A large amount of work devoted to electric supply system load determination . But most of the load detection methods and the corresponding coefficient values were found many years ago and are outdated, for example, electric supply system for new many residential house. At this time, changed not only loads the value but also its character - thus leaving the impact on the calculation methodology used and the coefficient values. Latvenergo Distribution Network staff realized loads survey to a wide range of 24 office buildings and apartment buildings in the over two years. The results presented in the form of official instructions. This paper continues the ongoing theme and dedicated to improving the methodology of calculation. Particular attention paid to the relationship with existing methods of calculating loads, the coefficient physical interpretation and possible changes in the characteristics of the range. Work up estimates of loads methodology for multi-family homes, office buildings, apartment buildings with offices and / or shop floor, modifying the sorted chart method. Shows the load factor g physical sense, its relationship to start, overload and peak coefficients, designed to determine this curve, and the use of the methodology. Based of housing and building protective apparatus choice , the correlation with loads and peak loads .The method for design engineers and engineering staff in connection with the operation of apartment buildings and control.