Green roof benefits explored

Installing a green roof can dramatically reduce energy use and costs - as well as supporting biodiversity, reducing flooding and combating climate change.

That was the message for delegates at an afternoon seminar organised by CIRIA, the Construction Industry Research and Information Association.

Firms that have installed green roofs have reported a 25% reduction in energy use in the floor directly under the roofs, and reduced usage at a lower percentage in other floors.

Dusty Gedge, co-founder of, told delegates that City Hall in Chicago is one of many buildings that has found air conditioning is now largely unnecessary.

He said: “It takes until about 5pm for the floor under that roof to heat up so it doesn’t have to have air conditioning because at 5pm most people go home.”

But Mr Gedge argued that more consideration of biodiversity has to be given to green roofs, as many are created for aesthetic effect.

Steve Wilson, technical director of the Environmental Protection Group (EPG), told delegates green roofs can play a large part in creating sustainable urban drainage systems (SUDS).

He said: “Green roofs can help meet all the requirements of SUDS. It will not necessarily do it on its own, but green roofs can be a very important part of an overall sustainable drainage scheme.”

Andrew Jones, strategy manager or biodiversity at the Greater London Authority, said London has a policy on green roofs as part of the London Plan, but this is not the case elsewhere in the UK – a situation which is preventing more green roof development.

He said: “A barrier that still exists at a national level is there is no national policy framework that encourages the installation of living roofs and walls. There’s not many common standards that exist.”

Kate Martin

Action inspires action. Stay ahead of the curve with sustainability and energy newsletters from edie