The case study seeks an optimal solution for preserving the cultural values of a functionalist building so that it fulfils the legislative essence of the protection of a historic building and, at the ...same time, contributes to the improvement of its thermophysical properties. The paper focuses on the degree of the application of energy performance requirements for the adaptive reuse of a historic building. The efforts to preserve cultural values (architectural, aesthetic, the value of the authenticity of an area and its building constructions, etc.) in legally protected buildings often do not permit the application of building construction processes such as those used in ordinary older buildings. The research responds to a situation where a building with historic values, built in a functionalist style (the 1940s), permits variants of the surface treatment of the facade so as to not disturb the essential stylistic values of that facade and, at the same time, reduce its energy demands to the required value.
Heat demands for heating have a significant effect on the energy needs for heating and thus on the overall energy need of a building. The heat demands depend on the efficiency and quality of the thermal protection in buildings. In the case of cultural monuments, the calculation of the thermophysical properties of building structures forms the basis for determining the heating and cooling demands. Building structures and their elements that form the building envelope must meet current and demanding thermophysical requirements in accordance with the applicable standards, if technically and economically feasible. When restoring cultural monuments in the Slovak Republic, it is not required to meet requirements for energy efficiency. On the other hand, it is necessary to verify the thermophysical requirements in accordance with the applicable standards in each specific case.
The paper responds to a continuing interdisciplinary discussion on this topic. The analysis is conducted within the scope of the KEGA 016STU-4/2017 project.
This article is closely related to the oldest article titled Contribution to Active Thermal Protection Research—Part 1 Analysis of Energy Functions by Parametric Study. It is a continuation of ...research that focuses on verifying the energy potential and functions of so-called active thermal protection (ATP). As mentioned in the first part, the amount of thermal energy consumed for heating buildings is one of the main parameters that determine their future design, especially the technical equipment. The issue of reducing the consumption of this energy is implemented in various ways, such as passive thermal protection, i.e., by increasing the thermal insulation parameters of the individual materials of the building envelope or by optimizing the operation of the technical equipment of the buildings. On the other hand, there are also methods of active thermal protection that aim to reduce heat leakage through nontransparent parts of the building envelope. This methodology is based on the validation of the results of a parametric study of the dynamic thermal resistance (DTR) and the heat fluxes to the interior and exterior from the ATP for the investigated envelope of the experimental house EB2020 made of aerated concrete blocks, presented in the article “Contribution to the research on active thermal protection—Part 1, Analysis of energy functions by the parametric study”, by long-term experimental measurements. The novelty of the research lies in the involvement of variant-peak heat/cooling sources in combination with RES and in creating a new, original way of operating energy systems with the possibility of changing and combining the operating modes of the ATP. We have verified the operation of the experimental house in the energy functions of thermal barrier, heating/cooling with RES, and without RES and ATP. The energy saving when using RES and ATP is approximately 37%. Based on the synthesis and induction of analogous forms of the results of previous research into recommendations for the development of building envelopes with energy-active elements, we present further possible outcomes in the field of ATP, as well as already realized and upcoming prototypes of thermal insulation panels.
The thermal energy consumption for heating objects is one of the main parameters deciding their technical and structural solution. Reducing energy consumption is realized in various ways. The most ...used method is passive thermal protection, that is, increasing the thermal insulation parameters of the envelope constructions and optimizing the operation of the technical equipment of the buildings. There are also methods of active thermal protection to reduce heat leakage through non-transparent parts of the building envelope. Active thermal protection (ATP) is a dynamic process that applies primarily to building structures with integrated energetically active elements that fulfill one or more functions in mutually exclusive operating modes of energy systems and heat sources, such as thermal barriers (TB), large-scale heating/cooling, long-term heat/cool storage, capturing solar energy, and energy from the surroundings or even recovering heat in the cold season or cold in the warm season and other combinations. The research area focuses on analyzing active thermal protection’s energy potential. The methodology is based on a parametric study of dynamic thermal resistance (DTR), and heat flows to the interior and exterior from ATP for the investigated envelope of the experimental house EB2020 made of aerated concrete blocks. Such constructions generally show a consistently high DTR of 11.8 to 30.8 ((m2·K)/W) at a low mean heat transfer temperature of 10 to 16 °C, corresponding to the thermal insulation of 300 to 1000 mm. In the case of ATP storage heating with an average temperature of the heat-carrying substance of 30 °C, the heat flow into the interior of the investigated structure would be only 2.31 W/m2. Therefore, they are only suitable for a thermal barrier and heat/cold accumulation. Based on the synthesis and induction of analogical forms of the results of previous research into recommendations for the design of individual energy functions of ATP for perimeter structures of buildings, we present heat flows to the interior/exterior when changing the material of the layers towards the interior from ATP and describe possible variants of the development of building structures with integrated energetically active elements.
The basic concept in the design of buildings with zero energy consumption is, in addition to high-quality thermal properties of the building envelope, also a correct and efficient system of heating ...and hot water preparation in residential buildings. One of the basic concepts when designing heating systems is a zone heating system. It is a system that brings effective regulation according to heating zones. In practice, the question sometimes arises as to whether zone regulation of individual rooms in small family houses is necessary. That is whether in such buildings, zone heating is not an unnecessary investment cost. In this paper, we analyze the effect of zone heating in two types of heat transfer systems on the internal operating temperature in the individual analyzed zones, which are interconnected by an internal partition structure. It is a verification that even in smaller spaces, zone heating has a significant potential for energy savings.
Reduction of energy use in buildings is an important measure to achieve climate changes of mitigation. It is essential to minimize heat losses when designing energy efficient buildings. For energy ...efficient building in a cold climate, a large part of the space heating demand is caused by transmission losses through the building envelope. In compliance with the today's trend of designing sustainable and energy-saving architecture, it is necessary firstly to solve the factors influencing the energy balance. This year the subsidy for houses has been valued at € 8,000. The condition is that the building is classified in the energy class A0 according to the Energy Performance Act. Energy class A0 characterizes nearly zero energy buildings. The main concern is for the public to become interested in such buildings. The subsidy is designed to reward and promote those buildings that their heat and technical characteristics and modern technical equipment that meet energy class. In addition to a good plan to raise the profile of such buildings, there has been a lot of speculation to help make buildings in energy class A0. They are mainly owners of family houses where there is no gasification and are forced to have electricity as a source of heat and hot water. Electricity has a high primary energy factor, which means that buildings do not have to be approved.
During the design of the external cladding, it is possible to use different materials and compositions. One of these possibilities is also a ventilated facade, which consists of a supporting ...structure, a thermal insulation, a supporting grid, an air gap for ventilation and a cladding layer. The construction of the supporting grid in the ventilated facade must be mechanically anchored into the supporting structure of the external cladding. This mechanical anchoring causes 3-D point thermal bridges in the external cladding itself. Therefore, the aim of this work is to assess and analyze the influence of these 3-D point thermal bridges on transmission heat losses through the external cladding. A Finite Element Mesh analysis has been used for this analysis. Different types of external cladding compositions were modeled in the simulation program, and the effect on the heat transfer coefficient was determined. In addition to the analysis of the existing anchoring systems, an innovative solution has been suggested that is more economical and easier to implement. The results show that the application of anchors and their number impacts significantly on the thermal properties of the envelope. The difference between the anchoring element with a thermal insulation pad and the patented method is minimal. This is a 1.29% difference. The last variant was a proposal (patent) that the anchoring element is only plastic-coated and thus its thermal engineering properties are improved, which is manifested mainly in heat conduction but also from the radiant point of view, as plasticizing the emissivity changes. Compared to the perimeter cladding without the ap-plication of an anchoring element, the heat loss increases by 29.37%. In addition to the energy savings, there are also financial savings. While the plastic pads costs about EUR 0.3, the plastic coating (patent) represents a price of around EUR 0.03. If we had a building with 10,000 m2 of wall area where 6 pieces of anchors per 1 m2 are applied, the savings would be EUR 16,200. Such savings are already significant. The conclusion of this work is that these point thermal bridges have a significant impact on the overall transmission heat loss coefficient and therefore they have overall heat demand and energy demand.
Rising living standards have led to a significant increase in building energy consumption over the past few decades. Therefore, along with sustainability requirements, it is essential to establish an ...effective and precise energy demand model for new buildings. In principle, energy demand in buildings is very important plan to pre-calculate and that is one of the reasons why it is supposed to be precalculated for most of the sustainable buildings. Net Zero-Energy Buildings (NZEBs) have received increased attention in recent years as a result of constant concerns about energy supply constraints, decreasing energy resources, increasing energy costs and the rising impact of greenhouse gases on world climate. Promoting whole building strategies that employ passive measures together with energy efficient systems and technologies using renewable energy became a European political strategy following the publication of the Energy Performance of Buildings Directive recast in May 2010 by the European Parliament and Council. In Net Zero-Energy Buildings (NZEB) is necessary to calculate all factors that influence on energy need for heating. However what is still underestimated is the consideration that the energy performance of any building component is the result not only of its thermophysical properties but also of how are all the components installed and connected to each other. Thermal bridging in buildings can contribute to a multitude of problems. One of the details that create thermal bridges is balcony. This paper is focused to calculate Balcony systems (isokorb) impact on energy need for heating and economic valuation of balcony systems in residential building.
In compliance with the today’s trend of designing sustainable and energy-saving architecture, it is necessary to firstly solve the factors influencing the energy balance. In this respect, the thermal ...bridges in buildings constitute a crucial factor. In case of their occurrence, the use of construction and insulation building materials is significant for finding the solution. The aim of this paper is to analyse the thermal bridges in buildings constructed on the basis of light constructions. The subject of analysis was an implemented wood frame house with common sandwich construction, designed in a low-energy standard. The house analysis is divided in theoretical and experimental part. The house in question has been directly exposed to dynamic boundary conditions. In order to analyse the thermal bridges, critical details have been selected methodically, verified by thermography. The experimental and theoretical results were compared by the simulation method for calculating critical surface temperatures. Both the measurements and results show how attention shall be paid to this issue at the project stage already. With increasing demands for overall energy balance of buildings, it is necessary to exactly define the critical details and consider the thermal bridges in the project documentation already.
Is it possible to live in a ruin while meeting the contemporary construction and engineering requirements for the interior and preserving its authenticity at the same time? The ruin of outbuilding is ...located in a protected area of the classicist manor-house from the second half of the 19th century. In order to sustain the continuity of the character of such historical environment, the goal was to preserve its appearance as much as possible. The proposed adaptation of the outbuilding ruin for residential usage applies an experimental concept of reconstruction using progressive and renewable building materials and technological procedures. In this contribution, we deal with the designed reconstruction of the building while preserving authenticity and considering the energy requirements applicable in our legislation. Under the current marginal conditions, it is not only the energy needs for the heating season that need to be solved. The project shall be considered comprehensively, i.e. including the energy needed for cooling. The submitted building concept calculates with energy for both the heating and cooling season. The question is whether or not it is possible to design the NZEB concept for the reconstructed building observing the contemporary construction and engineering requirements for the interior while preserving its authenticity?
The trend in the components of residential buildings is low energy demand buildings in relation to the minimum costs spent by users for their operation. The main aim of their construction is to ...improve the energy economy of buildings, to reduce the environmental load in energy consumption, to improve the quality of the interior, to ensure the minimum cost level in the operation of buildings and their maintenance in the life cycle. The consequence of increased energy prices and the possible implementation of tax policies in the countries of Europe is more frequently designing and implementing energy self-contained buildings. This means that energy necessary for the general use of a building can be produced in it to certain extent. The concept of such buildings is not only in high quality heat insulating properties, but also in suitable installed devices utilizing alternative sources. The objective indicator of saving and proof of the required level of a building is an analysis of its real energy consumption. The paper analyzes the energy consumption in a specific house which, in the design phase, met the criteria for designing a nearly zero energy building. The analyzed building has a high thermal protection and uses photovoltaic energy as an alternative source. The main aim is to evaluate the concept of the designed nearly zero energy building and to assess it in relation to the really consumed energy.
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