Recomendações para a Envolvente Térmica de Edifícios Residenciais Resilientes ao Clima: Uma Análise Aplicada sob Cenários Presentes e Futuros no Irão
Year: 2025
Type: dissertation
Abstract: In Middle Eastern countries, building energy consumption and associated carbon dioxide (CO₂) emissions exceed the global average. Iran exemplifies this issue, with its building sector’s energy demand currently five times higher than the global average, particularly in the residential sector. This excessive demand is primarily driven by a heavy reliance on mechanical cooling systems, such as air conditioning, due to the widespread neglect of energy-efficient building design—a consequence of decades of high energy subsidies that have promoted the unchecked use of fossil fuels and hindered the adoption of sustainable construction practices. With climate change driving rising temperatures, cooling demand is expected to escalate further, particularly in buildings with poor thermal performance.Reducing high cooling energy demand, for both current and warmer future climates, requires innovation in building design, particularly through improved thermal properties of building envelopes. As the primary barrier against extreme external heat, an energy-efficient envelope can significantly limit heat transfer, thereby lowering energy demand and greenhouse gas emissions.This research focuses on residential buildings, which account for the largest share of energy consumption in Iran’s building sector. It examines how global warming scenarios impact their thermal envelope design by assessing current thermal performance and exploring potential design adaptations. The study aims to develop a framework of high-performance solutions that not only reduce energy demand today but also ensure resilience to future climate conditions, guiding the evolution of energy-efficient design standards.To achieve this, a comprehensive literature review is conducted to identify strategies for enhancing building energy efficiency under both current and future conditions in Middle Eastern countries. Simultaneously, a real multi-story apartment edifice, representative of common residential buildings in Iran, is selected. The model is validated using recent energy bills, and the current energy demand is simulated. Then, a future weather generator tool is employed to create weather data for two timeframes—2050 and 2080, enabling an analysis of how climate change impacts energy demand under different Shared Socioeconomic Pathways (SSPs) scenarios. Following this, a sensitivity analysis (SA) is conducted on key envelope parameters using the selected apartment as a showcase building across six cities, each representing Iran’s major climate zones. These cities are grouped into heating-dominant, mixed heating and cooling demand, and cooling-dominant regions. In the end, the outcomes of the SA are compared with the current Iranian building code requirements for each climate group to recommend enhancements that support the long-term resilience and energy efficiency of multi-story residential buildings in the face of climate change.The results of the literature review guided this study to focus on specific thermal envelope parameters, identified as cost-effective solutions for reducing residential energy demand in both present and future conditions. Comparisons between future weather data, generated based on SSPs scenarios, and present-day data revealed that climate change leads to rising temperatures and declining relative humidity across all climate groups, varying in severity by region. For example, in the southern coastal regions of Iran, dry bulb temperatures are projected to increase by 1.5 °C to 4.5 °C, exceeding the anticipated global average, and are accompanied by a significant rise in energy demand. SA results identified six out of 18 thermal envelope parameters as the most influential across all cities under both present and future scenarios: thermal conductivity of floors, walls, and roofs; roof solar absorptance; window solar heat gain coefficient (SHGC); and window U-values. However, the influence of these parameters changes over time depending on the climate context. Influential parameters (such as U-values) become less important in heating-dominant cities as heating demand decreases. In contrast, in cooling-dominant regions, influential parameters (such as SHGC) become more critical as the demand for cooling increases under warmer future scenarios.Comparing these findings with national building code requirements revealed that Iran’s current mandatory energy efficiency standards are inadequate for current and future climates, necessitating stricter requirements just to maintain the same levels of energy consumption. Additionally, the city categorization system in the code should be reconsidered to better reflect the impacts of diverse climate challenges. Therefore, the study proposes a comprehensive framework for climate-responsive envelope design, tailored to various climate zones in Iran and similar regions, to enhance energy efficiency and ensure long-term resilience under future climate conditions.
Author: Fereidani, Nazanin Azimi
Language: English
Subfield: Building and Construction
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7127828647