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The Best Green Roof System

Green Team at Green Roof Technology, - Saturday, August 01, 2015

The main purpose of an extensive Green Roof is stormwater retention and delaying stormwater runoff amongst many other added values.

Above: An Irrigated thin layered Green Roof System – without irrigation it would be dead.

In the last decade in North America, we've seen many Green Roofs where the intended plants never really flourished. I estimate that in the US at least 50% of the green roofs are not performing to their fullest potential. This can be observed by simply looking at the most obvious of indicators, the plants themselves, regardless if they were planted on purpose or somehow found the space to take root. 

Most of these less healthy extensive Green Roofs are thin-layered systems, pre-planted boxes (often called modular systems or hybrid systems), Green Roof Systems from roofing manufacturers with ineffective components, single source warranty-systems, or design intents without consideration for the needs of plants. Typically these systems much more costly (whether thin or thicker) and the mid to long term results are often far below systems that are assembled in place with common sense.

 

Thin-Layered system with irrigation - doesn't work and doesn't retain much water

We all know that the transition from being a common nursery-grown plant (including pre-planted boxes) to the extreme environment of a rooftop poses severe challenges. Green roof plant nurseries typically have "great" advice and recommend the installation of temporary or permanent irrigation systems. In some areas this might be helpful when operated correctly but in all cases this advice is defeating the purpose of an extensive Green Roof (water retention). In almost all cases any type of irrigation caused a spiral of failures and it is wrong to irrigate extensive Green Roofs in areas with limited water for the cause of just having a green roof (Green Washing). Most company sponsored experts don’t see the entire picture or they only see the short term profit and commission (“Mow-Blow-Go”).

If a problem occurs and since many Green Roof system developer lack the proper and specific green roof horticultural knowledge, they may not be able to identify problems by simply looking at the indicators (the plants). This could cause the problem to gain momentum. In addition, the false conclusion that technology (Google search, Apps, synthetic growth media or sophisticated soil moisture control devices) can fix the problem supports my theory of hardly experienced or misinformed green roof professionals. They rely heavily on technology to fix any issues and miss the big picture.

Nature has the ability to take care of itself, as long as the appropriate design, materials and plants are used in addition to being familiar with the immediate location and climate.

Thin layered, super lightweight systems or systems with “innovative” components are just by physics not meant to retain “more” stormwater for the plants or they retain too much water for specific plants. As a matter of fact the costs for retaining stormwater in thin layered systems are extremely high comparing to a standardized extensive Green Roof with a thickness of 4-6 inch (depending on location). Besides the initial costs the lack of water retention (don’t forget all studies are done by the companies!) won’t support any significant bio diversity plus the operational costs (because of the required irrigation) are tremendous over time. Typically these Green Roofs never pay back with they are not utilized for “Green Washing” purposes in advertising.  

Irrigated extensive Green Roofs and/or thin layered, super lightweight systems (below 25 lbs/sf) will increase the nutrient pollution in runoff, require higher fertilization application, have hardly any tendency for self-healing, and may increase the pressure of unwanted plants and have a high risk for failure. Irrigated extensive Green Roofs are not environmentally friendly in most loactions!

Green roof designers and green roof professionals must understand that certain advertising, studies, White Papers or project references are all assembled by specific manufacturers and their goal is to make money – unfortunately on the back of a very advanced technology and on the back of their clients.

When we advise our clients they get the full picture because we have seem all solutions in the last 35 years, we have tested them and we are currently working millions of square feet where these systems require upgrades, reinstallation or massive repair (around 20 million in damage so far).

We also help our clients doing it as efficient as possible and to get their money back from prior failures through warranty claims and sophisticated lawsuits. This might help to standardize the function of Green Roofs and helps to get the black sheep out of the market. The building owner has a right that things are done right from the beginning.

Never irrigated in the last 10 years.

Leading Green Infrastructure since almost 150 Years!

Green Team at Green Roof Technology, - Friday, July 10, 2015
 Leading Green Infrastructure since almost 150 Years!

Stuttgarter Nachrichten

Picture: Stuttgarter Nachrichten


Living Green is not just an empty phrase for City of Stuttgart, Germany.  The history goes back almost 150 years as the “Stuttgarter Verschönerungs Verein” was founded. A powerful Association with an authority comparing to today’s City Department of Parks and Recreation. Even during the Nazi-Time the Association was entirely independent and was able to protect historical buildings, Parks and to increase living green with new parks and living green recreational areas.

Based on this history it was no accident that Stuttgart is the pioneer of an unmatched progressive Green Roof program in the 1980’s and the City of Stuttgart is still the leader with the most Green Roofs in the world.

Just recently the City revised the Building regulations for the entire State Baden-Württemberg that every building owner has to implement more living green. A controversial discussed item in politics because some people understood that as forcing Green Infrastructure – but it was meant to inspire building owners to value Green Infrastructure as an investment for the future with related high savings for operational costs.

In an newspaper article of Stuttgarter Nachrichten the new building requirements are explained including the benefits for the local infrastructure and the lasts high demand for well trained and educated Landscape people.

I was very excited to see that they used a current picture of a Green Roof project I installed in 1999/2000.

This Green Roof is a demonstrating project at a landscape company and covers their truck parking. The depth of the Green Roof reaches between 4 inch to 12 inch – from Sedums, perennials, shrubs to trees that grow over 15 feet. Since it is on a roof the reflecting pond is rather shallow, has a water feature and is lit up at night to create a private out door space for the company owner. The City of Stuttgart, Germany is a place where ecology and economy is closer together than in any other place on Earth I know.

2001all rights Jörg Breuning
Picture: Jorg Breuning taken one year after installation

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.

Single Source - Multiple Problems

Green Team at Green Roof Technology, - Friday, January 10, 2014

By: Jörg Breuning

2013 was another very successful year for green roofs and the green roof industry. However, at Green Roof Service LLC/Green Roof Technology we discovered a trend that might affect the industry in the long run. 

The quality of green roof installations didn't improve as much as the industry grew. We have received more calls about poorly installed or poorly functioning green roofs than ever before. Most of these (green) roofs were installed in the last two to three years and the lack of proper engineering and maintenance has caused issues. These issues are time consuming to fix, require replanting, and the installation of additional growing media or even a permanent irrigation system (even in a wet year like 2013!).

The majority of these under-performing green roofs were under a Single Source Warranty and so our first response was: "Go back to your warranty provider." For green roof owners, this was typically the start of a long odyssey. Odysseus never gave up- but with all the issues presented, my clients were quick to give up because the Single Source Warranties are well-phrased and manufacturers are more likely to argue than take action. Arguing with a piece of paper, written by attorneys, twisted and tweaked by companies' legal departments is an uphill battle. No wonder these numerous stranded people decide to call us.

If the client would have taken his money to the bank, rather than spending it on the warranty (typically $1-$3 per square foot) things could have been much easier and cheaper. On top of that, our costs for designing, engineering and overseeing the installation and maintenance would have saved additional money and no problems to start with.

 

In any construction process we are meticulous with our details, quality of materials, craftsmanship and maintenance. We also offer low bureaucratic, simple and efficient solutions to make your green roof last far beyond three decades. Our green roofs wouldn't need any artificial irrigation, and will prove to not cost as much initially, as well as having the potential to be paid back in less than seven years.

It is our goal for the future to support the growth of the green roof industry (and the plants), one by one making our clients happy. Only happy clients can help us - and the green roofing industry.

Cradle to Cradle Concept on a Green Roof

Green Team at Green Roof Technology, - Wednesday, September 25, 2013

"The world will not evolve past its current state of crisis by using
the same thinking that created the situation"  - Albert Einstein

 

The Cradle to Cradle theory reappeared in 2002 with the release of Cradle to Cradle: Remaking the Way We Make Things by William McDonough and Michael Braungart. A concept dedicated to mimicking nature in which products can be fully recycled. Instead of materials having a specified lifespan, they can indefinitely be transformed into other products. A design created to enrich and benefit the environment even as products are manufactured and used.

Recently, the cradle to cradle design has been proposed for a green roof project in the United Kingdom. By-products from the London Sustainable Industries Park will be collected and transformed into aggregate material used for drainage purposes on green roofs and walkways.

Green Roof Technology has many opportunities to use recycled materials in our projects - as long as the green roof's efficiency isn't compromised or becomes the neighborhood landfill.

New Instant Green Roofs

Green Team at Green Roof Technology, - Tuesday, September 17, 2013

Joe’s Paint Releases: New Instant Green Roofs

Our favorite environmental expert and green roof research specialist Joe is up to his old tricks.  Joe hit the PR circuit again this week releasing a full range of new roof greening products. 

Not satisfied with only offering a green roof in a can, Joe is now offering a full line of instant green roofs.  His new products include a highly reflective white paint for roofs and façades. The can comes with a pair of sun glasses and two cartons of greasy sunscreen (SPF 90) for an entire neighborhood.   

The best green roof and green wall product is already successful on the markets: An artificial grass mat that can be rolled out.  Joe has the fake grass in multiple colors to create Blue Roofs, Brown Roofs and Red Roofs. The good thing is, that after a season you can also fill-up the landfills with toxic waste and contributing your part to a healthy growth of the economy.

 Grass Test

Joe is very excited about the new product line and promises: “Next year we come up with an entire line of fake honeybees, polyethylene spiders and colorful plastic butterflies with remote control. Just before Christmas we will also see artificial flowers and Christmas trees (comes with a fake turkey). “

 

 

 All fake grass products are tested under real conditions. 

If you want to walk on grass without having a green roof we recommend the grass Flip-Flops. Retaining almost 100% sweat and you can’t run-off.

 

We all love Joe here Green Roof Technology because he is constantly pushing the green roof industry and green technologies to new heights. 

Orders and feedback: info@greenrooftechnology.com

Episcopal Academy Installs More Green Roofs

Green Team at Green Roof Technology, - Wednesday, July 10, 2013

On July 9th, three more small extensive green roofs were installed a top the Academy’s High School Building in Newtown Square, PA.  The High School has a number of glass walled hallways that look out over unsightly black rooftops.  The glass walled hallways provide a spectacular viewing area for the green roofs.  This year we covered almost three times as much roof area as we did last year, bring the Academy’s total green roof count to five.

Once again, Micah from Urban Ecoforms joined us to lend his experienced hand at installing green roofs.  From the picture below you can see that Micah was in rare form and simply thrilled to be freed from his recent solitary confinement atop his current project in West Philly.

While we were installing the green roofs, we could not help but stop and admire the incredible lushness of the green roofs we installed last summer, especially when last July was brutally hot and dry.  


Micah Shapiro (Urban Ecoforms) striking a pose with the beautiful Academy's quad in the background.  

Andrew after spreading the last of the Sedum cuttings.  Seen below is one of the green roofs we installed the previous summer.


New Sun-Rootâ„¢ System Installed

Green Team at Green Roof Technology, - Tuesday, June 25, 2013

By Samantha Yurek

Last Wednesday, June 19th, Green Roof Technology traveled to Northern Virginia to help install a green roof demonstration project, complete with a Sun-Root System™. Being the latest achievement in sustainable design, the Sun-Root System™ effectively combines solar power with vegetated roofs.

Working with the company Prospect Solar, we were able to help preserve the environment and promote renewable energy. Prospect Solar was established in 2010 by the well-known Prospect Waterproofing Company. One of the leading specialty roofing companies in the DC area, they have been successful for over twenty years. Prospect Solar has been following in their footsteps, creating more sustainable alternatives to the traditional roofing practices. 

Swarthmore College Performing Arts Center Green Roof Install

Green Team at Green Roof Technology, - Tuesday, June 18, 2013

 

Our relationship with Swarthmore College began nearly a decade ago. We have had the privilege of working with the college on several other green roofs, a few of which appear on the front cover of popular green roof books.

This past Friday, Andrew went to Swarthmore College to oversee the install of the college's newest green roof. The Furbish Company was awarded the contract to install the 31,000 square foot green roof.

On a beautiful afternoon, the Furbish installers added the final touches on one of the lower roofs. The custom designed green roof is a hybrid single-course system that utilizes heavy-weight drainage and retention fabrics (provided by Resource Conservation Technology), a 100% pumice growing media layer (provided by Stancills Inc.) and sedum mats (by Sedum Master). This system was utilized due to the roof's weight capacity limitation.

 

 

 

Energy Cost Savings Through Green Roofs: A Myth

Green Team at Green Roof Technology, - Monday, June 10, 2013

An Executive Summary of Facts by Jörg Breuning

It is unavoidable and common sense that wearing wet clothes in winter will end up in hypothermia. Wearing the same wet clothes on a hot summer day, might actually help to feel cooler - not to be confused with feeling more comfortable. If we have only one set of clothes, for all four seasons, they would typically be made up of two layers. The first layer protects against direct environmental impacts such as sunlight, rain or wind and the second layer usually consists of a breathable layer for comfortable wearing and controlled air circulation. 

Source: Columbia

I have learned on my travels all across different desserts on earth that these layers reduce temperature increase on hot, sunny days, but at the same time can reduce the loss of body heat during extremely cold nights. Indigenous people of extreme environments have learned this lesson over centuries and were able to survive under these circumstances with this simple layer strategy. My father always used to say: "What is good for the cold is also good for the warm."

 Any man-made structure is nothing more than a body that requires consistent 'body temperature' to make it usable for the purposed design. A building without reliable all-season clothes is worthless or requires a tremendous effort (energy or operating costs) to make it useful.

Helping to make a building useful for people, the 'coat' consists typically of an insulation layer covered with a layer to protect against the elements (waterproofing, roofing membrane). Since we all know that the protective sheet will deteriorate over time this sheet (waterproofing) has to eventually be renewed, a process experts call re-roofing, which usually happens every 18-25 years.  

It is proven by my experience (since I have been designing and installing green roofs for 35 years) that a green roof can double the lifespan of the roof. The green roof acts like an additional all season two-layer system on top of the roof where healthy plants are the first layer, protecting against direct environmental impacts. The green roof growing media (green roof soil) is the breathable layer.

There is only one difference; the breathable layer (growing media) on a green roof is also the basis for the well-being of the plants and must be able to store water and air at the same time for a healthy growth. If this layer doesn't fully support the plants (and only the plants) the entire coat does not function and the plants tend to indicate this by suffering or a change in plant varieties present.

Above we learned that a wet coat in winter causes problems because water is not a good insulator and so we have to consider heat loss in winter when speaking about green roofs. We also understand now that dry green roof soil in summer will store heat (in the aggregates) and increases the cooling needs.

A green roof (and green walls that grow on growing substrates on vertical surfaces with consistent irrigation) are only thermal masses with hardly any insulating values. Considering these facts, building owners should be cautious when someone tells them that green roofs are good insulators. This is just not the case, especially if the building envelope is not insulated correctly in the beginning. Fixing heating and cooling loss simply through green roofs and/or green walls is impossible or a short-term solution.

With all the current research in this field, it's surprising to me that people still claim green roofs are good insulators. Additional insulation below the original coat is necessary (waterproofing or walls) to make the most effective roof (cost wise and physically) compared to any vegetated layer combined with growing media of growing substrate.

However, the thermal mass "green roof" certainly has lifespan extending properties for the waterproofing (and again, I can confirm this with projects spanning over 35 years). This is the key to start thinking in long terms (50+ years) in the building industry and is the most sustainable approach. Longevity is hardly considered in LEED™ certifications and with less emphasis on longevity, many awarded LEED™ buildings might fail for a certification because they can't be upgraded easily when the costs of energy increase. I am not referring to how wasteful the footprints of many of these 'innovative' building designs are.

Photo DM Products: Penn State's futuristic Millennium Science Complex earns LEED Gold for this space-wasting empty over hang. The 'water head' of the campus (or of their bureaucracy). Pants can not even grow underneath - how can people survive?

In the last 35 years, energy costs increased eight to ten times (!) and are expected to grow accordingly over the next three to five decades (or the lifespan of a green roof). Knowing this, selling a green roof for insulation purposes will unavoidably end up in a costly disaster for the building owner. Removing a fully functioning green roof in less that 25 years after installation, simply to add to more insulation, meet future requirements or to keep heating and cooling costs low.

Green roofs do not extend the life span of selected, important building components dramatically. Increasing the lifespan of any building is the best environmentally friendly approach in the building industry and the most efficient way to reduce costs for the owner over decades. Although, if scientitst and green roof professionals often do not understand this unique property of green roofs and don't design underplaying components accordingly, the building owner won't be very happy in the future. In 20-25 years when parts star needing to be replaced, a second green roof will be the last choice of the building owner because it will simply be additional costs with few benefits as originally promoted.He might not understand why he should disassemble a perfectly functioning and well established green roof, precisely when certain individuals led him in the wrong direction in the past.

Conclusions:

•  As a building owner be careful when people try to sell you green roofs as a good insulator without mentioning that additional insulation is necessary for the building for future energy needs.

•  Building owners have to understand that any available research about the insulation value of green roofs reflect only a current snap shot and potential savings in a very short time period (less that half life time of a green roof) and they are worthless when the intention is to build for half a century.

•  There are no energy  studies completed over a 50+ year time span comparing a green roof (plus additional insulation) and a conventional roof that will be re-roofed with additional insulation 20 years from now (typical re-roofing practice)

Trust only experts that recommend additional insulation under the green roof because then they expect that your investment will last a human lifetime, which will be profitable but also affordable during this time. Designing the roof (or wall) to last for five decades or more requires a lot of responsibility and expertise of the designers - if they value their customers.

 


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