How Are Green Roofs Installed
The German FLL guidelines are followed internationally, due to the nations dominance in the market. There are no official UK standards so ensure your installer understands and follows the FLL.
Green roofs need to be installed on roofs pitched at no more than 30°.
The planting is just the tip of the iceberg underneath, a moisture-retention fleece keeps water in the soil rather than letting it pool on the membrane surface an aqua drain carries away excess water. A good membrane is nonetheless required to prevent leakage, while a vapour control layer manages the passage of internal water vapour through the roof, preventing condensation inside.
This property, under development by , will eventually have a 60 sq m green roof planted with bee friendly flowers. Green and Blue bee bricks have also been used as part of the extension, providing shelter for solitary bee breeds.
How Much Does A Green Roof Cost
The cost of a green roof varies considerably depending on the type and factors such as the depth of growing medium, selected plants, size of installation, use of irrigation, and whether they are to be accessible on inaccessible – intensive, semi-intensive, or extensive. Intensive green roofs typically require greater investment but confer the benefits of accessibility. An installed extensive green roof with root repellent/waterproof membranes may be installed for $10-$24 per square foot. While green roofs typically require a greater initial investment, it is important to keep in mind that they can extend the life of the roof membrane and reduce the heating and cooling costs of your building. Speak to a qualified Green Roof Professional about the range of costs and benefits for different green roof systems and designs.
What Drainage Does A Green Roof Need
A green roof installation consists of a number of layers, and needs to follow some basic principles. Firstly, soils can potentially have a negative impact on the waterproofing layer. Therefore it is standard practice to have a protection layer on the surface of the roof this is essentially a puncture-resistant geotextile.
I often dispense with conventional drainage layer, and instead weave dry shingle river channels across the green roof to move excess rainwater to the outlet. This approach also has the added value of giving some pattern and topography to the finished green roof.
Dusty Gedges
Although green roofs store rainwater, there needs to be adequate drainage too to enable excess water to drain off the roof. The conventional approach is to use a plastic eggshell-style drainage layer, but there are natural alternatives. A gravel layer was traditionally used on the continent, but it is heavy and increases the load on the roof. I have recently seen a cockleshell layer being used on a number of small green roofs cockles make a lightweight alternative to gravel.
In order to stop the soils washing out, a filter sheet is installed above the drainage layer. This also needs to run up the sides of all perimeters. This later lets the water move through, but holds back the fine particles of soil.
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Installation Of A Green Roof
If you are looking to install a green roof, you may wish to first install a protection board that covers your normal roof. A layer of waterproof membrane is placed on top, followed by a layer of soil and on top of that the preferred vegetation is planted.
Some roofs, called extensive roofs, have a thinner layer of soil and are best suited for plants with shallow roots such as mosses and sedum. Other roofs, called intensive roof gardens, have a deeper layer of soil or other growing medium and so can sustain hardier plants including trees with stronger roots.
The waterproof membrane is normally made from a material such as ethylene propylene diene monomer, a rubbery material similar to the lining put down when you build something like a duck pond in the garden. This layer prevents water getting in but also stops roots from the plants growing down into the roof. There is also a possibility of adding a further insulation layer that can be placed either on the roof beams or above the waterproof layer .
To effectively maintain and water your garden, a filter layer, a drainage layer and a water retention layer are placed. These various layers also help ensure that the soil is not washed away. On top of that, a mix of porous material and soil is placed which is the growing layer.
It is important that the growing medium is as light as possible but still allows plants to flourish.
Costs And Financial Benefits
A properly designed and installed extensive green-roof system can cost $108$248/m2 while an intensive green roof costs $355$2,368/m2 However, since most of the materials used to build the green roof can be salvaged, it is estimated that the cost of replacing a green roof is generally one third of the initial installation costs.
With the initial cost of installing a green roof in mind, there are many financial benefits that accompany green roofing.
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Living Roofs Are Energy
With the green plants covering your roof, living roofs offer insulation against the scorching summer heat. As a result, your house or building will remain cooler during the hot summer months, reducing your cooling costs substantially. According to a recent study, a living roof can reduce your need for air conditioning by 50%, and when it reflects in your cooling costs, you can end up saving up to 30% of your energy cost depending upon the type of living roof you choose.
What Is The Difference Between Extensive And Intensive Green Roofs
Extensive green roofs are very lightweight and require very little maintenance. They tend to have an attractive low layer of vegetation consisting of grass, moss, sedum or wildflowers. Sedum roofs are the most common choice due to their hardiness and low maintenance.
Intensive roofs on the other hand are a whole lot more complex. They are designed to support larger plants such as bushes and small trees which is why theyre often referred to as roof gardens. They normally require a layer of growing medium or soil to support the much thicker vegetation layer.
You can find out more about both intensive and extensive green roofs in our green roof construction guide.
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Maintaining Your Green Roof
Once you have installed your green roof, youll need to look after it. The great thing about green roofs is that in the main they self-regulate. This means you can enjoy their benefits pretty much as soon as theyre built, without having to spend too much time looking after them.
But there are some things youll need to do to keep them happy, healthy and thriving. Different seasons, changes in the weather and other environmental factors can all take their toll on your green roof, so some maintenance will be needed as the years go on.
To maintain your green roof, youll need to do things like:
- Manage plant encroachment
- Water your green roof when there is no rain
- Maintain your green roof membrane
- Identify common problems and solve them
Weve written a full guide on how you can look after your green roof throughout the year. Head to our green roof maintenance guide.
A Green Roof Maintenance
Maintaining your green roof is no different to maintaining your garden. Extensive green roofs are easier to maintain compared to intensive ones, but they all need weeding and cutting.
This is why it is important to ensure that there is safe and easy access to the green roof. What is more, you can choose to cover either the entire roof or just a part of it.
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Where Can I Learn More About Green Roofs
GRHC’s Education Program is the source for the most comprehensive information on green roofs and walls in North America.
For general information on green roofs and walls, please check out the rest of our website and the Living Architecture Monitor magazine. More information can also be found on some of our Members’ web sites.
Who Can Design And Install Green Roofs And Walls
A Green Roof Professional should be the professional of choice on any green roof project, and many of our GRPs are also equipped to design and install green walls. Some jurisdictions specify that a GRP be part of any green roof design team.
Because green roof systems include materials not found on conventional roofs, we recommend that you choose a qualified roofing contractor with experience in green roof installation to install the non-living components . Contractors can be found in the Green Pages Industry Directory.
You can also contact a roofing consultant, who will assess your roofing design needs, ensure quality control and recommend a suitable green roof system.
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What Are The Different Types Of Green Roofs
The two main types of green roofs are extensive and intensive green roof systems.
Each type of green roof suits a different purpose. When it comes to choosing what type of green roof that will work best for you, youll most likely need an extensive green roof as these cover most smaller, domestic projects such as green shed roofs, garages, extensions. But lets look at the differences between the two in a little more detail.
How Do Living Walls Work
Green walls are constructed much the same way actual walls are. You build a base to work from a skeletal structure and hang the plants and flowers from or within modular trays, troughs, trellises or in planters.
But they all work in largely the same way. Of course it depends on your green walls purpose in life to feed, to improve air quality or thermal performance.
But as the flora and fauna reach maturity the walls performance improves.
- Your homes ability to retain heat in winter and cool in the summer could reduce your bills.
- You can become more self-sufficient food-wise
- Noise levels are reduced
But so much of this relies on you properly caring for your wall. Trimming and weeding when appropriate, watering or ensuring the irrigation system works properly.
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Impressive Living Roof Examples In Details
Images are Courtesy of MVRDV
Images are Courtesy of MVRDV
Currently under construction, Valleys three peaks of varying heights reach up to a maximum of 100-meters at which the publicly accessible Sky-bar sits, spread out over the top two stories, offering panoramic views over Amsterdam. The building consists of 200 apartments, 7 stories of offices, three-story underground parking with 375 parking spots, and various retail and cultural facilities. From street level, a pedestrianized path, running along with retail functions, terraces, and roof gardens, leads up to the central valley-area spread across the 4th and 5th level and surrounds the central tower.
Images are Courtesy of MVRDV
A Green Roof System That Optimizes Benefits
Green roofs offer many benefits to both building owners and the communities in which theyre situated. With LiveRoof, you get an instant green roof, for optimized benefits from the day of installation.
LiveWall empowers its customers with green wall structures, protocols and plants that make living walls simple and lasting.
LiveWall sells its systems directly to owners or contractors for use on buildings around the world.
Hortech, Inc. is Michigans leading wholesale supplier of responsibly-grown ground covers, ferns, climbing vines and ornamental grasses.
Find Grown Earth Friendly Plants® at independent garden centers in Illinois, Indiana, Michigan and Wisconsin.
93% of our lives are spent indoors in biological darkness, under unhealthy, energy-draining lighting.
With a simple switch to Norb® wellness lighting products, youll experience biologically-natural lighting for better living.
We are always looking for great team members! LiveRoof is based in Nunica, Michigan. Click to see open positions with LiveRoof, LiveWall, and Hortech companies.
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Green Roofing And Religion
Transforming our religious buildings to have living roofs is a great way to model sustainability. Two examples include the United Methodist Church in Washington, D.C. and The First Unitarian Society of Madison in Madison, Wisconsin.
John Hill at UMC describes how the green roof helps with heating and cooling costs and adds a spiritual message as well: The vision that God has for this world is very different than the world were living in. And I think our job as Christians is to try to close that gap between what we say and what we believe.
The FUS building was commissioned by the famous architect, Frank Lloyd Wright, so it is a national treasure. Its living roof addresses a variety of issues, helping to dramatically reduce storm water runoff , decreasing energy use and costs and it adds picturesque beauty to the landscape.
A green roof is an example of a sustainable solution: good for the planet, society and your wallet. So what are you waiting for? Build your own green roof today.
History Of Living Walls
What makes living walls so fascinating to us is just how recently they have been popularised.
Green walls were were first developed by Stanley Hart White, a professor of landscape architecture at the University of Illinois.
In 1938, he created a patent for his vegetation-bearing architectonic structure and system, but the invention didnt really take off. So it stayed as a singular entity in his back garden.
Patrick Blanc a French botanist who specialised in tropical forest undergrowth is generally the man credited with popularising green walls.
He worked with an architect and engineer to implement the first large indoor green wall or Mur Vegetal in 1986 at the Cité des Sciences et de lIndustrie in Paris.
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Diy Planting A Living Green Roof
Green Roof, Photo courtesy Ryan Somma, Licensed under CC BY-SA 2.0.
One of the most important decisions when building a green home is choosing a roof type. Because the energy efficiency of a home often comes down to heating and cooling, it is of utmost importance that a green home has the right roof to provide insulation rather than letting valuable hot or cold air escape. In addition, a roof that requires frequent maintenance and replacing will contribute negatively to the environment by adding waste to landfills.
Heat-reflecting recycled metal roofing, recycled roof tiles, and other green roof products are all great options for energy-efficient and earth-friendly roofing. But what if your roofing choice could be all that and more? Living green roofs are not just eco-friendly and energy-saving they come with a huge abundance of benefits that other roof options simply cant compete with. And unlike other roof options, planting a living green roof is something you can DIY-install on your own!
What is a living green roof?
The General Services Administration has designed and maintained green roofs for decades, currently maintaining at least 24 green roofs in 13 cities around the country. Green roofs are defined by the GSA as vegetated roofs consisting of a waterproofing membrane, growing medium and vegetation overlying a traditional roof.
What Is A Green/ Living Roof
- 11:49 am
Did you know there is such a thing as a living roof? Thats right. Your roof can actually be alive and growing. While we do not put together these green roofs, we are quite fascinated by them. They are rare, but they are rather amazing.
So, what is a living roof?
Read on to find out.
A green roof, or a living roof, is an entire roofing system that can both benefit the earth, and better control the temperatures of the homes themselves. While we try to avoid moss or lichen growing on roofs, and therefore we do not recommend having plants growing on an average roof. However, if your roofing system is specifically designed to support plant growth, then a green roof is very possible.
Green roofs must be fully waterproof and properly built for plants to thrive. When it rains, the vegetation on the roof will soak up the water and prevent flooding and leaks. Some living roofs are designed to redirect water whereas others are designed to use the water solely for the plants themselves. Green roofs will also have a specific root repellent to protect the architecture and keep the plants properly in place. Some roofs can hold more plants per square foot whereas others are only made to hold a certain amount. Each roof is different and customized to the needs of the customer.
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What Can I Plant On A Green Roof
The best green roofs in the long term tend to be ones that a re planted and seeded. This approach allows the roof to develop and adapt to the particular circumstances on any given green roof.
There are now UK nurseries and seed companies that can supply plants for green roofs. Small plants should be used with plug balls of around 55mm. These small plugs have plants with a small leaf area, meaning theyre less susceptible to water stress and can respond better to the conditions on a green roof. Pre-grown solutions are another approach, whether sedum or wildflower blankets. For sedum blankets we would recommend at least 80mm substrate, and for wildflowers at least 150mm.
If you are going to plant a green roof, choose a wide selection of wildflowers and sedums:
- Non-native alpines and bulbs such as crocus and dwarf iris can be planted too.
- Many bulbous plants are adapted to suffer extreme cold and extreme heat.
- Muscari is a classic plant of the Turkish mountains theyre covered in snow throughout the winter and experience the Anatolian summers and as such, is a great option for green roofs.
- Another bulbous plant that is a must is chives, which are hardy and will stay in flower even in droughts.
- Autumn bulbs like cyclamen and Colchicum autumnal bring colour later in the year.
- Choose native wildflowers that benefit wildlife too, such as Vipers bugloss and birds foot trefoil.
