room layouts from the 1960s work today? What required your intervention?
Marcin: Functional solutions and room layouts from the 1960s can still be effective, but they often need to be adapted to modern living standards and needs. In my design, I optimized the room layouts to better suit current requirements, while maintaining the character of the original building.
In the era of home office and open source, it was interesting to add a common room with direct access to the garden, accessible to all residents, which can be used as a temporary extra room to be shared among tenants — for remote work, as a temporary guest bedroom or a common room for recreation.
The house has been divided into separate apartments
© Marcin Lukasz Tęcza
Ola: You work in Luxembourg on a daily basis, what is the situation in the market there related to thermal modernization of existing buildings and introduction of energy-saving solutions in architecture?
Marcin: In Luxembourg, as in other European countries, there is a growing environmental awareness and a need to reduce energy consumption. Therefore, thermal modernization projects and the introduction of energy-efficient solutions are becoming mandatory.
Institutions such as Klima-Agence, which specializes in energy audits and energy efficiency consulting, play an important role in the process of thermomodernization. Their experts offer comprehensive analyses, helping building owners identify areas for energy efficiency improvements and select appropriate technologies. With their support, more and more buildings are being upgraded to reduce energy consumption and improve occupant comfort.
In Luxembourg, thermal modernization and the introduction of energy-efficient architectural solutions are actively supported by the government through various grants and subsidies. Any new home construction must meet the standards of a near-zero energy building (nZEB) as of January 1, 2017. The key here is to combine modern building technologies with available financial support programs to maximize benefits for both building users and the environment.
Particularly in urban areas where space is limited, it is becoming increasingly important to bring existing buildings up to current energy requirements to reduce energy consumption and improve quality of life.
Luxembourg is also planning to introduce new zoning regulations aimed at limiting the concreting of new land and reducing areas covered with impervious materials. These measures are being taken to protect the environment and ensure sustainable and balanced development.
Ola: Thank you for the interview.
