This work describes a study aiming to establish the impact of the increase of the building envelope insulation upon the thermal performance of buildings. A particular emphasis is placed upon the consequences in terms of higher temperatures in summer, potentially leading to increased needs for installation of air-conditioning. This study also describes the coupled influence of other parameters that can reduce overheating, like solar shading and ventilation. The methodology is based on parametric studies obtained through simulations. The comfort analysis methodology is based on the adaptive approach. The results show that, with added insulation, it is necessary to control solar and internal gains more closely to avoid overheating in summer. Results also include the requirements to avoid airconditioning, in terms of window shading for each level of insulation and internal gains.

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This article discusses the retrofitting of public spaces in compact urban areas bearing in mind the need for outdoor thermal comfort. The role of paving materials and vegetation was focused on a field survey undertaken at a square in Porto, Portugal. The potential for microclimatic improvement of different combinations of paving materials and vegetation was explored through simulations with ENVI-met. The options, objectives and results of the simulations and an evaluation of Life Cycle Assessment related factors were addressed and discussed. The best improvement scenario was defined stressing the relevance of ‘cool’ paving materials and vegetation and the need for a sustainability analysis throughout the design practice.

Building energy codes are considered to be an effective policy tool for energy reduction worldwide. However, their application and effectiveness are still limited in developing countries. In Egypt, the residential sector is promising for energy savings, as most of the existing residential buildings are aged with low thermal performance and non-conformance with energy codes. This study aims to raise the awareness of promoting the Egyptian residential energy codes among construction parties, especially end-users, by quantifying the environmental impacts, in terms of energy savings and thermal comfort enhancement. Moreover, it attempts achieving a nearly zero energy building by integrating several energy-efficient measures with renewable energy sources. Thus, in this study, a typical residential building in Cairo was chosen for simulation. The simulation results revealed that applying energy code instructions for building envelope, lighting enhancement and increases in cooling set-points, from 24 °C to 25 °C, saved 37.85% of annual electrical energy and resulted in a cooling reduction of 50.53%. Furthermore, the photovoltaic system incorporation succeeded in transforming the building into a nearly zero energy building. Concerning thermal comfort, the application of passive energy-efficient measures significantly influences indoor thermal comfort, with a 30% reduction in discomfort hours during the cooling season, which represents the main concern in hot climate regions.