The international need towards increasing environmentally friendly buildings with less energy consumption and water wastage has led many countries to adopt the trend of building green roofs. This study is dedicated to investigating how to improvement the thermal performance of existed Egyptian residential buildings, by finding an alternative for regular green roofs, as existed Egyptian residential buildings cannot support regular green roofing loads because, it requires approximately 400 kg/m² for 10cm in depth soil thickness and the Egyptian roofs have been designed to withhold a cover load of 200 kg/m², the recommended solution should address Egyptian government major problems in energy consumption sector and water shortage sector. The primary goal of this research is to investigate the intensity of total solar radiation affecting the building's conventional external roof surfaces before it enters the building's internal space, affect it, and compare it with intensity of total solar radiation with the presence of hydroponic roof. The study showed that the use of hydroponic roof would enable planting leafy agriculture that is 90% less reliant on water irrigation plus, the total solar radiation decreased throughout the whole year with approximately 69% and energy consumption with approximately11.93 %.