Urban Building and Infrastructure Component Assessment for Climate-Resilient Renovation: Mitigating Flood, Drought and Heat Stress in Daegu, South Korea

Cities are confronted with heat, drought, and pluvial flooding, highlighting the need for renovation strategies that enhance climate resilience while minimizing greenhouse gas emissions. This research developed an integrated assessment framework to quantify the mitigation potential of urban and building surface components using five area-based key performance indicators (KPIs): Surface Heat Contribution (SHC), Flood Mitigation Factor (FMF), Water Storage Capacity (WSC), Evaporation Volume (EVA), and Global Warming Potential (GWP). The framework combines simplified life-cycle assessment with biophysical models for heat, water storage, and evaporation, designed as an accessible complement to 3D microclimate tools. Applied to an exemplary residential area in Daegu, South Korea, the method benchmarks existing surfaces and evaluates renovation scenarios targeting heat reduction, flood mitigation, and drought resilience. Results show that surface renovation measures improve mitigation potential. The performance varies across KPIs, involving trade-offs with embodied emissions. Optimal outcomes arise from balanced hybrid strategies integrating complementary measures. Selective greening combined with low heat capacity, high-conductivity materials (e.g., metal façades) effectively reduces heat stress but increases embodied GWP and structural demands. Permeable and greened surfaces improve WSC and EVA, supporting short-term flood mitigation, yet reveal limitations under prolonged rainfall. The proposed framework supports transparent and low-carbon climate-resilient renovation decision-making.