Green and living roofs
A green or living roof is partially or completely covered with vegetation and a growing medium - for example soil - planted over a waterproofing membrane. It may also include additional layers such as a root barrier and drainage systems. It can be on a flat or a sloping roof.
Intensive green roofs have relatively deep substrates and can support a wide range of plant types, even trees. They are usually heavy and require specific support.
Extensive green roofs have lightweight layers of free-draining material (2 – 10 cm deep) that support low-growing, tough drought-resistant plants, for example sedums. They require little or no additional structural support and require very little maintenance. They can be designed into new buildings, or ‘retro-fitted’ onto existing buildings.
The benefits of green or living roofs
Energy Conservation - Improving thermal performance and insulation – keeping buildings warmer during the winter and cooler during the summer - cutting fuel and carbon costs of central heating and air conditioning.
Surface Water Run-off - Reducing run-off from roofs (by at least 50% annually), which can be particularly important at times of high rainfall – helping to reduce the likelihood of flooding and the need for complex storm water drainage systems.
Biodiversity - Providing habitat for a number of species, from skylarks to rare invertebrates, depending on the exact design of the roof.
Roof replacement - Protecting the roof waterproofing membrane from climatic extremes, Ultra Violet light and mechanical damage, and in so doing almost doubling the roof's life expectancy.
Quality of Life - Contributing to a greener urban environment and better quality of life. Providing both visually and physically accessible green space.
Noise - Working as a sound insulation barrier.
Positive Image - Acting as the symbol of an organisation or individual’s commitment to sustainability in a very public wa,y and providing a very positive and distinctive image to a building or development.
Creating a green or living roof in Cotswold District
We encourage residents and developers to create green or living roofs for many sorts of buildings, from garden sheds to major retail outlets.
- To save energy, which is important in acting to slow down climate change.
- To help prevent flooding, which is a key issue within the District.
- To enhance the biodiversity of the area.
- To enable buildings to enhance, rather than detract from the natural landscape of the District.
- To complement the important traditional buildings of our towns and villages.
Regulations and legislation
Building Regulations - There are no specific Building Regulations that apply to green and living roofs; however there may be regulations relating to load-bearing, fire prevention, surface water disposal etc.
Historic Buildings - If your building is listed, you may need to obtain Listed Building consent to install a green roof. It is unlikely that permission would be granted if you are planning to replace a traditional stone roof with a green roof; however if you are replacing a new roof on a newer part of the building, for example a 1960s extension, it is much more likely that permission would be granted.
Conservation Area - If your property is in a Conservation Area you may need consent if your building is covered by an Article 4(2) notice.
Construction standards - There are no specific standards for green roofing in the UK.
Planning policies - There are currently no specific policies in the Cotswold District Local Plan to encourage the construction or retro-fitting of green and living roofs.