FIELD ASSESSMENT OF THERMAL CONDITIONS AND PASSIVE COOLING FEATURES IN SELECTED RESIDENTIAL HOUSING ESTATES IN YOLA, NIGERIA

This paper reports a field assessment of indoor thermal conditions and passive-cooling features in selected residential housing estates in Yola, Adamawa State, Nigeria. Four housing estates were purposively selected and five dwellings were assessed in each estate. Fieldwork was conducted between March and May 2026 and comprised an architectural audit of 20 dwellings, spot indoor dry-bulb temperature observations at 60 room-level monitoring points, and an occupant survey involving 60 respondents. The assessment documented orientation, window-to-wall ratio (WWR), opening configuration, cross-ventilation, roof and ceiling characteristics, shading, building separation and vegetation. The overall observed indoor dry-bulb temperature was 27.42°C (SD = 1.38°C; range = 25.10–29.90°C). Estate-level means varied only from 27.31°C to 27.53°C. However, the observations cannot be interpreted as validated measurements of passive-envelope performance. Approximately 45% of respondents reported air-conditioning use and 60% reported reactive curtain or blind use. Monitoring consisted of spot observations rather than continuous seasonal logging, while relative humidity, mean radiant temperature and air velocity were not systematically measured. In addition, logger calibration offsets were substantial, with a mean offset of 
0.42°C (SD = 2.15°C) and a range of −4.70°C to +4.70°C. Formal adaptive comfort compliance and causal inferential analyses were therefore not retained. The contribution of the study is instead a transparent descriptive baseline of existing housing characteristics and measured indoor temperatures, together with variables suitable for subsequent controlled monitoring and calibrated dynamic simulation.