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What's the definition of Passive Climatic Design? for architecture?

What's the definition of Passive Climatic Design? for architecture help... please answer in detail.

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1. Traditional buildings often mitigated the exterior climate,even if ‘comfort’ was not always achieved at all times of the day or in all seasons. Modern construction offers the technical possibilities to reach very good comfort though heating, cooling and other kinds of air conditioning. We therefore tend to forget the old knowledge about how to adapt our houses to the climate passively. Heating and cooling of buildings account today for high energy consumption. Higher living standards lead to active climatization of buildings such as offices and hotels, and also residences. For the building to be energy efficient it is necessary to control the input of energy through regulatory systems and/or through ‘passive’ techniques. ‘Passive’ techniques, normally requires more interaction, monitoring and knowledge by the user, and is therefore more sensitive to human factors, though technically simpler and more reliable. When designing an individual building, the general outdoor climate is to be regarded as a given condition, though there might be climate change over a long time, and that it may be possible to affect the micro-climate by urban and building design. For thermal comfort, the building must act as a barrier,transforming the outdoor climate to conditions suitable for indoor activities. The typical design process is a weighing of conflicting demands, such as between passive and active climatization, between privacy and solar access, between cross-ventilation and noise reduction, etc., to reach a satisfactory compromise. While passive heating, mainly based on solar energy, has resulted in a wide range of technical solutions such as solar heaters and photo-voltaic cells, the evolution of passive cooling has been much slower. Principles of passive cooling are: shading, reflection, insulation, reduction of internal gains, ventilation, fans, and tightness of buildings. Heat reduction is best achieved by excluding unwanted heat rather than removing it later, often by air conditioning. Where wood was scarce, vaults and domes were normal in traditional architecture. Cylindrical and dome roofs have a higher heat transfer coefficient and larger area than flat roofs of the same base. The solar energy absorbing area is nearly the same, whereas the convection heat transfer area is higher for the curved types. There are thus no big differences between the constructions as such. Traditional buildings in hot climates often have high rooms, especially those with domes or vaults which add to the room height, and thus also to the volume. Lower ceiling heights also reduce construction costs, and in combination with insulation, give better indoor climate in colder seasons. In regions where ambient temperature has greater influence on comfort than ventilation, orientation with respect to the sun is important. A north-south orientation of the main facades is preferable, since the summer sun penetrates facades and openings only marginally in these directions, while in winter when the path of the sun is lower, there is possibility of solar access. Thermal comfort can be created by increasing air speed through cross ventilation, which promotes evaporative cooling of moist skin. Placement of openings for inlet and outlet of air is essential for directing the air current to the occupation zone. As a rule of thumb, night ventilation can create an indoor maximum temperature of 7–8 K below the outdoor maximum. During daytime, when the building is closed, the thermal mass is cooler than the indoor air, making the operative temperature lower, further enhancing the comfort. For more , read this article by Hans Rosenlund. Very interesting.... http://www.heatinghelp.com/greenpdfs/29.pdf