Impact of the properties of a green roof substrate on its hydraulic and thermal behavior

Abstract

Green roofs integrate vegetation into infrastructures to reach benefits that minimize negative impacts of the urbanization. Green roofs use artificial soils (substrates) that have an improved performance compared to natural soils. In this work, we characterized four substrates in terms of their hydraulic and thermal properties, and performed numerical simulations of heat and fluid flow to study the effect of these properties on green roof performance. Simulation results show that the green roof behavior strongly depends on substrate properties and on moisture content prior to a rainstorm, highlighting the need of dynamic biophysical models for design/maintenance of green roofs.