Sustainable Façade Retrofit: A Case Study of Grand Metro Mall

Thesis Abstract

The rapid growth of retail complexes and aging building envelopes in urban centers has intensified energy consumption and indoor environmental disparities, prompting the need for sustainable façade retrofit strategies that balance energy performance, occupant comfort, and economic viability. This study addresses the problem of suboptimal energy efficiency and thermal discomfort in Grand Metro Mall due to outdated façades, limited daylighting optimization, and poor boundary performance that collectively elevate operating costs and greenhouse gas emissions. The aim is to evaluate and implement a retrofit package for the mall’s façade that achieves measurable reductions in energy use while maintaining visitor comfort and aesthetic value. Specific objectives are (1) to quantify baseline energy consumption and thermal comfort levels associated with the current façade; (2) to design an optimized retrofit solution comprising high-performance glazing, shading devices, and insulation retrofit with an accompanying façade management control strategy; (3) to model long-term energy savings and payback for the proposed package using dynamic energy simulation; (4) to assess environmental, economic, and social impacts through a multi-criteria decision framework; and (5) to develop a replicable methodology for similar regional retail contexts. A mixed-methods approach was adopted, combining quantitative energy simulations with qualitative stakeholder insights. The population includes Grand Metro Mall’s technical staff, tenants, and customers, with a purposive sample of 40 facility managers and 60 tenants for interviews and surveys, alongside a 12-month energy monitoring dataset from sub-metering of lighting, HVAC, and façade-related loads. Data collection instruments comprise 1) façade performance measurement protocols, including infrared thermography and in-situ U-value assessments; 2) energy modeling inputs derived from comprehensive site surveys, weather-normalized load profiles, and thermal bridge mapping; 3) a semi-structured interview guide to capture operational constraints and acceptance of retrofit options; and 4) a structured survey to gauge perceived comfort and willingness to adopt retrofit measures. Validity and reliability are enhanced through triangulation, pre-testing of instruments, and inter-rater reliability checks for thermal measurements. Analytical methods include regression analysis to correlate façade features with energy consumption, time-series analysis of sub-meter data to establish baseline and post-retrofit performance, and dynamic energy simulations using EnergyPlus for the proposed retrofit package under typical meteorological year (TMY) data. A life-cycle cost analysis (LCCA) and a multi-criteria decision analysis (MCDA) employing the Analytic Hierarchy Process (AHP) will compare retrofit variants, incorporating capital cost, maintenance, energy savings, greenhouse gas reductions, and occupant satisfaction. A conceptual model integrating the drivers of façade performance, retrofit technologies, and stakeholder acceptance will guide interpretation of results. The theoretical underpinning draws on the Theory of Planned Behavior to understand stakeholder adoption, and the Integrated Building Design framework to optimize technical and social dimensions of the retrofit. Expected findings include a quantified baseline energy use intensity (EUI) of approximately 210 kWh/m²·yr for the mall, with peak cooling demand contributing 62% of annual HVAC energy. The retrofit package is anticipated to yield a 28–40% reduction in site electricity use, a payback period ranging from 6 to 9 years depending on energy price scenarios, and a projected 20–26% improvement in thermal comfort satisfaction among staff and tenants. It is also expected that the optimized façade will achieve a measurable reduction in peak cooling load, lower solar heat gain coefficients, and enhanced daylighting performance without compromising interior aesthetics. The study will identify operational strategies, such as adaptive shading schedules and lighting controls, that maximize realized savings. The study contributes to knowledge by presenting a detailed, context-sensitive methodology for evaluating and implementing sustainable façade retrofits in tropical-humid retail environments, bridging technical performance with socio-economic viability. It advances practice by delivering a replicable framework for mid-size shopping centers, including data collection templates, modeling workflows, and MCDA criteria tailored to regional energy tariffs and occupant expectations. The main conclusion is that an integrated façade retrofit, when coupled with intelligent control strategies and stakeholder engagement, can deliver significant energy savings and comfort improvements with acceptable lifecycle costs. Recommendations include adopting modular, upgrade-ready façade components, implementing continuous commissioning protocols, and expanding the MCDA to incorporate resilience and maintenance risk considerations for long-term performance.