Yehya Serag

The 15-minute city model, a visionary approach to urban planning, envisions neighbourhoods where residents can access all essential daily needs – work, education, healthcare, shopping, and leisure –within a 15-minute walk or bike ride. This study assesses the challenges and opportunities of implementing the 15-minute city model in Downtown Cairo, Egypt. The study examines the current state of public spaces, transportation, and walkability in the area through ethnographic research, including extensive field observations and frequent attendance at design workshops with developers, as well as numerous site visits and in-depth semi-structured interviews with diverse stakeholders. Stakeholders included the developer of the Cairo House project, the Cairo Bike project manager, urban researchers, tourists, residents and business owners within the study area. Data were analysed using thematic coding to identify recurring patterns and conflicting perspectives. The findings reveal significant challenges, including traffic congestion, limited public spaces, and inadequate pedestrian and cycling infrastructure. The study explores potential solutions, including enhancing public transportation, creating safe and accessible environments for pedestrians and cyclists, promoting mixed-use development, and developing vibrant and accessible public spaces. The main findings underscore the significance of community engagement and participatory planning in ensuring the successful and equitable implementation of the 15-minute city model within this unique and historic urban context.

Retrofitting “nearly-zero energy” heritage buildings has always been controversial, due to the usual association of the “nearly-zero energy” target with high energy performance and the utilization of renewable energy sources in highly regarded cultural values of heritage buildings. This paper aims to evaluate the potential of turning heritage building stock into a “nearly-zero energy” in hot, dry climates, which has been addressed in only a few studies. Therefore, a four-phase integrated energy retrofitting methodology was proposed and applied to a sample of heritage residential building stock in Egypt along with microscale analysis on buildings. Three reference buildings were selected, representing the most dominant building typologies. The study combines field measurements and observations with energy simulations. In addition, simulation models were created and calibrated based on monitored data in the reference buildings. The results show that the application of hybrid passive and active non-energy generating scenarios significantly impacts energy use in the reference buildings, e.g., where 66.4% of annual electricity use can be saved. Moreover, the application of solar energy sources approximately covers the energy demand in the reference buildings, e.g., where an annual self-consumption of electricity up to 78% and surplus electricity up to 20.4% can be achieved by using photo-voltaic modules. Furthermore, annual natural gas of up to 66.8% can be saved by using two unglazed solar collectors. Lastly, achieving “nearly-zero energy” was possible for the presented case study area. The originality of this work lies in developing and applying an informed retrofitting (nearly-zero energy) guide to be used as a benchmark energy model for buildings that belong to an important historical era. The findings contribute to fill a gap in existing studies of integrating renewable energy sources to achieve “nearly-zero energy” in heritage buildings in hot climates.

Retrofitting heritage buildings for energy efficiency is not always easy where cultural values are highly concerned, which requires an integrated approach. This paper aims to assess the potential of applying passive retrofitting scenarios to enhance indoor thermal comfort of heritage buildings in North Africa, as a hot climate, a little attention has been paid to retrofit built heritage in that climate. A mixed-mode ventilation residential building in Cairo, Egypt, was selected as a case study. The study combines field measurements and observations with energy simulations. A simulation model was created and calibrated on the basis of monitored data in the reference building, and the thermal comfort range was evaluated. Sets of passive retrofitting scenarios were proposed. The results (based on the ASHRAE-55-2020 adaptive comfort model at 90% acceptability limits) showed that the annual thermal comfort in the reference building is very low, i.e., 31.4%. The application of hybrid passive retrofitting scenarios significantly impacts indoor thermal comfort in the reference building, where annual comfort hours of up to 66% can be achieved. The originality of this work lies in identifying the most effective energy measures to improve indoor thermal comfort that are optimal from a conservation point of view. The findings contribute to set a comprehensive retrofitting tool that avoids potential risks for the conservation of residential heritage buildings in hot climates.

This study aims to develop an integrated classification methodology for retrofitting that preserves both energy use and cultural value aspects in hot climates, especially, in North Africa, as a hot zone, which lacks retrofitting initiatives of built heritage. Despite the number of existing methods of classification for energy purposes, little attention has been paid to integrate the perceptions of cultural values in those methods. The proposed methodology classifies heritage building stocks based on building physical characteristics, as well as heritage significance levels, and then later integrates the outcomes into a matrix to propose sustainable retrofitting scenarios based on three dimensions, i.e., heritage value locations, types, and heritage significance level. For validation, the methodology was applied to the heritage residential building stock along with a microscale analysis on a building in Khedivial Cairo, Egypt. The findings include extracting twelve building classes, providing a reference building for each class, and a detailed catalogue of the extracted reference buildings that includes retrofitting scenarios for creating energy models. The originality of this work lies in integrating cultural values in a building classification methodology and providing a list of sustainable retrofitting scenarios for reference buildings. The findings contribute to fill the gap in existing building classifications, more specifically in hot climates.

The Arab Spring transformations have caused tangible impacts on the urban environment throughout the Middle East with varying levels. In some cities in countries like Libya, Yemen and Syria, deliberate and accidental destruction has taken place, resulting in severe transformations in the image of these cities that could be considered as lasting or difficult to amend. In some cities, the damage caused to urban built environment could be considered a co-lateral damage as a result of internal fighting between the people and their regimes, or the fighting between the different factions in the country or from external interference of regional or international powers. Urbicide, which is defined as a deliberate destruction of cities is also another form of damaging the built environment or the city image, in which parties in an internal conflict tend to destroy symbols or quarters of their rivals to inflict a tangible damage to their social and moral believes. The impacts on the built environment and the image of the city, can result as well from non-destructive measures, for example changes in land uses or decisions to demolish specific buildings that belong to the former era will also result in a clear change in the city image. This paper highlights the types of transformation of the city images that took place as a result of the Arab Spring revolutions. The cases discussed in this paper focus mainly on cities from both Syria and Egypt. This highlighting is done in regard to the nature of change, as mentioned above, the violent transformation in the case of Syrian cities and few cases in Egypt and the nonviolent transformation with the examples from Egypt. In case of the Syrian cities the transformation is caused and sparked by the civil conflict, however the course of reconstruction of these cities after the conflict ends is argued to take one of three paths; reconstruction, renovation or redevelopment. While in case of the nonviolent transformation that is taking place already in Egypt, the nature of change was affected by political, social and security aspects, which in turn had direct impacts on the images of the Egyptian cities after the Arab Spring revolutions.