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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.

The indoor visual comfort of subjects faced with indoor ambient lighting varies with the position of the subject and is not constant over time. Average performance indexes, such as the mean value of Daylight Factor and Daylight Autonomy, are commonly used to analyse lighting distribution. These indexes, however, don’t properly take into account either the spatial or the time distribution of values affecting the non-uniformity of environmental lighting. Indeed, these are limited to the definition of a mean value or to the assessment of time availability of daylighting. This paper examines spatial and temporal non-uniformities in indoor lighting as possible causes of discomfort for occupants. The goal is to propose and verify possible supplementary tools to integrate traditional methods of evaluating ambient indoor lighting Use of the entropy theory with a probabilistic approach can help to obtain more detailed information about the environment. The authors have developed a case study of several sample environments and have analysed the relationships between lighting parameters and typical indices of information theory. Results show that this approach could be a useful way for predicting possible indoor visual comfort issues and for developing a preliminary assessment to a sustainable building design.