This green roof saves energy, cools, stores water and enhances biodiversity

Green roofs are nothing new, but the Brabant company ROEF is taking a different approach. With one roof, it solves multiple problems, such as heat stress and the loss of biodiversity. "We quickly came to the conclusion that it was a brilliant idea."

The start-up was founded two years ago from a family business, says Janneke de Cort. "Knaapen, it's called. It has been around since 1652 and is the second oldest family business in the Netherlands. It has always gone from father to son. Once it was a painting company, now it is a renovation company. We renovate about 500 roofs a year and thought: what more can we do with those roofs than just laying solar panels? In that capacity, we started thinking about what is possible with the roof landscape in the Netherlands. We quickly came up with the themes of climate adaptation, biodiversity and heat stress."

The idea was put into practice in the company's parking lot. "We built a huge full-size roof and quickly came to the conclusion that it was a brilliant idea. We wanted to realize it not only for Knaapen's customers, but for a much wider audience. After all, all of the Netherlands needs to become more sustainable. Around the concept we created a separate start-up. That became ROEF."

The system is intended for pitched roofs. "For flat roofs, there are already a lot of green roof systems. We developed ROEF for renovation, but now there is also a new construction version. So our system could be on all sloping roofs in the Netherlands."