Housing: Roof Gardens Lord Dykes asked Her Majesty's Government: What steps they will take to encourage growth in the number of commercial and domestic roof gardens in the United Kingdom over the next five years. [HL2632] The Minister of State, Department for Environment, Food and Rural Affairs (Lord Rooker) The Government are committed to moving towards more sustainable low-carbon non-residential buildings which are more energy efficient, and we will continue to raise building standards to help achieve this. Defra, along with other government departments, has been promoting green roofs as part of wider sustainable construction and will continue their active promotion.