Globally, there is an increase in the severe climatic events that are happening, such as the increase in global temperature, flooding, wildland fires, and sea level rise. This necessitates the need to adopt sustainable design principles and solutions to develop better and healthier future cities. The Egyptian government in corporation with civil society in recent years, through many attempts, tried to implement the notion in the local society. Thus, the paper will explore multiple solutions that can achieve three main parameters that correlate with each other: thermal comfort, energy consumption reduction, and carbon dioxide (CO2) emissions decrease. This will be discussed for the residential sector and by using New Cairo in Egypt as the research case study. The study will reveal several significant findings on two levels; Level one is the building's footprint which includes building form in relation to orientation mainly in the early design stages. Where it was found that the rectangle with the courtyard had the best results among the six simulated forms. And level two is the building design that explored the building envelope; façade and roof in relation to Indoor Environmental Quality especially when retrofitting the research case study. Where it was found that green roofs are a better strategy for enhanced sustainable results in a hot arid climate than the Phase Changing Material (PCM). This will be achieved throughout adopting a systematic analysis with the help of the Energy Plus (Design-Builder) simulation tool.