Influence of the date of calculation of the insolation duration on the parameters of a compacted building

The influence of the date of computation of insolation duration on the acceptable mutual position of buildings and their height has been studied. The relevance of the research is explained by changing of the date of normative insolation computation from March 22 to April 22, which had been adopted in Russia. The study has been performed using 3D computer modeling of buildings and building of the fields displaying the duration of insolation on the building walls and surrounding territories. An algorithm of computing the insolation duration and of building the fields is given. It is demonstrated that when calculating the insolation with the new date of April 22, it is acceptable to increase the height of buildings and reduce the distance between buildings by 30 %, as well as to reduce the angle between a northern building wall and the parallel from 48° to 24°. The specifics of insolation for L-shape buildings has been revealed. It is shown that with shifting the calculation date from March to April, the insolation on inner walls decreases. The study of this special case has been performed. Dependencies have been built for duration of insolation on the inner walls of L-shape buildings depending on the computation date throughout the year, and on the increasing of the distance between the calculation point and the angle edge. The geometrical model explaining the revealed effect is provided. The examples are given, which show negative manifestations of the revealed effect. Here, new buildings, calculated for the insolation as of March 22, have been brought to unacceptable insulation as per April 22 norms. The studies have been performed in AutoCAD package using the system of automatic computing and building of insolation fields.