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Thermal comfort and energy saving have become a priority for construction industry professionals. An important parameter of the comfort is the mean radiant temperature and its dependence on the building envelope. In the present research, a dynamic physical model has been studied in a climatic chamber, linked to the specific heat (C), density (r) and thermal conductivity (l). The heat capacity is usually quantifiable in small, homogeneous and uniform samples by the application of calorimetric methods. Consequently, the building energy consumption assessed through calorimetric methods, is often quite different from the energy consumption measured in situ. In this work an experimental model for the assessment of specific heat of real-size building components is proposed. Such a parameter was determined by measuring the heat flow through a building wall. The model has been validated by comparing the evaluated properties of known materials for different thermal gaps.

Thermal comfort and energy saving have become a priority for construction industry professionals. An important parameter of the comfort is the mean radiant temperature and its dependence on the building envelope. In the present research, a dynamic physical model has been studied in a climatic chamber, linked to the specific heat (C), density (λ) and thermal conductivity (λ). The heat capacity is usually quantifiable in small, homogeneous and uniform samples by the application of calorimetric methods. Consequently, the building energy consumption assessed through calorimetric methods, is often quite different from the energy consumption measured in situ. In this work an experimental model for the assessment of specific heat of real-size building components is proposed. Such a parameter was determined by measuring the heat flow through a building wall. The model has been validated by comparing the evaluated properties of known materials for different thermal gaps. [ABSTRACT FROM AUTHOR]

The advantage of adopting wall panels with lighter densities as precast wall panels (being developed in the recent past) needs to be assessed from the safety and serviceability point of view under loading. The paper presents a comparative analysis of multistoried buildings with reduced wall densities against ordinary brick walls. The type of building being considered for analysis is a G+5 RCC framed structure for residential usage. It was observed from the results that the final carpet area of the building increased when the panels were used in place of walls. With the decrease in the density of wall, no appreciable change in the volume of concrete was observed, but the savings in steel got reduced. [ABSTRACT FROM AUTHOR]

The strict energy saving standards are based on the declared values of the materials, i.e. U-value, thermal conductivity or thermal capacity. To this end, proper knowledge of the thermophysical properties of the wall components is needed, especially with regard to new lightweight technologies that are being used in building construction/refurbishment, under the dynamic conditions of the Mediterranean climate, where one of most important parameters of building materials is their heat capacity because of the influence of solar radiation energy. With this regard, the actual heat capacity value, obtained in laboratory tests, is typically quite different from the nominal one. So, this paper reviews several methods of calculating the heat capacities of materials and several worldwide applications, with the aim of providing an overview of the thermal behaviour of lightweight insulation materials and their implications for energy and indoor comfort. Finally, the authors propose a simple method able to evaluate the specific heat capacity of real scale building materials with a ~5% of uncertainty. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with the evaluation of thermal insulation performance of metal framed lightweight walls. This technology, more and more popular also in Italy, offers interesting advantages, but available commercial documentation lacks in reliable information about the real thermal insulation performance of the whole building envelope taking into account all the details and related thermal bridges. In other countries the available knowledge has been completed after long time and the recent growth of insulation performances requires something more than a simple Italian translation. In this paper the main envelope solutions are identified. The thermal transmittance has been calculated using a specialized freeware FEM application (THERM [1]) and the results checked with a commercial HAM application (WUFI [2]). The existing simplified methods have been extended in order to take into account also the most recent solutions proposed and realized, for a simple assessment of the real (corrected) avera ge thermal transmittance, far from singular points. Finally the main thermal bridges have been analyzed, optimized and used to calculate the average thermal transmittance of a standard façade module comparing it with the non-corrected U-value. [Copyright &y& Elsevier]