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Green roofs perform a vital role in helping cities adapt to the effects of climate change by reducing the need for artificial cooling in hot weather and reducing rainwater run-off, as well as providing a range of habitats for wildlife. However, green roofs can only provide these environmental benefits if they are properly designed and installed. NFRC has a growing number of trained green roof installers and manufacturers.

What is a green roof?

A living or green roof is a roof, deck or other structure onto which vegetation is intentionally grown or habitats for wildlife are established.

Types of green roof

Traditionally there have been three broad classifications for green roofs - extensive, semi-intensive and intensive. However, whilst biodiverse roofs share many of the characteristics of an extensive roof, their increased specification merits a distinctly separate category.

GRO Semi-intensive ECO Green Roofs - Richmond Park GC
GRO City Roofs - an intensive rooftop car park in Birmingham  (1)

Semi-Intensive Green Roof

Can include characteristics of both Extensive and Biodiverse roofs. Typically requiring a deeper level of substrate, a wider range of plants can be included such as shrubs and woody plants. Irrigation and maintenance requirements are dependent on the plants chosen.

Intensive Green Roof

Often referred to as a roof garden that provide similar benefits to a small parks or domestic garden. Designed predominately for recreational use, intensive roofs often require regular maintenance and irrigation.

Axter Ltd Centenary Quay
GRO City Roofs - Extensive Sedum Roof

​Biodiverse Green Roof

Is similar in composition to an extensive roof, but is designed specifically to create a habitat that will attract a particular plant species, insects and birds, by replicating or creating a habitat. This type includes a brown roof, which is a low-vegetated version. The growing medium is purposely-selected to allow plant species to inhabit the roof over time.

Extensive Green Roof

Serve as an ecological covering that provides society with environmental benefits and the building owner with life cycle cost benefits.

A lightweight, low-maintenance roof system, typically with sedums or other hardy plant species planted into a substrate/growing medium that is low in nutrients. Irrigation is not normally required once the green roof has established.

GRO logo

NFRC provides the secretariat for The Green Roof Organisation (GRO), which is the independent UK body representing the industry trade associations, manufacturers and key players within the green roofing sector. GRO sets out to promote the green roof concept provide suitable guidelines to both manufacturers and installers and to recognise and promote correctly trained green roofing companies.

In February 2011 GRO produced the first edition of the Green Roof Code for the UK. The code, which was the result of technical cooperation across the UK green roof industry, was intended to be recognised as the code of best practice and guide behaviour relating to green roof design, specification, installation and maintenance. In October 2014, the latest edition of the Code was published.

Click on the image below, to download a free copy of the GRO Code:

The code will help anyone who is designing, specifying, installing or maintaining a green roof.

GRO Code 2014 Publication

Click on the image below, to download a free copy of the GRO Fire Risk Guidance:

This guidance document has been produce in respect of fire risk and the spread of fire.

GRO Fire Risk Guidance April 2018-Cover