Gardening is not the only productive option your roof can be used for. Iranian company BMDesign Studios has come up with a new roof design to harvest rainwater and aid in the natural cooling process. The company designed the concave roof—a double-layered, bowl-shaped system—to collect water in harsh and arid environments.

The Tehran-based company devised the new concept while drawing a proposal for a school in Kerman province. The design includes 923 meters² of concave roof area, which can capture 28 meters³ of water. The collected water can be connected to catchment systems, placed between school buildings. Aside from collecting water, the design provides extra shade to the ground level.

BMDesign Studio Roof (Top View)

Courtesy of BMDesign Studios

The architects told ArchDaily that the bowl-shaped roofs “help [make] even the smallest quantities of rain [flow down] the roof and eventually coalesce into bigger drops, just right for harvesting before they evaporate.” The designers continued the conversation on Dezeen: “The outer shell provides additional shade for the domed roof while letting the air freely move and cool both roofs off,” while the inner shell “is slightly domed, as only a section of a domed roof receives solar radiation directly at any time.”

The smart design will offer a modern alternative to traditional damns, which release roughly 1 gigaton of carbon dioxide a year, around 1.3% of all greenhouse gases produced by humans. Scientists also highlight that dams are a source of methane, a greenhouse gas that is 34 times more potent than carbon dioxide.