From Warm–Humid Valleys to Cold–Arid Highlands: A Multi-Scale Simulation-Based Assessment of Tibetan Vernacular Dwellings in Northwestern Sichuan, China

Highland vernacular dwellings face multiple environmental stresses, but existing studies often examine either individual passive strategies or qualitative cultural interpretations, leaving limited evidence on how regional climate, settlement wind environments, and indoor microclimates are connected. This study investigates Tibetan vernacular dwellings in northwestern Sichuan, China, across a climatic gradient from warm–humid low altitude to dry–cool mid altitude and cold–arid high altitude. Three settlements—Zhonglu Township, Sergu Town, and Gemo Township—were examined through field surveys, settlement mapping, and measured drawings of 24 dwellings. Climate Consultant, WindNinja, GBSware CFD simulations, and Radiance daylighting analysis were integrated to assess climatic stresses, outdoor wind environments, indoor ventilation, daylighting, and envelope responses. The results show that patchy, dense, and linear settlement morphologies produce different wind-protection and ventilation performances. Building form factors decrease with altitude from 0.65 to 0.54 and 0.44, while daylighting compliance remains below 10% in all cases. The findings demonstrate the value of multi-scale simulation for diagnosing climate-responsive strategies in vernacular dwellings and provide evidence for highland settlement conservation and climate-responsive building renewal.