Assessing Passive Cooling Potential in Urban Housing Through School-Scale Retrofitting

Thesis Abstract

Urban housing intermittently suffers from high thermal loads during hot seasons, with low-income neighborhoods disproportionately exposed due to building form, materials, and limited access to cooling resources. This study addresses the problem of urban heat exposure and rising energy demand by evaluating the passive cooling potential achievable through school-scale retrofitting implemented in surrounding residential blocks. The aim is to quantify how school-based retrofit strategies can influence neighborhood thermal comfort, energy use, and occupant well-being. Specific objectives are (1) to characterize pre-retrofit thermal performance of 20 representative affordable urban housing units within five school-adjacent precincts; (2) to design and implement five retrofit packages—envelope insulation, shading and façade reflashing, natural ventilation optimization, thermal mass enhancement, and micro-cooling courtyards—on pilot school buildings and model their transboundary effects on adjacent housing; (3) to measure post-retrofit changes in indoor and outdoor temperatures, humidity, and operative temperature; (4) to assess changes in household energy consumption for cooling using utility data and sub-metering; (5) to evaluate occupant perceived comfort, behavior, and acceptance through survey and interview data; and (6) to develop a scalable framework for evaluating passive cooling potential in urban housing via school-scale retrofitting. The study adopts a mixed-methods research design underpinned by the Bioclimatic Comfort Theory and the Passive House-inspired principles of low-energy envelopes. The population comprises three tiers (i) dwelling units within 500 meters of five retrofit-prone schools in a major metropolitan area, (ii) school buildings undergoing retrofits, and (iii) local residents in the adjacent blocks. A stratified random sample of 40 housing units is selected, complemented by 5 school retrofit cases and 60 resident interviews. Data collection instruments include calibrated data-logging sensors for temperature, relative humidity, and globe temperature placed in living rooms and façades, industry-standard energy meters for electricity use, a climate data station for neighborhood conditions, and structured questionnaires alongside semi-structured interviews. Validation of instruments follows established protocols, with a pilot test (n=8) and Cronbach’s alpha checks for survey scales. Analytical approaches combine quantitative and qualitative techniques multivariate regression analysis and ANOVA will identify statistically significant changes in thermal metrics and energy use pre- and post-retrofit; time-series analysis and difference-in-differences methods will isolate retrofit effects from seasonal variation; thermal comfort indices (PMV/PPD) will be computed to quantify occupant comfort shifts; and a discrete choice model will explore occupancy behavior responses. Micro-simulation using ENVI-met will model neighborhood-scale microclimate interactions, while a lifecycle and cost-benefit analysis will appraise economic viability. Qualitative data will be analyzed through thematic analysis, triangulated with quantitative findings to interpret perceived comfort, behavioral adaptation, and acceptance of retrofit measures. Expected findings include measurable reductions in indoor operative temperatures by 1.5–2.5°C during peak heat periods, improvements in outdoor microclimates with cooler street-level temperatures by up to 0.8°C, and a 12–18% reduction in cooling electricity demand in adjacent dwellings. The study anticipates that envelope improvements, combined with optimized natural ventilation and shaded façades, will yield synergistic effects, with occupant comfort indices moving from marginal to acceptable ranges in a majority of cases. The research will contribute to knowledge by demonstrating a replicable, low-cost, school-centered retrofit model that creates spillover thermal benefits for nearby housing, thereby informing urban design policy, school facility investment strategies, and neighborhood resilience plans in heat-stressed cities. The study’s main conclusion is that school-scale retrofitting can be an effective catalyst for improving urban housing thermal performance and reducing cooling energy demand when integrated with neighborhood-aware planning and occupant engagement. Recommendations include prioritizing retrofits that maximize shading, ventilation, and thermal mass, establishing governance mechanisms for cross-institutional investment, developing guidelines for monitoring and replicability in other urban contexts, and promoting community education programs to sustain behavioral adaptations that support passive cooling outcomes.