A comparision of new Turkish thermal insulation standard (TS 825), ISO 9164, EN 832 and German regulation

Abstract

Nowadays, the most common characteristic of all regulations and buildings is that heat energy requirement of a building is calculated and evaluated for the whole building, not as a sum of those for individual building components. In this paper, first, the recently revised Turkish standard is described in general, and then compared with the ISO 9164, EN 832 and the German regulation. The calculation procedures presented in the standards are evaluated, based on the results of three different types of buildings. The new TS 825 is an application of ISO 9164 in every respect. It uses the same equation, same restriction and same flexibility. EN 832 is basically similar to the ISO 9164 and so is the new TS 825. The most important difference in EN 832 is that solar energy gain is calculated in quite detail including passive solar gains, as well as direct solar gains. This approach gives more accurate results but need huge and detailed database. German regulation is harmonious with ISO 9164, EN 832 and TS 825 only from the point of view of principles and concepts. However, it is a very simplified one, the calculation method defined in the German regulation gave Q year far from the actual heating energy requirement of buildings for the countries with moderate climate. The main differences between the calculation methods presented in the standards are “the acceptance of climatic data,” “the calculation method of internal heat gains,” “the calculation method of solar heat gains” and “the acceptance of the air change rate values.” The effects of parameters and the building types on the energy demands are discussed in order to determine which parameter should be constant but which ones should be variable, to obtain more simple but accurate results, and to show to designers the parameters to be effectively controlled to decrease the energy requirements of the buildings. Independently of building type, the higher the area of component, the more influential is its U-value on the Q year except ground. Ground has always the least effect on the Q year. The effect of air change rate is high being almost similar for all types of buildings, however air change rate affects Q year slightly less at the terraced office building than the others. With lower U-values of wall and window, the effects of window area and window directions on the Q year of detached buildings are minimized. Terraced buildings are more sensitive to window area than the window directions. It is clear that the increase in south window area, for all types of buildings, has slightly more effect on Q year than the increase in north, east and west window areas. The effects of r and g on the Q year increase, when the heat loss decreases but solar gain increases. Therefore, for modern buildings, to accept these parameters as a constant is not fairly significant.