The impact of thermal transmittance variation on building design in the Mediterranean region

Abstract

Contrarily to what happens in northern European countries, buildings in the Mediterranean region are prone to overheating. Consequently, it is important to better understand the role of thermal transmittance of the building envelope elements in the airconditioning consumptions. This paper analyzes the effect of different U-values on the building design in the Mediterranean area. 192 000 residential buildings were randomly generated and the energy consumption assessed for sixteen distinct locations. It was found that, in northern Mediterranean locations, as U-values decrease, the energy consumption also decreases. However, in warmer climates, low thermal transmittances tend to significantly increase the energy consumption. Hence, the lower the latitude, the higher the most adequate U-values, due to the increase of the cooling demands. Additionally, geometry-based indexes were correlated with the buildings energy performance. For high U-values it was found that bigger buildings worsen the energy performance and larger windows tend to improve it. For low U-values, bigger North-faced windows are beneficial. There is an adequate interval of values for which the geometry has a lower impact, which is wider and higher for lower latitudes, thus meaning that not only the building performance improves but architects are also freer to explore alternative designs.

Building Envelope Prefabricated with 3D Printing Technology

“…Tables 3 and 4 show the values of thermal transmittance of the two types of blocks (the first with an empty air cavity, and the second with the air cavity filled with reinforced concrete). The values of thermal transmittances are compliant with the energy codes of most central and southern European countries [27][28][29].…”

Influence of the Improvement in Thermal Expectation Levels with Adaptive Setpoint Temperatures on Energy Consumption

“…The internal space of each dwelling is divided into a bedroom, a bathroom, a kitchen, a living room, and a corridor. The use of a virtual prototype of case studies to establish considerations and operational hypotheses has been used in various studies: (i) Grazieschi et al [66] used a virtual prototype of a two-story building to analyze optimal solutions in the life cycle of an autonomous building; (ii) Rossi and Rocco [67] designed a virtual test-room to analyze the influence of the periodic thermal transmittance and the internal areal heat capacity on the energy demand of the interior space; (iii) Rodrigues et al [68] and Fernandes et al [69] designed a wide variety of virtual prototypes of residential buildings using the Evolutionary Program for the Space Allocation Problem algorithm to assess the influence of thermal properties on energy performance; (iv) Jiru [70] and Abediniangerabi et al [71] analyzed different virtual prototypes of buildings included in the ASHRAE Standard 90-2010 to evaluate energy conservation measures; (v) Kim et al [72] analyzed the performance of the variable refrigerant flow and the rooftop variable air volume systems in a virtual prototype of an office building; (vi) O'Neill and Niu [73] used a virtual prototype of a single-family home to assess the effect of occupancy on energy performance; (vii) Shishegar and Boubekri [74] used a four-story virtual office building to…”

“…The internal space of each dwelling is divided into a bedroom, a bathroom, a kitchen, a living room, and a corridor. The use of a virtual prototype of case studies to establish considerations and operational hypotheses has been used in various studies: (i) Grazieschi et al [66] used a virtual prototype of a two-story building to analyze optimal solutions in the life cycle of an autonomous building; (ii) Rossi and Rocco [67] designed a virtual test-room to analyze the influence of the periodic thermal transmittance and the internal areal heat capacity on the energy demand of the interior space; (iii) Rodrigues et al [68] and Fernandes et al [69] designed a wide variety of virtual prototypes of residential buildings using the Evolutionary Program for the Space Allocation Problem algorithm to assess the influence of thermal properties on energy performance; (iv) Jiru [70] and Abediniangerabi et al [71] Regarding the virtual prototype used in the research, it is important to highlight that, to reduce the elements through which heat transfers take place, the case study corresponded to an intermediate floor, so that heat losses or gains produced through the roof were reduced. Given the aim of this study (analyzing the effect of the variation of setpoint temperatures on the energy consumption), both thermal properties and the load profile were the same in all locations, so there were no other factors varying the energy consumption: variations in the energy consumption were caused by setpoint temperatures.…”

Performance-based design of multi-story buildings for a sustainable urban environment: A case study

“…Besides being helpful to building design practitioners, performance-based approaches can also be used to study some building performance phenomena, such as the impact of different building indexes [31,32], to compare alternative construction systems [28], and to determine the best thermophysical properties of building elements [33][34][35].…”