Green Block

A maintenance-free, 100% recyclable modular building material permeated with native species

Green Block Fleet Street

Green Block London


London, New York, Honolulu




In 2017, London Mayor Sadiq Khan declared a bold challenge for the people: transform the capital into the world’s first National Park City, by designating 50% of its footprint to green spaces. Inspired by the idea, and always innovating to ensure the resilience and sustainability of the planet and its projects, WATG issued an internal challenge of its own: how can landscape architects claw back space from the roads and reclaim them for the people?

The solution was Green Block: a maintenance-free, 100% recyclable modular building material permeated with native species that can, quite literally, be applied anywhere – vertically or horizontally, over existing roads and carparks, and on the sides of buildings, lamp posts, bollards, and more. Ensuring flexibility and global adaptability, one of the key features of Green Block is self-contained irrigation and root barriers, which allows expansive concrete or tarmacked spaces to be transformed into green spaces instantly and with no impact on existing infrastructure.

In addition to increasing the visual appeal of cities, Green Block has the potential to transform the health and wellbeing of not only a city’s inhabitants, but the planet more broadly, by serving as a natural filtering system for pollutants, absorbing water in flood-prone areas, creating habitats for pollinators, and improving peoples’ mental wellbeing by providing access to green environments where one can stop to smell the roses, so to speak.

The London concept alone generated so much interest – over 1.4m views on Twitter – that it inspired additional thinking to roll out in New York City (2020) and Honolulu (2021).

Green Block is currently being prototyped, with the concept widely endorsed by esteemed organisations including National Parks Research and London Wildlife Trust, and millions of citizens.