Two extensive green roof modules were constructed; one designed with a 100 mm mineral-based substrate (i.e., blended according to the German Forschungsgesellschaft Landschaftsentiwicklung Landschaftsbau – FLL) with 6.7% organic matter (GR-FLL) and the other with a 100 mm biologically derived and high-organic substrate with 25.6% organic matter (GR-organic). The green roof modules were equipped with 32 mm drainage layers (GR₃₂, Green Innovations, Pickering, Ontario, Canada) and were covered by pre-grown sedum plants (Bioroof Ltd, Ontario, Canada), as shown in Figure 1(a). The storage capacity of each GR₃₂ unit is approximately 2.67 L. Two extensive blue-green roof modules were constructed; one designed with a 50 mm mineral-based substrate (BGR-FLL) and the other with a 50 mm biologically derived substrate layer (BGR-organic). Both blue-green modules were covered with pre-grown sedum plants (Bioroof Systems Inc., Ontario, Canada) after being equipped with 85 mm Permavoid storage and capillary irrigation systems (PV₈₅, ABT Inc., NC, United States), as shown in Figure 1(b). The storage was restricted to 55 mm through custom-made weirs considering the load restrictions on the plywood modules and the drought-tolerance nature of sedum. Each PV₈₅ was equipped with capillary cones and mats to provide passive irrigation using the stored water. The storage capacity of each PV₈₅ (after ponding restriction) is 12.8 L. The physical properties of the two substrate types used in green and blue-green modules are shown in Table 2. Two check dam blue roof modules were constructed: one with 2.4 mm orifices (BR-2.4) and the other with 4.8 mm orifices (BR-4.8). The orifices were drilled in three PVC dams around 1 cm above the roof membrane to promote some retention through evaporation and were distributed equally over each module following the installation of a waterproof membrane and a white reflective PVC liner, as shown in Figure 1(c). The white reflective PVC liners were installed to mimic the functionality typically found in cool roofs.