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Abstract: In the last years many studies concerning the evaluation of the thermal conductance of building elements via measurements have been carried out; this value has to be ensued from the analysis of recorded temperature and heat flux profiles. The determination of this property in situ would allow a more accurate a more accurate evaluation of the real heating energy demand of a building. Papers discussing different data analysis methods are present in literature and measurements on test components under real conditions and evaluations on different theoretical aspects by means of numerical simulations have been already developed. This paper aims at widening the existent literature of the in situ evaluation of the thermal conductance, through the discussion of the results of a measuring campaign which lasted four years on real buildings, and by comparing the reference specific thermal conductance (C) values with those computed on the basis of the measurements. Various tests on the same elements are discussed. Finally an analysis on the influence of the C value on the evaluation of the net heating energy demand of a building in different climates is presented. [Copyright &y& Elsevier]

Abstract: In the tropics, daylighting from a side window requires shading to intercept direct sunlight from the window whilst allowing penetration of daylight from sky. In this paper, daylighting from a double-pane glazed window with enclosed horizontal slats (slat window) was investigated for which it is situated on either north or south wall of a room. Full-scale experiments and simulations were conducted to characterize distribution of the interior daylight from the slat window under a real tropical climate. Performance of the slat window was evaluated in terms of the “useful daylight illuminance” (UDI), interior daylight availability and light power density (LPD) of an integrated dimmable lighting system. Empirical formulas were developed for determining annual average LPD values of the dimmable lighting system over its served area. The LPD value can be used with a reduced form of the energy equation of Thailand's building energy code to evaluate the reduced annual electrical energy consumption for accreditation of the daylight use in a building. The analysis of life cycle cost proved that the daylighting from the slat window integrated with the dimmable lighting system is cost effective. [Copyright &y& Elsevier]