Climate-Based Evaluation of Solar Radiation and Façade Shading Requirements in Ankara (1985–2060)

Abstract

Rising temperatures and changing atmospheric conditions related to climate change are expected to influence solar radiation levels and increase their relevance for facade shading performance. This study evaluated the effects of projected changes in solar radiation on building envelope and shading design. Within this scope, solar radiation trends for Ankara were analyzed using NASA-POWER observational data for the period 1985–2024 and CMIP6 (MPI-ESM1-2-HR) projections for 2040–2060. Projections under the SSP1-2.6, SSP2-4.5, and SSP5-8.5 scenarios indicate that future average annual solar radiation levels are unlikely to decline; rather, a moderate increase is projected across scenarios, with the highest absolute values occurring under SSP5-8.5. The results suggest that the façade shading ratio (L/H) may need to increase by approximately 2–4% relative to the current average value of 0.45 to maintain effective summer shading performance. The study supports climate-responsive architectural strategies by emphasizing the role of adaptive shading systems and low-transmittance glazing in future building envelope design.