Urban heat is intensifying across hot-arid cities, where the vegetation-based cooling strategies that work in humid climates are constrained by water scarcity. This paper asks whether traditional building morphology can substitute for green infrastructure as a passive cooling mechanism, using Jodhpur’s historic core as a case. We combine three evidence strands: Landsat-derived land surface temperature (LST) to map urban-scale heat patterns, architectural documentation of compact plans, courtyards, and massive envelopes, and in-situ sensor monitoring of indoor conditions in two traditional houses. Historic-core surface temperatures average 0.63 °C cooler than the modern expansion (n = 8000 pixels), and built-up intensity (NDBI) explains substantially more of this variance than vegetation cover (NDVI)—consistent with the weak evapotranspiration effect expected in a water-scarce climate. At the building scale, traditional stone walls (U = 0.92 W·m−2·K−1) are associated with an average indoor cooling of 3.4 °C relative to outdoor peaks, while courtyard-centred daylight distribution (300–2500 lux in active zones vs. <250 lux in inner rooms) shows how these houses balance illumination against heat gain. We interpret these results as evidence that traditional morphology functions as passive thermal infrastructure at the building scale. Whether and how this aggregates into a city-scale cooling benefit remains a hypothesis that we outline conceptually but do not test directly; we flag this distinction throughout the paper rather than treat it as demonstrated. We propose specific edits to India’s ECBC and ICAP frameworks that would credit morphology-based design rather than only mechanical efficiency.




