Ziva Kristl*, Mitja Kosir, Ales Krainer

University of Ljubljana, Faculty of Civil and Geodetic Engineering,
Chair for Buildings and Constructional Complexes
Jamova cesta 2, 1000 Ljubljana, Slovenia
Tel ++386 1 4768 609, Fax ++386 1 4250 688
*E-Mail ZKristl@fgg. uni-lj. si

Abstract

At the Faculty of Civil Engineering, University of Ljubljana the senior year students attend course on bioclimatic design of buildings. In the academic year 2006/2007 they carried out a joint study [1] dealing with interaction among daylight levels and heating energy demand of their buildings in relation to properties of the applied glazing. Students also discussed the concept of passive house in relation to inside environment quality and compared the passive and the bioclimatic concepts. In the case of 27 student-selected buildings calculations showed that change from double to triple window glazing resulted in average reduction of specific heating energy demand (Qn/Au) by 14.4%. The same intervention at the same building configuration resulted in reduction of average illuminance level (Eav-eq) by immense 25.3%. Very similar results were obtained in an independent parallel study [2] carried out by the staff of Chair for Buildings and Constructional Complexes (KSKE).

Keywords: living environment, teaching, holistic approach

1. Introduction

In recent years sustainability in buildings has gained its importance in professional as well as in laic circles and it is often presented as the next big thing in construction industry. Just a brief look into the history of architecture reveals that sustainability has always been an integral part of construction. What has changed in the last century is that the technology, materials and speed of construction have altered dramatically. Despite of these changes in modern construction, sustainability should still be viewed as an integral part of design and building.

At the Faculty of Civil Engineering (FGG), University of Ljubljana (UL) the senior year students attend course on bioclimatic design of buildings. The lectures comprise building physics course, bio­climatic design principles, energy sources and innovative materials. The objective of the seminar is to nudge future civil engineers to use their knowledge in a holistic way. In this line of thought advanced technologies as well as old traditional principles are presented and the students are expected to apply them in their projects. In the academic year 2006/2007 the students were involved in a discussion about whether to use technological maximum for a specific area (e. g. reduction of heating demand) and if/how this decision influences other areas of internal environment design (e. g. daylighting). They carried out a joint study dealing with interaction among daylight levels and heating energy demand of

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their buildings in relation to U, g and tv values of the applied glazing. Because the reduction of thermal transmittance influences optical properties of glazing as well, we were primarily interested to what degree the decrease of U value deteriorates daylighting in a building. Lower U values also reduce the transmission losses of a building (but also solar gains), so we also compared the degree to which the energy balance of a building improves due to better glazing and considered if lower heat losses compensate poorer daylighting of internal spaces.