Why Have a “green Roof”?

What are green roofs?

Green roofs or eco-roofs are the modern versions, and have many of the benefits of the ‘sod roofs’ that have been used in Scandinavia for centuries. Green roofs have risen rapidly in popularity, particularly in Germany and the Netherlands, and now in the UK.

There are 2 types of modern green roof systems, intensive and extensive. Intensive green roof systems are generally for heavier landscape constructions on flat roofs, whereas extensive systems can be installed over any deck and contain a number of layers including vapour retarder, insulation and waterproofing membrane layers beneath the vegetation. The general idea is to firstly provide a waterproof layer on a flat roof (or angled up to 45 degrees), and then put a thin layer of living vegetation on top of this.

What is the point of a green roof?

A green roof / eco-roof / living roof as the name suggests, has a more positive environmental and energy efficient impact than a conventional roof. A green roof provides an ecologically friendly space which ‘gives back’ to its environment rather than harming or taking away from it.

Unlike ‘roof gardens’ which are traditionally for city dwellers with no ground level garden space, green roofs are not as ‘heavy’ i.e. they only have a thin layer of vegetation (sedum and mosses). Roof gardens have large amounts of soil and all manner of plants, which in turn means work and maintenance are required throughout the year. Green roofs however are virtually self-sustaining, perhaps requiring some weeding once a year, or an application of slow-release fertiliser.

There are a number of other benefits to green roofs:

Rainfall is trapped in the vegetation and released slowly, thus helping to prevent flooding.

The layer of vegetation acts as natural insulation, thus reducing your heating / energy consumption and bills.

The insulating properties of the vegetation layer also reduce any extremes of temperature inside a building i.e. the sun’s heat is absorbed during the day keeping the inside of the building cool, and this heat is retained at night keeping the building warm.

Green roofs provide a fantastic environment / micro habitat for wildlife e.g. beetles, spiders, birds, bees and butterflies.

A green roof is visually appealing and contributes to a more ‘natural’ looking environment in a built-up area.

How can you get a green roof?

Find a specialist flat roofing company in your area, and ask them for a survey and quote.