asked Her Majesty's Government:

Whether they will consider additional measures by way of a Department for Environment, Food and Rural Affairs promotional effort to persuade companies and other owners of large flat-roof premises to construct energy-saving roof gardens. [HL4791]

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. A key element of maximising the energy efficiency of buildings is ensuring that they are suitably insulated. Raising building standards will act as a further driver for improving insulation and green roofs offer one possible solution for delivering better insulated buildings.

Green roofs can also be a form of source control for attenuating the run-off of surface water (ie comprising one element of SUDS (sustainable drainage systems)). Defra is promoting the use of all forms of SUDS while acknowledging that not all forms are appropriate in all circumstances and that there are currently some obstacles to their wider uptake. The most significant obstacle is that of the adoption of some drainage (conveyance) elements of public SUDS systems. Defra is intending to consult on options for the adoption and the long-term funding of maintenance of these systems later this year.

Green roofs will generally not fall into this category and will normally be the responsibility of individual building owners. Defra, along with other government departments, has been promoting green roofs and other elements of source control (such as porous paving) as part of wider sustainable construction and will continue their active promotion.