• This article is part of the following channel(s)

Concave Roof provides water and free cooling

People in arid climates often struggle with two problems. The first one is the heat, and the second a shortage of water. Iran-based BMDesign Studios has come up with a new roof design for a primary school in Jiroft, Iran. The roof, called Concave Roof, is shaped like a huge bowl, which catches rainwater to drink and simultaneously provides cooling for the house.

Rain is scarce in countries like Iran, while the amount of evaporation is high, which means every drop of water is important. The double-layered roof system catches the water, even the smallest quantities, that flows down the roof, where they can be collected.

The outer shell of the roof system not only collects rainwater, but it also provides additional shading, as only a section of the roof under the bowl is hit with direct sunlight. The bowl allows air to move freely between it and the inner shell, acting as a cooling mechanism for both roofs.

Reservoirs connecting to the collection systems will be placed between building walls. Thanks to the heat storage capacity of water, the heat from the walls will be absorbed by the water, allowing for further control of temperature fluctuation of indoor spaces. This means less energy has to be used for air conditioning, which makes it a sustainable solution.

At a school with 923 square meters (9,935 square feet) of concave roof area, it is expected that 28 cubic meters (7,396 gallons) of water could be collected, with an efficiency of about 60 percent. Further research for the system will focus on maximising this efficiency.

Recessed windows and doors, and a sunken courtyard would also help control heat build up in the classrooms, offices and library. Date palms planted around the building would contribute further shade, as well as a source of food. The overall site design also includes a series of “wind towers” that will funnel in fresh air into the buildings, inspired by traditional Persian architectural elements to create natural ventilation in buildings called windcatchers.

Photos: BMDesign Studios (via Archdaily)