This study investigates how thermal comfort is differentially distributed across housing tenures in high-density public housing and develops an equity-aware, measurement-calibrated simulation workflow to support design and policy decisions. Geometric models of mixed-tenure precincts are constructed in a CAD environment with explicit massing, façade apertures, and immediate shading context; hourly meteorological records provide baseline boundary conditions. Time-series indoor air temperatures are collected in occupied rooms using low-cost loggers and used to calibrate building-performance models by tuning internal gains, ventilation/infiltration, and setpoint assumptions to predefined error targets. The calibrated models produce unit- and precinct-scale outcomes (viz. discomfort hours, cooling-load intensity, peak cooling demand, and façade solar gains) and underpin scenario analyses that (i) attribute disparities between low-income rental and non-rental flats to unit size, occupancy density, orientation/exposure, and access to air-conditioning; (ii) stress-test plausible future climate trajectories; and (iii) evaluate intervention bundles ranking alternatives by reductions in discomfort hours and loads.
Preliminary in-situ logs from households using air-conditioning indicate indoor temperatures averaging ≈2.4 °C below concurrent outdoor means (≈29.5 °C), with afternoon indoor peaks of >30 °C while outdoors reach ≈32 °C, implying frequent threshold exceedances for heat-sensitive occupants. In rental flats, where >90% lack air-conditioning, indoor temperatures are expected to track or exceed outdoors, yielding substantially higher discomfort hours. An illustrative affordability analysis for single-room cooling implies 192 to 300 kWh/month, or ≈S$57–S$90/month at S$0.2994/kWh, representing a sizeable percentage of a sub-S$1,500 public-rental household income. Because future climates are likely to increase hot-day and warm-night frequencies, both discomfort hours and energy-cost burdens are expected to rise. Demonstrated with measurements from Singapore public housing, the workflow is transferable to other tropical, high-density contexts and enables comfort-per-dollar prioritization of passive and targeted measures for agencies and designers.