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.

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.

In various times, places, and cultures, the “green” roof was the norm. People lived in earthen homes that were sometimes dug out of hillsides or creek banks, and the native grasses and wildflowers grew naturally on top. Other homes had sod or thatched grass roofs. Modern people are discovering the merits of this kind of roofing. If you are planning to install a green roof, here are some things to consider and keep in mind.

1. Types of Green Roofs

Before you begin, you need to determine what kind of green roof you want. Here are some of the various types.

* Extensive – Despite the name, extensive green roofs require less maintenance than the other two types, we know it’s really counterintuitive, but that’s the way it is. Extensive roofs are nearly self-sufficient, and require maybe an annual weeding or fertilizing but that’s about it. Another plus is that you’ll find extensive green roofs are not as heavy as other green roofs, because they require less soil. If an extensive green roof is going to be covered with moss, a thin layer of growing medium such as rockwool is all that is necessary, pretty cool, huh?

* Semi-Intensive – These green roofs require more intensive maintenance – hence the name (sure that makes sense, right?). Some things to remember about semi-intensive roofs is that they require regular watering, sometimes in the form of irrigation, and they also require regular weeding and fertilizing. The upside is that semi-intensive roofs do offer more variety than extensive green roofs. Shrubs, perennials, and herbs can be grown on a semi-intensive roof. If you have easy roof access growing herbs on your roof can be a really great use of space and make for a fragrent and useful roof as well.

* Intensive – This high-maintenance green roofing option offers the most variety of design and flora. With this roof people often include garden paths, rock formations, fountains, and other elaborate additions as part of an intensive green roof. Large, flat-topped buildings can even have playgrounds and park-like settings as part of their green roof.

Don’t let the high-maintenance scare you. High-maintenance is not necessarily bad. If you are the kind of person who likes to spend time in a garden – and maybe you don’t have the land to have a regular garden – then an intensive green roof could be a good investment for you.

2. A Weighty Issue

Soil and sod are heavy. Before you get too far into your green roofing project, take the time an make the investment to have a professional determine the strength and weight-bearing capability of your walls. This is especially important if you are installing the green roof over your existing roof.

3. Choose Your Plants

Think about what kinds of plants you want on your green roof. If you want to provide a sanctuary for wildlife such as bees, hummingbirds and butterflies, then plant flowering species. If you are concerned about the surrounding eco-systems and habitats, consider native plantings for your green roof.