The first time he saw Grodan’s stone wool in action, it was a real eureka moment for Richard Sabin, co-founder and director of Biotecture. Since then, Grodan’s growing media have become a fundamental factor in the success of the UK’s leading living wall company, both in its dedicated nursery and in its patented BioPanels. “Working with Grodan gives us the reassurance we need to be able to give the necessary reassurances to our customers,” says Richard.
When civil engineer Richard Sabin met a sustainable landscape designer while working on a project to enhance a building for the London School of Economics in London, he discovered that they shared similar concerns about the misuse of the Earth’s natural materials. “We decided to set up a company together, aimed at transforming urban architecture by increasing the number of plants on and around buildings for the well-being of people, planet and business. And Biotecture – an amalgamation of the words ‘biological architecture’ – was born in July 2007,” recalls Richard.
“We saw huge potential in vertical landscaping, but we immediately faced a challenge in terms of finding the right growing media for that. Soil would be too heavy and get too saturated, not leaving enough airspace for the roots. We considered lightweight expanded clay aggregate – also known as LECA – as an alternative, but realized that it was too loose to hold up vertically,” he continues. “Then one day, we read about Grodan in an interesting article about Scandinavian roof gardens, so we reached out and arranged a demo at our offices. When the Grodan representative poured a bottle of water on the strip of stone wool he was holding and it retained it all, we instantly knew that it was the right solution for us.”
Grodan ticks all the boxes
That strip of stone wool was PP100, a little-used Grodan product that had been specifically developed for use on roofs. “It is almost four times as dense as most single-use stone wool. This means that it has sufficient inherent structural strength and dimensional stability to be incorporated into our panels as a fundamental engineering product,” explains Richard. “This ensures that our customers can depend on a robust, compliant and fully validated living plant system that is suitable for use on the outside of buildings.”
“Secondly, stone wool is chemically inert, which enables us to provide the optimal cocktail of nutrients for the plants. Another benefit of it being inert is that, if we do suffer with any pests or diseases, they are always in the plants or roots rather than in the stone wool, so we can treat them, flush them out and still reuse the Grodan growing medium,” he adds. “And thirdly, even when stone wool is fully saturated, it still provides enough airspace for roots to exist. As a result, we’re able to create a resilient growing space to permanently support robust, thriving plants outside of buildings, despite living walls being a technically, horticulturally and hydraulically challenging environment.”
Recently completed living walls at the McArthurGlen Paris-Giverny Designer Outlet