One Canada Square the recycling of waste heat to cool and warm the building. Aggregates used in the office build were from predominantly recycled sources, part of a strategy to integrate sustainable products and materials throughout the site, delivering both affordable and sustainable environmentally friendly features to the building. One Canada Square energy performance has improved by decreasing 30% from 2007 to 2016 by initiatives such as installing LEDs and upgrading HVAC and water services. The ground floor, foyer area and basement levels of One Canada Square are open to the general public, having an underground retail area and a transport interchange from
Citigroup Centre, London to the owners. The east facing side of 25 Canada Square up to level 40 is configured for use by tenants. 33 Canada Square, or Citigroup Centre 1, is the smaller of the two buildings in the complex, designed by Norman Foster and completed in 1999, two years before its neighbour. At tall, the building is made up of eighteen floors, all of which are adjoined to their equivalent floors in 25 Canada Square. The building is owned by Citigroup, and was built before the completion of the Jubilee line extension in late 1999. In addition to main entrances from