Blue roofs are designed primarily for stormwater management. They temporarily store rainwater on the roof surface, controlling the flow of runoff and reducing the risk of flooding in urban areas. These systems often work alongside Sustainable Drainage Systems (SuDS) and help to alleviate pressure on city drainage infrastructure by slowing down the release of water during heavy rainfall.

Green roofs are rooftops covered with vegetation and soil (or a growing medium). They deliver a wide range of environmental benefits, including: