Since the mid-1970s, urban development in Egypt has sprawled far from the distinguished compact arid built environment, as the court-yarded housing typologies that completed the vernacular picture of desert architecture have been discarded in the early 20th century. This has motivated urban microclimate research in Egypt. The main objective was initially to improve outdoor thermal comfort. Therefore, Egyptian research started with assessing different existing patterns for the sake of climate responsive and sustainable urban design practice characterized with low carbon, thermal comfort and energy efficiency in such a hot arid conditions. That is why the review workflow of this article has followed a design progress workflow that led to solving design complexities with regard to generating housing urban forms on a microclimate basis rather than an article regular review workflow in order to extract the research gaps and conclude insights. After discussing a general framework for generating housing sustainable design identified from the concluded gaps, the main conclusion is a vision and a call to integrate the Urban microclimate-Building passiveness-Renewables design dimensions, UBR, towards the evolution of a new era of energy efficient housing typologies and a 5th generation of Egyptian sustainable cities where the 1^st generation of new Egyptian cities started 1970s.

Urban climatology is a complex field owed to the intersecting parameters. In city planning, neighborhood fabric and vegetation plays a great role in modifying arid microclimates. This work presents an approach to enable urban designers to find the optimum land use parameters to achieve pedestrian thermal comfort. In this study, a model was developed based on ENVI-met simulations of two urban and suburban sites in Cairo, Egypt. Initial design parameters were; compactness degree, grass coverage, leaf area density, trees ground coverage, and asphalt and buildings areas. After regression analysis, the step-wise algorithm succeeded in creating the best fit of 94% R² and 92% adjusted R². The suggested Urban Design Comfort Model (UDCM) was examined using MATLAB to find the optimum design parameters. Optimum values were applied to generate primitive urban configurations using Grasshopper. The primitives were simulated again in ENVI-met to validate UDCM. The resulted value of Physiological Equivalent Temperature, PET at peak time was reduced from the initial result of ENVI-met (42.3 °C) in both sites to reach (38.7 °C) then (36.8 °C) after refinement with extra foliage. This approach, as a tool for urban designers, not only facilitates and speeds up urban form design process on a passive basis, but also provides deep insights on the development of UDCM considering all different city transects rather than two.