Construction-Period Differentiation and Spatial Dependence of Component-Level Colours in Dalian’s Historic Buildings

Present-day colours of historic buildings reflect inherited fabric and subsequent interventions. We analysed Roof, Facade, and Accent colours in 153 surviving buildings in Dalian, China, across four construction periods using CIELAB lightness (L*), CIELCh chroma (C*), Hue Family, district-adjusted models, and spatial statistics. Significant period associations occurred for Roof lightness (partial R2 = 0.125, q = 0.003), Roof chroma (0.107, q = 0.005), and Facade chroma (0.115, q = 0.003), remaining significant after grouped-function adjustment. Roof Hue Family also differed by period (Cramér’s V = 0.359, q = 0.007). At k = 4, positive global spatial dependence occurred for Roof lightness (Moran’s I = 0.188, q = 0.030) and Facade chroma (I = 0.158, q = 0.011), but not Roof chroma. Two local Facade-chroma configurations were identified. Neither global association remained significant after period and district adjustment (both q = 0.939). The findings distinguish construction-period differentiation from spatial continuity and support component-level colour documentation, comparative conservation assessment, and future monitoring.