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Watch the 2:23 video Insurance/Financial Company, Stuttgart (FBB Green Roof of the Year 2014) – Project of the Week 11/24/14 from on the greenroofsTV channel on YouTube. For more information on this private project, contact Jorg Breuning of Green Roof Service LLC / Green Roof Technology at or 443.345.1578 and Heiko Schmidt of Optigrün international AG / Optigreen at or +49 (0) 7576/772.158. Also visit the following contributors:;; and See the project profile in German at baulinks. Read the September 20, 2014 Green Roof of the Year 2014 – 30 Years and Counting Press Release from Green Roof Technology and the August 15, 2014 30 JAHRE ALTE DACHBEGRÜNUNG IST GLEICH ZWEIMAL GRÜNDACH DES JAHRES 2014 in German from Optigrün/Optigreen.

Learn about the following companies in The Greenroof & Greenwall Directory: Green Roof Service LLC / Green Roof Technology and Optigrün international AG / Optigreen.

In 1981 one of the world’s largest insurance and financial services groups decided to build their local headquarters in the heart of Stuttgart. At that time the office building complex 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 dual purpose of a green work space combined with luxurious living in the downtown of a large city.

Constructed from 1981 to 1984, the roofs are one of the first projects where Jörg Breuning, CEO at Green Roof Service LLC / Green Roof Technology, was substantially involved in the realization. The green roofs are located different levels, generally assembled throughout the building campus – atop the above-ground parking garage, and office and residential areas. Most people in the offices have a view into the green spaces. While the site is accessible, many of the individual roofs are not. Yet some areas of the green roofs 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.

During the inauguration of the building, Prof. Hans Luz formulated his vision: “Integrating vegetation into the concept of our cities is an important contribution to improving climate, water balance and appearance. It has been noticed, that it is not sufficient to design parks and gardens on natural ground, but rooftops, garages, terraces, façades must be included.”

All green roofs together measure over 21,000 sf. This inner city oasis utilized an advanced Optigreen Green Roof System 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 also leaves enough room for precipitation to fill up the water storage under the plants.

The green roof layer structure (from the former optima system, the forerunner of today’s Optigreen system solutions) is composed of: protective membrane, root barrier 0.8 mm (fully welded and adhered to the concrete edging), 10 cm drainage type Perl 8/16, filter fabric mesh, 30-40 cm intensive growing media substrate type i, and plantings of shrubs and woody plants, lawn and perennials.

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

In 2014, the 30-year old roofs were looking in perfect shape and condition, and has fulfilled Luz’s intention. Subsequently it received two prizes for its 30th anniversary: It was not only awarded Green Roof of the Year by the Optigreen partner network (100 participants) during its annual directors’ meeting in Stuttgart, but just a few weeks later, the oldest green roof association in the world, the FBB (Fachvereiningung für Bauwerksbegrünung), awarded this private financial company project the “FBB Green Roof of the Year 2014” prize for their 30 year old green roof in Stuttgart, Germany (120 participants).

The roof is in as healthy condition as it was back in 1985 and so are all the participants from then: Optigreen has grown to be one of the leading system suppliers. Arnold GmbH is now lead by Otto Arnold’s son, Stephan. The planners have transformed into Arcass Freie Architekten and Luz Landschaftsarchitektur, and keep shaping green environments to work and live in Germany, while Jorg Breuning has moved to do exactly that in the United States.

“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 foremost an 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,” says Jorg Breuning.

Jorg continues, “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!”


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