“Transform buildings into cacti”: this Albi school will be equipped with an innovative system to store rainwater

“Transforming buildings into cacti to adapt to the new water cycle” is the project of the start-up Cactile, based in Albi. Seduced by this innovative idea, the town hall decided to equip the Lapérouse-Carpantier elementary school from the summer of 2025. The establishment's courtyard will be fitted with a roof with an innovative system allowing rainwater to be temporarily stored to then be reused, instead of being directly evacuated.

Concretely, metal tiles will replace terracotta ones to effectively retain rainwater. At the bottom of the roof, a pipe connected to a tank will collect it. “Thanks to gravity, the water will be immediately available and can be used to water the school playground, recently revegetated, for example,” explains Jean-Baptiste Landes, founder of Cactile. “It will also be used by the town hall’s technical service for cleaning public spaces.” There is also the possibility of using it to supply toilet water.

In total, 200 m² of roof will be redeveloped next year with a storage capacity equivalent to 7,000 liters of rainwater. This development will be financed in particular by the water agency (€33,031), the Region (€20,539) and the City of Albi (€14,893). This installation was notably one of the themes discussed during the last municipal council, on December 16. After the installation of rainwater collectors and the de-waterproofing program, the City of Albi continues to introduce measures to preserve this resource.

An idea inspired by the cactus

“The cactus has adapted to the changing climate. It is a species that has developed the capacity to collect water. It is an inspiring model,” confides Jean-Baptiste Landes. This device is ideal for urban areas where water storage is often a problem. “With the storms which are increasingly violent and the increase in floods, we have sought to limit runoff and reuse the water for drinking water,” explains Jean-Baptiste Landes.

Beyond an inventive system, these tiles can also be a way for teachers to approach the water cycle in a more original way and to address the theme of its preservation via a concrete case.