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Extensive Green Roofs and Irrigation

Green Team at Green Roof Technology, - Tuesday, November 04, 2014

Thank you for all the comments on the blog post:

Irrigation on Extensive Green Roofs


We believe a lot of people in North America agree with the comment that in some areas Green Roofs can't thrive without irrigation. We at Green Roof Technology don’t disagree nor agree. Allow us to bring the discussion into a fundamental perspective:  

Before you built a structure, you have to remove nature or simpler living plants that nobody watered before. Modern green roof technology is able to mimic this type of environment and allows to promote exactly this drought tolerant and hardy vegetation. With a little more understanding of this technology, it is even possible to increase the plant varieties or the plants density.

Nevertheless  the attractivity might not meet the expectations of us (humans). Our picture in mind of a roof garden is a lush green vegetation form that is created with plants that please us (humans), that are not poison or dangerous. In some areas we can achieve this goal by utilizing resources that haven’t been available at this location before the structure was built.

By using natural resources (and water is the most valuable) we start changing our environment (we take water away from somewhere – from plants somewhere) just for our own comfort. Understanding that and the value of water should create an awareness to green roof professionals or engineers to design modern green roof technology in a way that no water or super highly restricted amounts of water are utilized.

Unfortunately, the irrigation industry and most of the green roof designers grew up in an environment where resources are endless. With that said the current waste of water on green roofs is simply not acceptable to me and in these cases green roofs are an environmental nightmare - just for our pleasure (and cash) and that things look “nice and green”.   

When I drive around in neighborhoods in San Francisco in the morning, my car is being washed by all the sprinklers and nobody has a problem with that…..

Simple and efficient technology is here since many decades but not in the interest of the industry, nor “re-invented” in the US or there is a lack of common sense – maybe it is a combination of all.

Most issues I am confronted with, are a result of high tech irrigation that is just not doing what it is supposed to do, there is not the right app, poorly designed and installed, too complicated for facility people etc. or simply drains the budget of building owners over time this water costs are going up.

Let’s discuss further and email us directly:


Comment by Jure Šumi ((LinkedIn):

Interesting input Jorg. Yes, extensive roofs should be self-sufficient where they can be. But in my mind this is not possible in really arid areas like Jim is saying. With our partners in Abu Dhabi we are now investigating what plants should be used there, where top temperatures are regularly reaching 120 F in summer months (with no rain for years). If you use local plants that are surviving in desert than they are surviving only due to the fact that the roots are extremely long and go deep in to the ground to find some moisture (not possible on the roof). Limited irrigation is still needed but the roof needs design with minimised ET, so also irrigation is as low as possible.

Maybe another thing to consider. Yes or no irrigation is also a question of what someone wants from green roof. Nice look is one aspect, stormwater managment is another. We should not forget Energy efficiency. According to our investigation and perfromance tests, evaporation has big effect on energy efficiency in the summer due to cooling effect. If moisture in the green roof system drops below certain level, the cooling effect is limited. So to have best energy perfromance of the roof, than you need irrigation.


Response Jörg Breuning:

Thank you Jure.

My starting point of thoughts about irrigation on extensive green roofs goes back to a fundamental point and only a handful people make these considerations.

Humans are capable to replace nature with a manmade structure on any location on Earth and they make it suitable for people to live there. In these fundamental thoughts, I expect that humans are also able to create this lost part of nature on top of these structures.

I agree this is not always cheap and not everybody is blessed with creativity or experience. Nevertheless, it is possible and it is our responsibility if we respect nature.

The rooting depth of plants is certainly a key element - it isn’t a road block. It seems it is the preferred excuse that we don’t need to feel responsible in what we re doing and that we don’t feel guilty.

I also think it using water for cooling buildings in an open system (what any green roof is) is considered - in my world - using elementary, limited and precious resources for our convenience. In the case that producing water (in dessert states) for the wasteful irrigation of plants (to make our close environment nice) might be a problem to justify to more than 100 million people that have no access to dependable water resources.

What I am saying is, that growing plants even in areas where plants would hardly grow can be done with extremely low impact on natural, precious resources at costs that are lower in the short or long term. The current hype for green roofs can create significant drawbacks in 15 or 20 years from now to building owners if the costs of water continue to rise. Keep in mind a 20 year old green roof is not even the half of the life span of a green roof (at least that is what I know from experience).

Professionals need to start thinking long term and not for quick profit, they should disregard fancy fashions or get away from desperate LEED point collecting terms if they seriously respect nature. 

Jörg Breuning


Picture: Deep rooting plant on roof with hardly any soil and never intentially planted (in Texas at the border to Mexico).

SRWA Conference 2014

Green Team at Green Roof Technology, - Sunday, October 19, 2014

Next Generation of Sustainable Buildings


Baltimore, MD / Hershey, PA --- The Sustainable Roofing and Waterproofing Alliance (SRWA) hosted its fifth annual fall conference from October 8-11, 2013 in Hershey, PA. The event brought together a global audience of architects, roof consultants, green roof experts, building design professionals, contracting firms, and building owners. This unique program featured in-depth educational courses and hands-on demonstrations designed to inform and advocate for advanced green building practices.

Enhanced moisture control of super insulated, high performance buildings envelopes in each climate zone on Earth is the key for long-lasting, low-impact and healthy buildings. Proper solutions will maximize the payback of investments for building owners and drastically reduce the environmental footprint of building structures at the same time.

The speakers at the SWRA Conference paired common sense with decades of scientific research and developed best management practices for any building envelope application.

“With over 200 attendees from 19 countries around the world the fifth SWRA conference set a new milestone for building professionals”, said Jorg Breuning, Green Roof Service LLC – Green Roof Technology, “vegetation on top of buildings are the ultimate transition from manmade structures to the natural environment.”

Effective, economic design and maintenance principals of modern Green Roof Technology was presented and discussed by Jorg Breuning. With over 34 years of experience, Jorg Breuning demonstrated that thinking outside the box or a ridged modular grid will separate the wheat from the chaff.

The SRWA team led by Samir Ibrahim, Director of Design Services at Carlisle did a phenomenal job to make this conference happen. 

Mineral Wool on Green Roofs

Green Team at Green Roof Technology, - Sunday, September 21, 2014

 Green Roof Innovation

 Mineral Wool on Green Roofs

 Green Roof Technology Reveals Latest Study about Mineral Wool on Living

Since their first commercial production in 1871 (Georgmarienhütte, Germany), mineral wool found its way in many applications like thermal insulation and soundproofing. Mineral wool, mineral fibers are typically referred to synthetic materials like fiber glass, ceramic fibers and stone or rock wool.

Two main types of mineral wools are on the market – water repellent (Hydrophobic) and water adsorbent (Hydrophilic). For horticultural purposes, only the hydrophilic type is useful. Many patents were granted for simple Hydroponic systems or the germination of seeds with mineral wool in the early 80’s.

In modern green roof technology the first green roof systems came on the market around 1985 in Germany at a time as the German green roof industry gained tremendous momentum. As a lightweight solution with high water retention, mineral wool seemed an ideal material. The higher costs and the higher carbon footprint - comparing to lightweight aggregates – were argued with easier installation and higher water retention.

Extensive research over more than 5 years at the University of Geisenheim and on numerous buildings confirmed the high water retention properties. However, in the mid-run these tests also revealed that the performance and the health of the vegetation were far below conventional green roof systems with standardize green roof components. Mineral wool manufacturers and green roof system suppliers stepped away from the idea of using mineral wool as a growing component for green roofs.

“Today we can see a revival of mineral wools in the green roof industry,” says Jorg Breuning, CEO, Green Roof Service LLC,” in countries with hardly any green roof experience, mineral wool is getting rather popular with potentially fatal results in the mid and long-run.” 

Especially in the United States, the market is growing rapidly for mineral wools on green roofs, disregarding existing studies and without extensive long-term tests. It isn’t even proven whether certain fibers can cause health problems, leach out chemicals or whether these components can be recycled when the green roof doesn’t perform anymore.

In 2012, the lack of performance of mineral wool as a vegetation carrier resulted in a major green roof restoration at Amsterdam International Airport. 90,000 square foot of green roof – built with mineral wool - had been taken off and replaced by a standardized green roof system. At this point, this was the largest green roof restoration in the history of mineral wool on green roofs. Costs that could have been avoided.

Doing it right in the first place.

Green Roof of the Year 2014

Green Team at Green Roof Technology, - Tuesday, September 09, 2014


Green Roof of the Year 2014 – 30 Years and Counting

The second oldest Green Roof Association* in the world, FBB (Fachvereinigung für Bauwerksbegrünung), awarded a prize for Green Roof of the Year 2014 to a 30 year old Green Roof on the Allianz Insurance Company in Stuttgart, Germany. Oldest Green Roof Association DDV (Deutscher Dachgärtner Verband).

The roof is one of the first projects where Jörg Breuning, CEO at Green Roof Service LLC / Green Roof Technology was substantially involved in the realization. Allianz Insurance Company decided in 1981 to build their local headquarters in the heart of Stuttgart. At that time the office building was already a big step forward for urban development in many regards. Along with very advanced, environmentally friendly technologies it was also one of the first buildings to achieve the split between living green working space and luxurious living in downtown of a large City. 

The Green Roof is generally assembled around the building and on different levels. Most people in the offices have a view into the green spaces.  Some areas of the Green Roof are accessible for coffee breaks and, on the highest floors there is usable garden space for the Condominium owners. The top floor even offers extensive lawn areas as playgrounds for kids.

All Green Roofs together measure over 21,000 sf. This inner city oasis utilized an advanced Optigreen Green Roof Systems with fully automatic high tide and low tide irrigation system in the mineral drainage layer. The plants “decide” when they need irrigation; no drop of water is wasted or can evaporate before reaching a plant. Neither a person nor electricity is needed to operate this fully mechanical system and it leaves enough room for precipitation to fill up the water storage under the plants. This green roof represents a smart combination of Blue Roof and Green Roof as Green Roof Service LLC / Green Roof Technology is still doing it on projects today. It is a foremost and 100% accurate irrigation system far beyond most irrigation systems that are operated by sensors, electricity, Apps, tubes, pipes or other highly vulnerable and expensive equipment  we see every day on projects in North America or around the world.  

The entire depth of this highly efficient Green Roof technology is approximately 18 inch and has allowed lawn, perennials, shrubs and small trees to grow for over 30 year without replacement or  changing out the growing media. 

Green Roof Service LLC / Green Roof Technology is proud of this Award and we are pleased to offer more information about it. We offer Green Roof tours for anyone interested in this kind of technology.

This has been a landmark project for more than 3 decades and we congratulate all who are part of this Award!

*Note: Oldest Green Roof Association in the world: DDV (Deutscher Dachgärtner Verband).

Green Roof of the year Green Roof of 2014 

30 years Green Roof / 2014  

 Picture 2013 Optigreen

Green (Roof) Washing

Green Team at Green Roof Technology, - Wednesday, June 25, 2014

Baltimore (I-Newswire) June 25, 2014 - Baltimore, MD. Green Roof Service LLC - Green Roof Technology offers the most reliable and cost efficient vegetated roof solutions to meet all challenges of growing vegetation on impervious locations. With efficient and ingenious solutions Green Roof Service LLC - Green Roof Technology successfully designed and engineered multi-million square feet of green roofs across Europe and North America since 1980. Their custom tailored design is even installed on 5 Celebrity Cruise Ships sailing around the world under permanent changing climate conditions.

"I have seen everything", says Jorg Breuning CEO at Green Roof Service LLC, "but what currently happens in the United States can be devastating for an entire industry". Green Roof Service LLC receives weekly calls from clients with green roofs that are not performing as promised.
All of these underperforming green roofs are designed and installed with a lack of experience at any stage of a project or they were compromised in the engineering or construction process.

Especially permanent installed irrigation on extensive green roofs (shallow, light weight functional roof for stormwater retention) is causing increasingly problems with maintenance and operational costs. "Permanent irrigated extensive Green Roofs should not get any incentives from Government, State or Cities", suggests Jorg Breuning. "They don't reduce the stormwater issues of human settlements and they require high amounts of nutrients that can also pollute our water ways."

Irrigated extensive green roofs are often recommend with expensive pre-vegetated green roof systems that are delivered in metal or plastic boxes (often called trays or planters) and then simply placed on a rooftop. "With these solutions and additionally combined with irrigation, sustainability goes literally down the drain," warns Jorg Breuning, "this is green (roof) washing for quick bucks".

Green roof Service LLC - Green Roof Technology introduced low impact modern green roof technology to North America based on experience and common sense. Their clients truly manage environmental issues without using precious resources, at incredible low operational cost and without any risk of failure.


Green Roof Revolution in Sydney

Green Team at Green Roof Technology, - Monday, April 21, 2014

By: Samantha Yurek

On April 7th, 2014, the City of Sydney, Australia approved a Green Roofs and Walls Policy. The Policy will be carried out by the Strategic Planning and Urban Design Committee of Sydney. A three year plan, its main goal is to raise awareness of the importance of green space in urban areas as well as promote the implementation of potential green roofs and walls.

                                   Pinpointing Green Roofs in the City of Sydney

Sydney is already in the lead of the green revolution, with a total of 83 green roofs and walls throughout the city. In addition, 50-70 likely projects have been approved to construction and should be underway soon.The Green Roof Meadow at the Prince Alfred Park Pool is one of the largest in Sydney. Complete with 2,000 square meters of green space, including over 35,000 seasonal and native grasses.

                            The Green Roof Meadow at the Prince Alfred Park Pool

The city is also home to One Central Park residential towers, featuring the world's tallest vertical garden at 33 stories. These gardens consist of 190 native Australian plants as well as 160 exotic species. Although it may not be the tallest for long - Shri Lanka is now in the running with plans to build a 46 story residential building, with multiple vertical gardens, proposed to be completed by the end of 2016.

                                        One Central Park Towers in Sydney

Lucy Sharman, Sydney's Green Roofs and Walls Senior Project Officer explains, "With higher-density living and a growing population, we need to accommodate people in a healthy way and use urban space as wisely as possible." And it seems that advocating for a greener city is working. "We receive more than one development application each week for a green roof or wall," says Sharman.

                                            One Central Park Towers in Sydney

The Green Roofs and Walls Policy isn't their only attempt to create a cleaner and healthier environment. The city has been working on many movements, such as 202020. Working towards 20% more green spaces in urban places by the year 2020. 

If you're interested in, you may check out the whole Green Roofs and Walls Policy here.

MD Bill 207

Green Team at Green Roof Technology, - Monday, March 31, 2014


Today I we received an email by the USGBC requesting to oppose the MD House Bill 207. In the last decades the USGBC grew dramatically. Beside their originally great intention, LEED increased the costs of buildings super proportionally to the benefits for the environment.

In our opinion it is now necessary to naturally develop sustainable practices, solutions and technologies that can be much easier adopted and implemented by environmentally conscious people. With very simple tools (“rain tax”, higher taxes on energy, and responsibility for costs to reduce the negative environmental foot print of buildings etc.) the government now has a great opportunity giving back to builders and building owners the freedom of making their own decisions without the overwhelming pressure and costs from LEED.

Bill 207 helps to increase environmental consciousness of all American individuals and gives them back their freedom and responsibility in making their own decisions.

What is described as a setback by the USGBC is just a desperate reflex and fear of losing revenue and influence. USGBC must learn this lesson and USGBC has to prove that they are still competitive once Bill 207 passed.  

If the USGBC can’t take this as challenge they are worthless to start with.  

We support MD House Bill 207

Only Natives on Green Roofs?

Green Team at Green Roof Technology, - Monday, February 17, 2014

By: Jörg Breuning

In 1999 North America discovered that modern green roof technology is more than just an exclusive garden for a few wealthy people on top of a building. Experts understood very quickly that there are unmatched advantages of bringing back nature into locations where it was before.

With this enthusiasm, a lot of environmentalists and environmental organizations started to notice various opportunities to improve, simplify or promote themselves in many ways. Some of these ideas might sound glamorous, but the bigger picture concerning nature, is often disregarded.

In a previous blog post we reported about the ridiculous reductionist research of comparing reflective roofs with green roofs. Today we want to focus on the hype of native plants for green roofs:

Many Americans call a living organism native if these organisms have been on this continent before North America was discovered by European settlers. In their naivety, they have completely forgotten how the Natives have discovered and have lived on the land hundreds to thousands of years before.

So called Native people did the same as any organism; they expanded from their original locations to secure the species. While migrating and expanding over continents, all living organisms will change their environment accordingly. Microorganisms like bacteria or macro organisms like humans follow in the same footprints in evolution. The migration of European settlers did that as well and eventually became 'native'.

For most American people (as mentioned on Wikipedia) the opposite of native is "invasive". This discrimination is completely ignorant to the fact that something must be introduced first before it is invasive, encroaching, or just simply trespassing. 

It is even a bigger discrimination and ignorance of God's creation or evolution (whichever you prefer) when these people ( a lot of them call themselves experts) tell us that approximately 1,000 hectares of Bamboo scattered across the USA are a problem for when they call native species. However, at the same time, 1,000,000 hectares (1,000 times more) of genetically modified corn is not a problem. On top of this blatant discrimination, these 'tunnel-view' educated people (including LEED™) are pointing out that roofs are an ideal place for what they deem native plants.

Rooftops might be a stepping stone environment for plants that have been in North America for many thousands of years but when we try and set them up in a new place it is like a conversation of a narrowed down selection of species and disregarding the entire picture. It is obvious that history repeats itself - there are still existing reservations for Native Americans and we all know what effort this was, how discriminating this was and how much diversity, knowledge and inspiration we have lost. We are essentially treating native plants in the same way and that has nothing to do with environmental protection.

These so-called native plants must have a so-called native environment and require all the natural players (other living organisms) to thrive.

* Jeffersonia diphylla for example depends on ants to spread and what building owners want to have colonies of ants?

* The big family of Trifolium (stamped as a weed by nurseries) requires the stiff hair of animals to fulfill their natural calling - how many deer of bears do you want on your roof?

* Or shall we shoot all the birds that spread seeds from introduced trees?

The point of this blog is that any type of nature is better than covering the ground with impervious surface areas like asphalt, concrete of ground mounted solar factories. All our environmental issues are caused by the loss of natural environments. It is also much cheaper to protect these natural environments where they are and avoid relocation into reservations (such as rooftops). Simply by reducing footprints of man-made structures and concentrating human settlements to specific location allows these so-called natives organisms to thrive and to continue their journey of evolution.

An Upstream Battle for Green Roofs?

Green Team at Green Roof Technology, - Wednesday, January 29, 2014

By: Jörg Breuning

Every now and then we find studies comparing green roofs verses white roofs. It seems like and up-stream battle for the green roof industry against the big profits that are being made in the roofing industry with reflective water proofing membranes. All manufacturers of roofing material know that a reflective membrane will sell easier and with a higher profit than a traditional black tar roof. It is cheaper in production, and with the right crew, easier to install as well. In addition, because of the environmental benefit (discovered by LEED), the pricing can be more expensive.

Covering this membrane with a green roof should increase the profits - so we think. In reality, it isn't the case because the lack of horticultural understanding and human's natural fear of nature make it a high risk factor or even a potential lawsuit. Stockholders and risk managers for large roofing manufacturers offer green amenities (because this is good for their image), but never pressure these offers. Unfortunately, for roofing companies, protecting the revenue and profits is of higher priority over the environment and real sustainable practices.

It is no secret that selected manufactures support Universities in order to preform research on reflective membranes verses green roofs. These manufacturers tell the researchers precisely what to say and do so their reputation thrives. Since research jobs are not plenty full and Universities have the same economic pressure as roofing manufacturers, the results of this research may be questionable.

In an older selective or reductionist study at Lawrence Berkeley National Laboratory, the so-called scientist went a step further. Writing a paper, clearly motivated by manufacturers, they described their data as somewhat sparse - does that mean worthless?

We still try to understand the words that are used in this study:

"Somewhat" = to a moderate extent or by a moderate amount

"Sparse" = thinly dispersed or scattered

We at Green Roof Service LLC/Green Roof Technology don't need simplyfied research that says "maybe yes" and "maybe no" in one sentence without considerations of the entire picture. Many people in the green roof industry don't have a scientific backing, but it is a great gift that they have common sense and understand that bringing back nature to where it previously resided is way better than covering the earth under a white burial shroud.  

The bear in the stream catching the battling salmon can't extinguish the species - as long as the water is clean. If the water is polluted because of the lack of nature in our built up Cities, there won't be any salmon left and the bear will shortly become extinct as well. Responsible research and researchers can help keep our waterways and neighborhoods clean - or address a topic holisitc.

See also our blog post: 

White Roofs are Better than Green Roofs!


The Green Edge: How Commercial Property Investment in Green Infrastructure Creates Value

Green Team at Green Roof Technology, - Saturday, January 25, 2014

By: Samantha Yurek

According to the EPA, green infrastructure is simply the title given to an approach using environmentally friendly techniques to manage stormwater. This can include multiple efforts such as green roofs, permeable pavement, rain gardens or even planting more trees. It is well known that green infrastructure aids in decreasing stormwater issues, and ultimately creating a healthier environment and more livable neighborhoods. 

This past December, the Natural Resources Defense Council released a study on how investing in green infrastructure creates value for commercial properties. The environmental benefits have been obvious, but how can green infrastructure help YOU out??


Picture: First Blue Roof and Green Roof combination in the US

The NRDC explains that "Commercial properties with well-designed green infrastructure can reap the rewards of higher rents and property values, increased retail sales, energy savings, local financial incentives (such as tax credits, rebates, and stormwater fee credits), reduced life-cycle and maintenance costs, reduced flooding damage, reduced water bills, reduced crime, and improved health and job satisfaction for office employees."

If interested in reading the full article you may visit the NRDC official website.

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