b'BLUE-GREEN ROOF SYSTEMS EXPERIMENTAL STUDIES ON BLUE-GREEN ROOF SYSTEMS FOR THE MARINE CLIMATEOF BRITISH COLUMBIABy Rodrigo Mora, P.Eng., PhD, Building Science Graduate Program, BCITT he majority of residentialblue-green (BGR)were built andFigure 2 shows the experimental setup homes have wood as theinstrumented in Vancouver (Figure 1).and instrumentation of the BGR. In the decking component as part ofEach platform measures 2 m by 2 m.first two phases, the base drain remained the roof assembly. The use ofThe vegetative roofs are extensive withclosed. Therefore, the BGR relied only wood as the decking compo- local succulent vegetation.on an 80-mm-high overflow drain. nent in commercial roofs can be attractive due to its easy instal-lation and cost effectiveness. In North America, the market share of deck wood varies and mainly depends on the geographical location, with dominance in the west coast compared to the rest of the country.Blue-green roof (BGR) systems are green-roofs (GR) with a rainwater management layer, called the glue layer (BL) under its soil substrate that integrates a weather-responsive runoff control mechanism. The BL is a cavity that acts like a water buffer to help manage the rain year-round. In rainy seasons, the BL detains rainwater and releases it at a controlled rate to help attenuate storm runoff during persis- FIGURE 1: CROSS-SECTION OF THE ROOFS MONITORED.tent rain events. In dry seasons, the BL allows rainwater to be naturally drawn by the plants by capillarity, thus main-taining the roofs hydrated and cool, minimizing the need for sprinkler-based irrigation and mitigating the fire risk on the roof. The first part of this article reports on results from the initial phases of the study, which started in 2019. The second part introduces work on the current phase and outlines thefuture work. PHASES 1 AND 2EXPERIMENTAL SETUPFour roof platformsconven-tional (CR), green (GR), blue (BR),FIGURE 2: INSTRUMENTATION OF THE BGR.FALL/WINTER2025 17'