Green Roof Service introduces the Lawn Club on Celebrity Solstice

2011-09-08T02:35:00.000-07:00

The Sky is Falling: A Critique of Failed Sloped Extensive Green Roofs

Tuesday, September 06, 2011

By Jorg Breuning

As of late we have been receiving more and more calls from building owners in distress about their green roofs. The most serious of these complaints being erosion problems on their sloped roofs. Sloped green roofs are a bit more complicated to design, install, and maintain than flat roofs and as a result people who disregard or don't know of the established FLL guidelines for sloped roofs, have created dangerous and costly situations ranging from mudslides to roof collapse.

One of the most infamous of these rooftop blunders was last winter in St. Charles, Illinois. The project was designed to be the largest sloped roof in the US and during a heavy snow storm the roof collapsed. Fortunately no one was hurt however the damage was devastating.

Why did the roof collapse? The problem lies in the drainage. Snow is frozen water and where you have more water accumulating on a roof you will also have greater amounts of snow accumulate. This insufficient or clogged drainage system and poor growing media is the most likely culprit in areas that held water or snow. All this added weight during an extreme winter put the roof way beyond its capacity.

Sadly, this situation and others like it could have been avoid simply by hiring a true expert and checking their performance history for similar projects.

To read more about the dangers of improperly design (PDF) sloped extensive green roofs and how to avoid them click here.

2011-08-18T08:32:00.001-07:00

“Extensive green roofs increase the fire hazard of our buildings and a green roof is a potential risk under windy conditions."

Are these statements true?
How safe are green roofs?

Grim Spring 2007
Jörg Breuning, Green Roof Service LLC

While in the Nineties in Germany green roofs spread faster than every bush fire the natural human fear of nature caused by green roofs grew as well. As much as fire helped us to step ahead in the evolution as much we are afraid of it and so it didn’t take long until the first fire experts spoke out loud their concerns. They pictured scenarios like the big fire of London in 1666 and fueled a hot discussion. The discussion merged down to the following questions: Can one spark ignite an extensive green roof? Can extensive green roofs provide enough fuel to sustain or even propagate fires?
Since my hometown Stuttgart is the leading green roof city in Germany it was no wonder that in 1988 all experts including city, county and state officials agreed to a large fire research program done by the Research and Material testing laboratory of Baden-Württemberg (Government).
Before they started with large scale field testing, they did the math or basically they made some burning tests in the laboratory first. It wasn’t really surprising that a bituminous waterproofing layer produces 50 kWh/m² which is 15 times more than an extensive green roof with dry grasses (3 kWh/m²). That means you can heat up your house much better with a bituminous layer as with a grass/green roofs. They also tested PS-insulation and ply wood – we know how this stuff burns. With this knowledge and knowing that it takes much less to set fire on dry plants (grasses) than on a piece of waterproofing the field research begun. During the following months (August until October) they actually tried to start fires on green roofs with a defined setup (with dry wooden wool) which was installed on the roofs and ignited.
They expected a glowing of the organic content in the growing media and they also thought that the dry plants will spread the fire immediately all over the roof.
Just keep in mind, at this time the organic content of the growing media was typically higher than the values in the actual FLL guidelines and so you also found higher plant varieties with consequently a higher amount of dead and dry plants.
After all this experiments and research just a short answer. It is nearly impossible to set an extensive green roof on fire which spreads over the roof or starts a glowing/burning of the growing media. The risk of fueling fires is 15-20 times higher on bare roofs with fully adhered bituminous waterproofing membranes as on extensive green roofs with grasses, perennials and Sedums. I guess in 1988 I installed approximately 2,000,000 sf of extensive green roofs - all on schools and kindergartens in the south of Stuttgart. Does that say something to you?
Today in Germany are at least 2 billion square foot of extensive green roofs built and there is no fire recorded related to an green roof. This research and further studies showed certain risks (i.e. sparks caused by burning grasses which can spread over the green roof by wind) which are minimized by clear definitions of green roof details and roofing details for green roof. There are considerations in building codes, German and European standards (DIN/EN). The FLL guideline always represents the latest State-Of-The-Art in addition to the above mentioned standards.
In Germany you typically get a 10-20% discount on the fire insurance when a seamless extensive green roof is installed.

In most cases the fire insurances offer a package which also covers damages caused by wind and storms. An insurance company wouldn’t give a discount if there is a higher risk in one of each; however that is only one aspect you can look at wind load topic. To backup my experience of nearly 30 years I contacted some of my friends in Germany. Since decades Dr. Gunter Mann and Dipl.Ing.Martin Henneberg are working for Optigreen and they did uncountable studies together with all major Universities in Germany and published exciting articles about green roofs as well. They maintain a close information network to more than 100 installing companies and partners. It is the biggest information resource I know and which offers a feedback of at least 20 million square foot new green roof construction every year. Speaking about this resource Dr. Gunter Mann was interviewing close to 80 installers about wind loads on green roofs. All interviewed installers look back on more than 15 years of experience and millions of square foot green roofs installed. Based on these experiences and their reports they confirmed my experience that wind erosion can happen on each building regardless the height of the roof or the height of the parapet. Most erosion on roofs below 60 foot is hardly recognized since it typically starts during the establishing phase of the plants (new installations) and the plants usually cover these areas soon. Large organic parts (wood chips etc.) and very lightweight aggregates ( less than 600g/ltr.) are blown away fairly easy and found all the time everywhere on the roof where they shouldn’t be. Most of the (hardly to see) wind damage on building below 60 ft is also caused by unique aerodynamics of the buildings itself. All installers agreed that even the smallest wind damage has to be fixed immediately with appropriate solutions to prevent further damage. It shows once more that green roof maintenance requires very high skills, well trained senses and the understanding of working with nature – not against it.
Regarding wind loads architects and installers put more emphasis on buildings over 60 ft. height and so surprisingly there are less minor problems recorded. A few big issues are well known and I like to share one true story with you:
Together with four landscape companies we installed in 1997 a 560,000 square foot extensive green roof on an over 60 foot high building. The building was also in an open field on top of a hill. I guess it was Storm “Lothar” just around Christmas with wind speeds up to 140 miles and wind gusts up to 180 miles. During this storm some large areas of the famous Black Forest where gone and 0.8% of the green roof on this big box, too (4000 sf). Sounds like a disaster? Yes and No. Yes because we knew about the exposed location of the building and that a green roof is vulnerable when plants are in the establishing phase. No, because the green roof was designed according the existing standard and the FLL guideline to withstand very high wind loads however all solutions (incl. concrete pavers etc) weren’t enough to keep things in place. It wasn’t a disaster either since the overall design was responsible that all components of the green roof remained on the roof on the roof and nothing felt down or was blown off the roof. Actually the insurance company paid for fixing the green roof since they were also happy that the force of the storm went into the green roof and not into the waterproofing or the lightweight steel deck. At the same time other wind damages on green roofs where recorded however all of them where minor (less the 1% of the area), nobody was hurt by falling Sedums but by falling trees, flying roof tiles and plywood sheets. I probably know the feedback of this article – you can’t compare the US with Germany. Regarding fire and wind load – yes you can, since with the impact of both mentioned elements a green roof works like a crash zone of a building and a green roof brings you up to a five stars crash rating – at least in the German insurance contracts. If I didn’t say it earlier, this article reflects my personal experience and nearly 30 years study of nature on green roofs. Instead of teaching being afraid of nature I help to understand, to work with nature and let nature work for me without stepping back in the Stone Age. The nature laws in physics, chemistry and biology are very complex however on this planet they are everywhere the same. I like piercing but I don’t like a nail in my belly button to hold my pants.

Jörg Breuning….let’s flip that roof.

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Green Roof Service LLC

2009-04-10T10:23:00.000-07:00

Green Roof Service LLC is the first company in the United States specializing in professional green roof services. Jorg Breuning is the founders and he has 30+ years of combined green roof experience which is by far unmatched in the United States. Jorg designed, specified, installed, supervised and monitored more extensive green roofs installations in Germany than there are currently in the entire US (2009) - multi millions of square feet.

With this unsurpassed background Green Roof Service LLC has the best assets to team with architects, landscape architects, developer, general contractors, roofing manufacturers and installers, landscaping companies, suppliers or structural engineers to foster highest quality for any green roof application or any green roof systems for commercial, residential, and institutional structures which includes new construction, retrofits and ongoing maintenance services.

Green Roof Service LLC is obligated to teach, develop and apply advanced green roof solution in the entire United States and they are the only firm in North America actively transferring proven green roof technology, standards or guidance from leading countries in Europe – especially Germany.

Green Roof Service LLC certainly understands their world leader ship and being the first green roof experts in the United States of America and is proud to be mentor and supporter for most of the early key players in the American green roof market including the North American Green Roof Association (GRHC). Green Roof Service is part of selected committees at GRHC, reviewing papers for presentations and writing articles about selected topics to fuel the North American market with experience based information.

Green Roof Service’s co-founder Jorg Breuning consulted the nation’s first green roof research program at Penn State University in State College and systematically helped to make American’s aware of green roof technology since 1989. He provided key information, site supervision and hands on training for many award winning projects like Chicago City Hall, Chicago, IL, Chicago Green Technology Centre, Chicago, IL, Peggy Notebaert Nature Museum, Chicago, IL, Oaklyn Branch Library, Evansville, IN, Heinz 57 Center, Corporate Headquarters, Pittsburgh, PA, Carnegie Mellon University, MV Celebrity Solstice Cruise Ship.

Green roof services focused on specific projects are the application or practical sector at Green Roof Service LLC. The sector of theory based facts is covered with ongoing lectures at University, Colleges, municipalities, organizations, associations and architects so to speak at Toronto Botanical Garden, New York botanical Garden, GRHC conferences, Sustainable South Bronx New York, The Bronx Overall Economic Development Corporation, Westmoreland Conservation District, Roofscapes Inc. conference, FBB Association, Tecta America Company meeting, Royal Caribbean / Celebrity Cruises, Earth Pledge Foundation, Rotary Club Bel Air, A3C Architects, Lancaster County/City and more.

Last but not least Green Roof Service’s knowledge is also incorporated in many brochures, company information, text books and reference books such as Green Roof Handbook RCT, Skyland USA LLC, Cetco Garden Roof Assembly, GAF greenscapes, “Green Roof Plants” by Ed Snodgrass, FLL Guideline, FBB Association, ASTM and SPRI standards.

Green Roof Service at a Glance

2009-03-25T08:33:00.000-07:00

When Celebrity Solstice launches in December, 2008, vacationers will find that the grass really is greener on a Celebrity Cruises vacation. http://www.celebritycruises.com/
The ship will present an industry first on the top deck of the ship: real, growing grass, set in an innovative new country club environment known as “The Lawn Club" on Celebrity Solstice invites guests to enjoy bocce, croquet and picnic with wine and cheese. “Feel the grass between your toes or practice your putting promises the advertising of Celebrity Cruises.

Find on YouTube a great video about the LawnClub (paste-copy) http://www.youtube.com/watch?v=ZAqcrp7LQFU

Ship FactsOccupancy:
2,850Tonnage:
122,000 Length:
1,033 ftBeam:
121 ft Draught:
27 ft Cruise Speed:
24 kts Inaugural ---- Revenue Cruise Date: November 23, 2008 ----

But Let’s Start from the beginning:
In April, 2008, Royal Caribbean Cruise Lines and Celebrity Cruises awarded Green Roof Service LCC the contract to design, engineer, install and maintain a green roof on their largest ship ever built in Germany the Celebrity Solstice. Green Roof Service LLC developed and designed the entire setup for the Lawn Club and subcontracted the installation to Borchers GmbH Company in Papenburg, Germany.
“We just installed a green roof on an office building at Meyer Werft and now we continue on their ships joked Bernhard Mescher, engineer at Borchers Company.

Richard D. Fain, Chairman of Celebrity Cruises said, “Everything about the Celebrity Cruises brand is authentic. Our vision for a completely genuine experience demanded nothing less than real grass, and we sought out the right innovation to make that vision a reality.

Realizing the need for authenticity, flexibility and durability in this unusual and highly demanding design, Uwe Harzmann, CEO at Optigreen AG assured, “We are able to modify our components and we will meet all requirements including the FLL Guidelines (German Green Roof Guidelines - Forschungsgesellschaft Landschaftsbau Landschaftsentwicklung e.V.
Green Roof Service's list of requirements had more than 100 items and many things seemed contrary to one another.

Here were some of the most important key requirements and considerations for designing a sea-faring green roof:

- The layer set-up must support the Arctic, Northern Europe, Mediterranean and tropical weather conditions.
- Fire prevention to meet international marine fire standards.
- Wind resistant for wind speeds 100 mph and wind gusts over 120 mph.
- Stable against sliding - ship tilts up to 12° or 27%
- Highly salt tolerant
- Environmental friendly materials and run-off behavior.
- Maximum weight: 130 metric tons.
- Prime turf grass for activities like Bocce, croquet and golf putting.
- Resistant for foot traffic.
- Comprehensive set-up to exchnage grass easy and fast.
- Maintenance program, physically fit and well trained lawn keepers.

Logistical Challenges:

When sitting on the Solstice on the grass of The Lawn Club in the Sunset Bar, guests will also enjoy spectacular views in a relaxed atmosphere 120 ft above sea level. Everything looks nice, green and beautiful and no one could even imagine the construction challenges we encountered along the way. The Solstice is the largest passenger ship ever built in Germany and keep in mind that the ship yard is 50 miles off shore. Getting the materials up on deck 15 stories high within a two week time frame from a ship yard where more than 2,500 people and more than 50 contractors were working all at the same time, while hundreds of containers were being loaded sounds like an impossible endeavor, right? Yet Meyer Werft built the $750 Million Solstice in only 10 months where time is money and everybody and everything had to work 24/7.

The Celebrity Solstice embraces many eco-responsible elements and she sets the bar very high when it comes to sustainability. In addition to the half-acre green roof, here are some other environmentally-friendly features:

Entire ship with mostly LED lightning technology saves over 20% of power.
Four Hybrid (Common Rail Diesel-Electro) engines.
All roofs have photovoltaics (including glass roofs).
Advanced biological waste water treatment facility.
Recycling and separation of trash and waste.
Fresh water production with reused heat and reverse osmosis and low chlorine.
Reuse and refining of oil on board.
Run-off collection tank only for green roof.
Corporate leadership with “Save The Waves” program.

Depending on many issues (climate, foot traffic, etc.) the grass might need to be changed to warm season Bermuda grass. When? I don’t know since this has never done before; only time will tell. The only thing I know is that the system (the layers set-up) will work in every climate, every region and with every type of grass where ever the ship cruises.
We literally demonstrated that modern green roof technology and the German Green Roof Guidelines (FLL) work all around the world from North to South and West to East. Rest assured the FLL is a valuable guideline for plantings on impervious areas on Earth (and sea).There is no better demonstration of a high quality project than on the truly first mobile green roof traveling the seas of the world.
We simply delivered what was ordered and nobody else was able to deliver: Nice, green, and beautiful.

By Jörg Breuning, Green Roof Expert and Consultant j_breuning@yahoo.de or visit greenroofservice.com

Visit: GRHC Award Winner

http://www.greenroofs.org/index.php?option=com_content&task=view&id=1523&Itemid=153