The solar energy has been studied in greater depth than several studies have been conducted on  solar  energy  use  systems  in  recent  decades.  Studies  have  identified  photovoltaic  (PV)  systems  as  one of the most widely used and practical ways to use solar energy. One of the applications of such systems is their home application. Establishing photovoltaic systems on the roofs and gables of residential buildings have received a good appreciation around the world within the recent years as with the ever-increasing trend of urban life and subsequently the decrease of sufficient space for establishing such generators, now the necessity of using the dead spaces of rooftops of the residential buildings is sensed more than ever. Considering the potential of Iran due to its suitable geographic position and specially concerning Tehran metropolitan, having on average 5 hours of sunlight per day, and considering 2,214,498 residential units in Tehran, and thereby the great number of dead spaces in the rooftops of residential buildings, the necessity of conducting this research is felt even more. In this paper, while briefly introducing the network connected photovoltaic (PV) systems and the term of utilizing them on rooftops of buildings, precise and optimized design and layout of solar panels (including the number of rows, length and width of panels, distance between panels and the slope of panels to horizon) are provided using PVSOL software. Moreover, reviewing several printed articles while having a new attitude toward the field of renewable energies, we have presented the main and functional criteria and measures for installation of photovoltaic (PV) systems stationed on rooftops of residential buildings. Further, considering high diversity of the influencing indicators on the efficiency of photovoltaic (PV) systems in Tehran city, we have conducted a case study (Ekbatan residential complex) with the purpose of precisely implementing the indicators extracted from the present research.