Building Energy Optimization Using Climate-Responsive Design and Lightweight Cementitious Materials in Residential Projects

Aamer Sajjad, Sohail Anwar, Musarrat Ullah Khan Afridi and Zeeshan Ullah

Sustainable Business and Society in Emerging Economies, 2025, vol. 7, issue 4, 671-690

Abstract: Purpose: This study examines the energy inefficiencies of residential buildings in Pakistan, where poorly sealed envelopes and non–climate-responsive architectural practices result in excessive cooling loads. It aims to develop and validate, for the first time in Pakistan, a climate-responsive retrofit design framework integrating passive envelope optimization with experimentally verified Lightweight Aggregate Concrete (LWAC) to improve thermal performance and support sustainable housing in hot–humid climates.Design/Methodology/Approach: A representative 351.45 m² single-family dwelling was modelled in DesignBuilder using IWEC climate data for Karachi and Multan and calibrated against local residential load profiles. A comprehensive retrofit package—comprising R-20 roof and wall insulation, a reduced window-to-wall ratio (15%), low-U double glazing (1.5 W/m²·K), external shading, passive cooling, and enhanced cross-ventilation—was evaluated. LWAC samples were laboratory-tested for density, thermal conductivity, and compressive strength to assess their suitability as envelope materials.Findings: The integrated framework reduced Energy Use Intensity from 181.18 to 71.24 kWh/m²·year (60.7% reduction), equivalent to 38,639 kWh/year of avoided energy use, 377,188 PKR/year in utility savings, and 19,320 kg CO₂/year in avoided emissions. LWAC demonstrated 15–20% lower density, ~48% lower thermal conductivity, and ≥30 MPa compressive strength, confirming its structural adequacy and enhanced thermal resistance. The combined retrofit and LEED v4 measures resulted in a net premium of 336,298 PKR with a simple payback of 0.89 years, reduced to <0.7 years under a 6% annual tariff escalation.Implications/Originality/Value: The study provides the first validated climate-responsive retrofit and LWAC integration framework for Pakistan’s residential sector, demonstrating that high-performance, low-carbon housing is technically feasible, cost-effective, and rapidly scalable using local materials. The findings directly support ECBC-2023 implementation and offer evidence-based guidance for policymakers, designers, and developers seeking to promote sustainable construction in hot-humid regions

Keywords: Lightweight Aggregate Concrete; Energy-efficient retrofitting; Passive design; LEED v4; Hot-humid climate (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
https://publishing.globalcsrc.org/ojs/index.php/sbsee/article/view/3518/1940 (application/pdf)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:src:sbseec:v:7:y:2025:i:4:p:671-690

DOI: 10.26710/sbsee.v7i4.3518

Access Statistics for this article

More articles in Sustainable Business and Society in Emerging Economies from CSRC Publishing, Center for Sustainability Research and Consultancy Pakistan Contact information at EDIRC.
Bibliographic data for series maintained by Dr Rana Muhammad Adeel Farooq ().