PLEA

Steven Beckers and Pierre Lallemand conceived the refurbishment of the European Headquarters in the centre of Brussels. With a low-energy design, sensitive in its choice of materials, the building uses environmentally friendly strategies and meets all modern comfort and environmental standards.

This paper describes the Architectural Design Studies undertaken by Mario Cucinella Architects as part of a three year JOULE research project into the application of Passive Downdraught Evaporative Cooling (PDEC) in non-domestic buildings. The objective of the research was to develop a viable passive alternative to air-conditioning through architectural design, experimentation and performance assessment. MCA’s architectural research investigations involved 1) designing and constructing a full-scale experimental building to explore passive ways of capturing and conducting air through a tower into test cells and 2) designing a new office building in Catania Italy to develop the application of PDEC and undertake building performance assessment. Experimental work included wind tunnel tests, computer simulations and daylighting tests. The result of the design work is a new energy efficient building typology that is both a successful application of the evaporative cooling system and a direct architectural response to scientific problem.

This paper describes part of the work being carried out by CRES, in the frame of the EU-funded JOULE project “PRECis : assessing the Potential for Renewable Energy in Cities”. The main aim is to develop simplified parameters that describe the microclimate and environmenal performance of different urban textures. One of the roles of CRES within the team is to describe simplified parameters for the use of vegetation in the urban context, which can eventually be used irrespective of site-specific characteristics for different climatic contexts and urban textures. Of particular interest is the effect of vegetation on microclimate : thermal effects, as well as the effect of vegetation on solar and daylight access. These affect the microclimate of the existing open spaces as well as the energy use of the surrounding buildings for heating, cooling and lighting, through shading, evapotranspiration, etc. Simple parametric studies are examined, to identify the thermal impact of vegetation in the urban environment, at the scale of the urban block, particularly as far as the reduction of air temperature is concerned.

With rapid urbanisation, often without climate responsive guidelines, cities in the Tropics are progressively falling short of sustaining outdoor life. In order to re-establish and sustain life outdoors, it is important that we try to make urban spaces comfortable as far as the ambient climate permits. In order to ascertain conditions of comfort for outdoor spaces, we need to define comfort for outdoors. This paper presents findings on outdoor comfort based on field investigations conducted in Dhaka, a city in the wet-Tropics. Findings from a survey conducted on a large number of randomly selected people from urban spaces are presented. The findings include factors affecting comfort outdoors for Dhaka and a comfort regime based on environmental parameters for urban outdoors is presented. Interestingly, comfortable ambient climate leads to comfortable indoor environment, particularly with regard to free running buildings. With regard to mechanically controlled indoor environments, a comfortable outdoor produces lesser stain on energy environment relationship. By defining conditions of comfort for outdoor environments, an important step towards achieving sustainability of our urban environments can be made.

Whilst research into indoor thermal comfort is well advances, the impact of outdoor thermal conditions has received less attention. The thermal conditions encountered in outdoor urban space are a major determinant of the patterns of usage of the space and are created in part by the surrounding buildings. This paper describes a research project which is attempting to develop indices of outdoor thermal comfort which can be used in the evaluation of the impact of new urban development upon the quality of the environment in urban spaces.

We present here a theoretical study about the relationships between comfortable and pleasant ambiences. The notion of comfort is not sufficient for the study and design of ambience. Ambience is defined here as the way the environment affects a subject. Subjects are naturally affected by a global ambience. However, for the analysis, we distinguish between luminous, aesthetic, thermal, acoustic… ambience. Comfort definitions exclude the notion of tension and psycho-physiological disturbance on subjects, whatever its level may be. The question of pleasant ambience is naturally not fully answered. However, one way to define a pleasant ambience especially includes the notion of tension on subjects affected by an ambience. The case of the house on the cascade by F L Wright perfectly illustrates this point. This house is situated on a waterfall whose acoustic level is above all norms. Therefore this house is not comfortable. However, it is widely recognised and taught as a reference for its pleasant ambience, especially for the contribution of the acoustic ambience. In this case, the comfortable and pleasant sides of ambience are conflicting. As modern technologies are improving, artificial lighting and ventilation, for example, can lead to perfectly comfortable ambience. However, it is widely recognised that natural lighting and passive ventilation are more pleasant. We develop this discussion on the basis of the results of a study on qualifications of luminous ambience and on other theoretical and technical works. We believe that this investigation is nowadays important because the technological sides of ambience are improving : comfortable ambience may be designed, but are they pleasant ? We think that a very global view on ambience is now needed.

This paper presents the findings of a research project investigating daylighting quality through its perceived effect on the everyday user of a space. The subjects participating in the experiments are asked to describe their perception of the daylit environment through a standard questionnaire. The physical measurements taken in these daylit spaces are then correlated with the subjects’ sensations, in order to identify which quantifiable parameters affect daylighting quality and others which are non quantifiable. The main results suggest that quality is in fact the main criterion by which users judge the daylighting in a space. A new index named LD is derived, which correlates successfully with user responses. The paper concludes by presenting the impact of the findings on daylighting design.

It is important that the countermeasures to reduce CO2 emission during the housing usage phase be examined. In this study, the factors under various daily activities concerning the CO2 emission were simulated, in order to examine a more effective countermeasure. Then, it was confirmed that CO2 emission, that can be controlled by residents, occupies a large portion. For this reason, it was also found that the life style influenced the amount of CO2 emission considerably. These results suggest that the improvement of the residential life style is important for the general reduction of the CO2 emission.