9:41
Al-Harbi · Thermal performance of mashrabiya façades 3.2
Chapter 3 · Passive cooling

3.2 Night-purge ventilation

Across the three monitored façades, perforation ratio was the strongest single predictor of interior surface temperature. The latticed bays ran 4.2 °C cooler on average than the glazed control during peak afternoon hours, with the deepest relief carvings providing the greatest shading benefit.

Surface temperature °C 28 32 36 00 06 12 18 24
Latticed bay Glazed control Night purge 22:00–05:00
Figure 7 — Hourly surface temperature: latticed bay vs. glazed control (14–16 June).

Night-purge ventilation amplified this effect. When the lattice apertures were left open between 22:00 and 05:00, morning interior temperatures started 2.8 °C lower than in the sealed configuration, delaying the first cooling-load peak by almost two hours.

1 Surface temperatures were logged at five-minute intervals; hourly means are shown. Instrument calibration is described in Appendix B.

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Aurora University Library · omar.f@aurora.edu · 27 Jul 2026
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9:41
Thermal performance of mashrabiya façades
Al-Harbi · Thermal performance of mashrabiya façades 3.2
Chapter 3 · Passive cooling

3.2 Night-purge ventilation

Across the three monitored façades, perforation ratio was the strongest single predictor of interior surface temperature. The latticed bays ran 4.2 °C cooler on average than the glazed control during peak afternoon hours, with the deepest relief carvings providing the greatest shading benefit.

Aurora University Library · omar.f@aurora.edu · 27 Jul 2026

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