Quantifying the impacts of green roof design factors on microclimate regulation: A case study in Washington, D.C.

This study explores and quantifies the impacts of green roofs (GR) design factors on microclimate regulation. Against rapid urbanization and intensifying climate changes, green infrastructure has received increasing attention due to its contribution to dealing with the urban heat islands effect (UHIE) and increasing urban sustainability. GR is one example of green infrastructure and is widely used in cities. However, its microclimate regulation benefits have not been thoroughly explored and require more exploration. There are insufficient studies on quantifying GR design factors impacts on microclimate regulation. Meanwhile, little research has explored the impact of regulating microclimate when accessibility is considered as a design factor. Using a GR in Washington, D.C., as a case study, this study models 14 roof scenarios with several common GR design factors, generates their simulated microclimate patterns, and quantifies each design factors impact based on statistical analyses. Results present quantitative data on how studied design factors change microclimate patterns and find that accessibility does affect some microclimate aspects but only to a limited rate. This study provides suggestions and insights to optimize GR design guidelines. Overall, this study contributes to the refinement of GR research, promotes better GR design, and responds to urbanization and climate issues.