thermal inertia

The GK environmental house is the first office building in Norway built according to the passive house concept. In such buildings, it is crucial to develop a ventilation strategy to reduce the energy use outside of the operating time. An optimal operating strategy has been developed for cold days, when the outdoor temperature falls well below 0 °C, which is presented in this paper. Indeed, these conditions correspond to the largest heat loss.

Few studies focus on commercial low-rise buildings which are often characterized by low-cost constructions materials and weak energy performances. For these large volumes, the heat transfers with the roof and the ground are prevalent. In this article, we show how the analysis of heat transfers through both the roof and the ground can achieve their thermal performance. The roof design and its opening systems is a key factor of the thermal and lighting performance.

A good level of thermal insulation and an adequate thermal capacity of the building envelope are essential to achieve good energy performance. Many studies have been conducted about this topic, mostly focused on the reduction of energy losses, peak load control and energy savings. Nevertheless, very few studies were realized addressing both insulation and inertia of the building envelope in a thermal comfort perspective, and taking into account the combined effect of different ventilation strategies.

This paper presents the energy savings thatcould be obtained by the appropriate design ofthe building in terms of morphology, thermalinertia and glazed area. Based on an extendeddatabase of values obtained by simulations, thisparametric study gives a new approach for thearchitects or design engineers as supportguidelines in the very first stage of their projectsin finding efficiently energetic solutions.One of the analyzed parameters is the buildingshape coefficient which is defined as the ratiobetween the volume of a built form and itsexternal heating losses area.

This work is based on an extended research from a doctorate thesis developed in a partnership between Federal University of Rio de Janeiro (UFRJ) in Brazil and INSA of Lyon, Thermal Centre of Lyon, Building Physics Team (CETHIL/ETB) in France. The purpose is to examine the envelope building design considering the outside microclimate to achieve a comfortable indoor climate. The context of exterior climatic features and site location are considered, taking in account an indoor discomfort sequence over a typical warm season.