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First International Bird Airport on Intensive Green Roof

Green Team at Green Roof Technology, - Monday, February 18, 2013

 Ornithoport in Bonn

Picture: Bundeskunsthalle

Airports are plentiful in our world, but a unique concept involves creating airports specifically for birds.  An exhibition on the roof of the Art and Exhibition Hall over the summer of 2012, highlights this common area as a destination point for birds.  To aid this bird airport (ornithoport), nesting boxes and feeders were installed, as well as approach and departure structures, complete with flashing airport signals and safety announcements.  All together this presentation is not only an awesome art piece, but probably the best landing facility for birds from all around the world.  The curator of this project, Professor Res Ingold explains, "In our case, it is an artistic project with scientific backing."

Founded in 1992, the Art and Exhibition Hall of the Federal Republic of Germany has played an important role in the community of Bonn, Germany.  Designed by the architect, Gustar Peichl, the building displays various exhibitions in fields of art, archeology, cultural history, science, and technology.  Aside from exhibitions, the community center frequently hosts symposiums, conferences, performances and concerts.  One of the more attractive aspects of the building is the intensive rooftop garden, which is often site for sculpture displays.  This vegetated rooftop is a nice addition for relaxing with a fantastic view of the surrounding city.  In the summer refreshments are served at the beer garden, wildflowers brighten the landscape and the air is busy with buzzing honeybees.  Multiple honey bee colonies call this rooftop garden home.  In 2012 these little magnificent creatures produced 1,200 pounds of honey!  Accurate daily monitoring of the productivity of the honey bees is accessible online in German, French and English. 

Green Roofs on the Move

Green Team at Green Roof Technology, - Tuesday, January 29, 2013


By Jörg Breuning

Well before modern green roof technology started in Germany in the 1970s, I was already collecting Sedums in the Alps.  As a kid I liked the little ‘fir trees’ because I was able to carry them home in my stuffed Lederhosen pockets and miraculously they would survive, even after a 4-5 hours hike.  Forty years later, there is still one surviving ‘fir tree’ growing out of a terra cotta pot at my Mom’s house. The last time it was repotted was more than 20 years ago.

When I was a teenager, Professor Hans Luz, a Landscape Architect from Stuttgart, Germany, was pioneering the implementation of green roofs on buildings and parking structures.  A visionary, Luz recognized green roofs’ stormwater retention potential and their overall ability to reduce the environmental footprint of any building.  From there green roofs went viral, spreading throughout Germany and Europe.  It was not long before cities began realizing the relief green roof provided to their overloaded combined sewer systems.

By the nineties green roofs had spread all over Europe.  Pockets of green roof believers had developed in cities across Europe.  But modern green roof technology was struggling to spread beyond the borders of the EU. 

During the nineties I frequently vacationed to the United States, notably the Southwest.  Even while on vacation one part of my mind was always considering how green roofs could be introduced to the States.  I desperately tried to make presentation about green roof in the USA but associations like International Erosion Control Association were never interested.  I talked to many American landscape companies during my vacations, but they simply thought I was crazy.

In 1999 Chicago’s Mayor Delay visited Germany and saw a green roof for the first time and decided he wanted this technology on his City Hall.  Almost 30 years after green roof technologies were first developed in Germany the time was finally right for the United States.  I am proud that I brought green roof technology to this project in Chicago.  

Twenty years from now I believe green roofs will be a fundamental part of all new buildings, as important a basic building feature as windows, doors, heating and cooling, water supply, etc.  In the end it is all about reducing the footprint of a building and putting on top of a building what was once on the ground – this is just common sense.  In my opinion it is simply our responsibility that we have to diminish our impact into nature.   We can do it in many ways, but green roofs seem the most efficient.  The longer we wait the more of our current profit and wealth we have to sacrifice later.

Success also means Green Roofs must be done right the first time.  There is no need to over engineering, use irrigation, strive desperately for LEED points, embellish the aesthetic design or embrace crazy environmentalists’ ideas that want green roofs to save the entire world.

This reminds of another success story that started in Stuttgart, Germany when Gottlieb Daimler (Mercedes-Benz) invented the world’s first car.  His invention went around the globe in a very short time and is the basis of any functional economy.  From the same place, green roofs are now starting to go around the world and will be the basis of any functional urban ecology.


Green Roof Professional Celebration

Green Team at Green Roof Technology, - Monday, January 28, 2013

Thirty years ago on January 27th 1983, Jörg Breuning was one of the first people in the world to earn a green roof professional accreditation. 

Optima, now Optigrün AG, was the first green roof manufacturer to offer an in depth educational system for the installation and maintenance of their products.  In order to be eligible for the accreditation, a candidate had to have completed 3-years of apprenticeship with a certified landscaping company. 

Jörg’s green roofing career began on September 1st 1980 at Otto Arnold GmbH, one of the first landscaping companies in the world with its own green roofing division.  In 1985 he earned his national certification and horticultural technician degree – a program of work and study that required 5-years of practice in an approved landscaping company and 4 semesters of University study. 

Jörg learned green roofing from the original pioneers and visionaries of modern green roof technology.  Since those early days in Germany, Jörg has gone on to pioneer many new innovations in green roof technology, start multiple companies in both Germany and the United States, and completed multiple award-winning projects

Everyone here at Green Roof Technology would like to congratulate Jörg on his 30-years of excellence in the green roofing industry.  

Green Roof on Floating Home "Siberfisch"

Green Team at Green Roof Technology, - Monday, January 21, 2013

First Sustainable Home on the Water with a Green Roof


With the cost of living in large cities constantly rising, the search for viable alternatives is constant.

Flo Florian and Sascha Akkermann of design firm Confused-Direction and the project-developer Bernhard Urich had urban affordability in mind when they designed the Silberfisch houseboat.

The house is a thoroughly modern floating home that, instead of occupying a valuable plot of land, is anchored in a body of water. In theory, the Silberfisch would allow residents to remain in a location indefinitely or relocate on a whim. It’s an interesting concept whose acceptance by the general public might be debatable.

However, the eco-friendly principles underlying the house are universally appealing. Two of the primary “green” methods used in the house’s construction are a green roof planted with vegetation and the use of reclaimed wood wherever possible. The toilet is an Eco-Toilet which saves water recources. Additionally, the house produces zero emissions. As home prices and eco-friendliness become increasingly critical issues, Confused-Direction’s Silberfisch houseboat may become a realistic option.










Silberfisch houseboat is a floating home by Bernhard Urich and the guys from the design firm Confused-Direction Flo Florian and Sascha Akkermann. This eco-friendly project, with zero emissions, represents a balanced mix of design and maritime romance. It has been designed for the areas with big water surfaces or in cities where property costs are high house boats offer an alternative.

Visit also their home page:


Cool Roofs are not Green Roofs

Green Team at Green Roof Technology, - Thursday, January 17, 2013

By: Jörg Breuning


In Physics class we learned basics about thermodynamics and about thermodynamic equilibrium. In simple words the content of a black coffee mug “adjusts” faster to the surrounding temperature than in a white coffee mug assuming the material and material thickness of the mugs are the same.

Exposing these mugs to the sun light the black mug will convert the electronic energy (sun light) into heat faster and no light or shade cools it faster assuming the ambient temperature is lower. The physics behind converting light into heat is called radiation-less transition. White (or bright) colors reflect the (sun) light more effective than black. 

Any macroscopic or microscopic body on our earth is exposed to these physics properties including all particles in the air of which can be plentiful in polluted cities. While the sun light enters in to the earth's atmosphere, all bodies (particles in the air) receive portions of the sun's electronic energy and convert them in to heat. For example, on a high mountain we experience much more sunlight, or electronic energy, because the air is "thinner" or has less particles in which the light has to travel through. On a beach the light intention is also very high and this is caused by the reflection of the light off the the water and sand. Sunburns on the beach are of high risk because of the consistent wind, we don't experience the transition from light into heat on our skin as fast. No living organisms can reflect the light 100% effectively, but they can actively reduce the consequences (heat) by using techniques such as evapotranspiration.

Roof Surface Temperatures
(a sunny day in May, air temperature around 72ºF)

Reflective roofs can't reflect 100% of the light either, but they are good to a certain degree (see roof temps above). However while reflecting the light back in to the atmosphere, this reflected light will meet all the particles (bodies) again and substantially increase their temperature. It is well proven that less than 5% of sunlight is reflected back into space once it's in our atmosphere.

White roofs relocate the transition point of light into heat from the roof into the atmosphere or surrounding bodies (e.g. buildings). They simply don't eliminate the problem of increasing temperatures (heat island effect) caused by human settlements and they don't decrease the environmental foot print of structures. In addition, the white surface has a slow thermodynamic equilibrium. It takes a long time to to heat up in the winter (when heat is necessary) and cools down slower during summer nights.

The kingdom of plants were the only organisms over millions of year who developed a super-efficient mechanism to reduce the heat transitioned from the sun light. It is called evapotranspiration - powerful, miniature AC units powered simply by solar energy. These super little AC units are found naturally on Earth, but can be practically placed anywhere.  By using this naturally occurring phenomenon and installing green roofs, the outcome will go further beyond any man-made machine or material.

In many countries where insulation requirements are more intense than in North America, it is questionable whether reflecting roof material makes sense to start with. From a global environmental perspective and understanding the basic science of physics, reflective roofs are just relocating the heat issue caused by human development. It is similar to building a chimney higher at a coal power plant so not to pollute the air, when in fact the wind will just carry the pollution toward a different city.

Sometimes I wish all LEED™ professionals would have more common sense and follow these laws of nature and their own environmental gut feeling - it is simply better living under a tree canopy rather than under a polar glacier. 

Elevating Urban Farms onto Rooftops

Green Team at Green Roof Technology, - Wednesday, January 09, 2013

By: Jörg Breuning

Photo credit: Kölner Wein Depot

Long before green roofs became necessity and rooftop farming was trendy in North America, Dipl.-Ing Markus Wittling was planning to elevate an entire vineyard on top of the Wine Museum in Cologne, Germany.  Build in 2002, the sloped green roof spans over the entire museum building of almost 20,000 square feet. It is the first vineyard on a roof, the first sloped rooftop farm and the first and oldest organic urban farm on a roof in the world.

In the middle ages Cologne was the most important wine trading town north of the Alps.  The "Weinmuseum Köln e.V." is honoring this factwith a brand new museum with astonishing and educational exhibits on wine. The green roof displays 40 of the most important grape species from around the world situated onto 720 vine stocks.  The soil layer (growing media) including granular drainage is approximately 27 inches deep and consists of a blend of porous volcano material like Lava rock and Pumice - materials in which grapes simply grow best. 

 This rooftop vineyard is a prime example of the performance of modern green roof technology and is ideal for educational purposes.  If you have a chance to visit Cologne, the Wine Museum is a must on your Green Roof Safari and your effort will be rewarded with amazing wine tasting

For more information: or simply contact us.



Solar Power (and Green Roofs) on the Rise!

Green Team at Green Roof Technology, - Friday, December 28, 2012

By: Samantha Yurek


Solar energy has been on a modest climb for most of its existence, but this year the solar power market jumped 71% compared to last year’s sales.  A growing renewable industry is a boost to our economy; over 93,000 Americans are employed within the solar business alone.  As the demand for solar installations grows higher, the prices will drop correspondingly.  This is already evident, in 2006 the price of a residential installation plummeted from $9 a watt down to $5.46 a watt.  Today we see prices around $ 4.00 per watt.

Even with the rise in solar sales, the US is still trailing behind Germany, Italy and Spain.  Around 20% of power in Germany is harvested from the sun only, but only around 11% of energy here in the Unites States comes from a collaboration of renewable resources (solar, wind, hydro, etc.).  Harvesting power from the sun is a smart idea.  Not only is the sun a renewable resource, but the process creates zero atmospheric emissions.  It’s clean and reliable!  Even with this spike in interest, solar power is still underused here in the United States because investors often look only at the capital costs. Capital costs of a Coal Power Plant are at around $ 2.10 (source Wikipedia) vs. around $ 4.00 for Solar.

Note that the capital costs are not the only determinant of the cost of the electricity produced. A coal plant needs to burn coal to produce power (a limited resource), while a solar panel and other renewable generation has no fuel input at all.

“Externality and insurance costs of energy sources” became in the 2010s recognized as equivalent to fuel costs as a decision factor. In particular for Nuclear and coal power plants but also for ground mounted Solar these costs can be deal breaking.

Roof mounted Solar power plants combined with a vegetated roof (extensive green roof) increases the capital costs by less than 20%. At the same time this marginal increase pays back in a short time due to the reduction in stormwater fees, reduction of the environmental foot print and recognizable increased in efficiency.

The synergetic combination of vegetated roof / Green Roofs with Solar is truly State-Of-The-Art and unmatched in modern green energy production and environmental protection.  

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