In Îlot Fertile – or Fertile Island – 4 buildings surround a central garden. Within this small locality, you can live, work, shop and play sports. It’s built on a 1.3 hectare former industrial site, bordered by railway tracks. The buildings are made from locally sourced materials and low-carbon concrete. They are designed to minimize the need for heating and cooling. Heat pumps extract the warmth from ‘grey water’. That is, from showers, sinks and washing machines and use it to provide hot water around the site.