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Fireworks and Green Roofs

Green Team at Green Roof Technology, - Thursday, July 04, 2013

Fireworks and Green Roofs

Practically all dry organic materials are combustible at relative low temperatures. Roof shingles or many waterproofing membranes on roofs are typically petroleum-based products (including Asphalt) and they is hardly a difference to dry organic materials. Some products are equipped with chemical fire retardants that could decrease the risk of spreading fire, not the risk of leaks cause by impact.

The living vegetation of functional and well-engineered green roofs contain high moisture contents and most plants (especially succulent plants on large extensive green roofs) have a fraction of the energetic potential comparing to all other components used in a building. The green roof growing media (soil for the green roof plants) is a blend of different mineral components with an organic content of typically less that 15%. It is practically impossible to set this material on fire – not even considering the natural moisture content.

Many fires or leaks on roofs caused by consumer or display fireworks could have been prevented if the building would have had a fully functional green roof or a well-maintained conventional roof (regular removing of organic debris from the roof and gutters).

A fire is the worst-case scenario; however in most cases smoldering firework parts (and cigarettes) are causing leaks on unprotected roofs that are discovered much later. These problems are unknown on functional green roofs. When a green roof prevents a leak or even a fire it is typically not recognized but the payback is right there.

Nature is (literally) so cool.

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.

 

Rooftop Farming an Environmental Nightmare

Green Team at Green Roof Technology, - Tuesday, June 04, 2013

By: Jörg Breuning

Companies spend millions of dollars on creating rooftop farms to demonstrate how "green" they are. There is no doubt advertising with living green is a good idea because it makes the customers believe that the company practices environmental leadership.

However, the reality looks very differently.

Recently a food company started a huge campaign promoting their rooftop farm (and their green leadership) by opening a 17,000 square foot rooftop farm on the East Coast.They were optimistic that they could grow 10,000 pounds of produce during the short growing season. This is approximately 25% over the average vegetable and berry crop yields estimated for New England on the ground during a good year, based on traditional irrigated farmland.

Since environmental conditions on rooftops are more extreme, achieving this goal seems ambitious and will require higher amounts of water and fertilizer. With more moisture in green roof soil the main benefit of green roofs (stormwater retention) is sacrificed and the run-off will most likely now contain more nutrients than in the run-off from traditional farms. Nutrients are already the number one pollutant in our waterways.

Based on these harsh environmental conditions growing crops on rooftops will be more labor intensive.

A 17,000 square foot rooftop farm requires approximately 300 tons of engineered growing media (soil) or 672,000 pounds in order to grow an average of 8,000 pounds of produce a year. In other words, it takes more than 80 years to grow the equivalent crop weight that was transported up onto the roof in the first place. This does not include the tons of water, fertilizer or structural support for the building that has to be shipped to the city and hoisted up on to the roof to start and maintain the garden.

Roof top farms ultimately increase the shipping (costs) of goods into cities. Shipping produce from a farm located on the ground is cheaper and more efficient because everything necessary to sustain the farm is already at hand. The food from rooftop farms is being transported a shorter distance creating a false sense of environmental responsibility. When in reality, the amount of materials essential to implement and maintain a rooftop farm outweighs the good in this situation.

Consider this: every person consumes 200-400 pounds of produce in a year (Profiling Food Consumption in America in 2000, Agricultural Fact Book) and an average of 8,000 pounds feeds around 20-40 people and requires at least one full-time, skilled farmer.

On a traditional field, one farmer can easily manage a 10-20 times larger area with a higher yield per acre using organic principals, which are not even discussed with most roof top farms.

Buyers of food from companies with rooftop farms are misled by advertising and are paying more for their goods while supporting a trend known as Greenwashing.

Jörg Breuning welcomes people who want to learn from decades of green roof experience - askjorg@greenrooftechnology.com

 


Green Roof Irrigation Revisited

Green Team at Green Roof Technology, - Saturday, June 01, 2013


About a month ago the blog, Irrigation on Extensive Green Roofs, was posted on our website explaining why irrigation is an unnecessary component of any extensive green roof. A green roof is an efficient system that should function perfectly on its own in the given environment. An extended version of this article was recently posted on Greenroofs.com. You can check out the whole irrigation article here!

Jörg Breuning welcomes people who want to learn from decades of green roof experience - askjorg@greenrooftechnology.com


Green Roof Performance

Green Team at Green Roof Technology, - Wednesday, May 29, 2013

By: Jörg Breuning

 

Extensive green roofs are a thin layer of high performance components that allow a wide range of plants to grow on them. These plants have adapted over thousands of years to extremely harsh environments and are typically found in alpine regions, on natural rock debris (scree), deserts or tundra. Besides the extreme climate conditions in these areas, there is a very inconsistent supply of water or lack of water retention because of missing components in the soil (no fines, no organic).

In other words, these are typically locations where plants have to be very specialized. Once they have adapted, they are awarded by less competition of other plants - plants that require deeper, richer soils with a fine granular distribution line or high organic content.

Plants from these extreme conditions have not learned to compete with plants that we typically prefer for our gardens or our farms. Experienced horticulturists and plant collectors understand very well what it takes to grow these survivors, in locations other than their natural habitat. These experts are able to create an environment that supports these plants to prosper. These man-made environments are an example of modern green roof technology via extensive green roofs. Natural coarse, porous aggregates (pumice, lava rock) prove to be the most successful way to accomplish a proper environment. The porosity of the materials allows high water retention with simultaneously high air content. Also, this can be done very inexpensively and on a large scale. Modern green roof technology is engineered to ensure that every raindrop will penetrate the this soil layer immediately - soils with high organic content take too long for water to penetrate, resulting in standing water and consequently erosion. 

Some people may try to get around some of nature's principals, essentially reinventing the wheel in regards of extensive green roofs. They may also try and maximize other potential benefits (including personal profits), but end up sacrificing something else and in the worst case plants will suffer and possibly die.

The plants, whether they were intentionally planted or not, are an indicator for the performance of any green roof system. If any extensive green roof system becomes high maintenance, requiring irrigation or extra nutrients, the whole purpose of the green roof is defeated. Understanding these complex synergetic effects don't take a PhD, green roof professional training, or the internet - it takes decades of experience in the field, the patience of gardeners and common sense.

Modern green roof technology - as described in the FLL guideline - combines all these decades of experiences and makes things as simple as possible for novice green roof applicators - but it sure doesn't try to simplify the process. Einstein had some good advice on the subject, "Make things as simple as possible, but not simpler."

Jörg Breuning welcomes people who want to learn from decades of green roof experience - askjorg@greenrooftechnology.com

Irrigation on Extensive Green Roofs

Green Team at Green Roof Technology, - Thursday, May 02, 2013

By: Jörg Breuning

The main purpose of an extensive green roof is stormwater retention and delaying stormwater runoff amongst many other added values.
 
Above: An Irrigated Green Roof 

In the last decade, I'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 pre-planted boxes, or commonly known as modular systems. Not only are these systems much more costly, the mid to long term results are often far below systems that are assembled in place and at the time of installation.

I 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 more permanent irrigation systems. This advice is defeating the purpose of an extensive green roof and shows that asking self-appointed experts can cause a spiral of failures. Since many green roof installers lack the proper 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 less experienced or misinformed green roof professionals. They rely heavily on technology to fix any issue 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 climate.

Green roof designers and green roof professionals must understand that less is often more when it comes to extensive green roofs. No building owner wants to irrigate their roof in short, mid or long terms. There is no need to make a green roof more complicated by using multiple synthetic or plastic layers. LEED™ certification supports using gray (recycled) water for green roof irrigation; but what is the point of watering an extensive system when it's main purpose is to retain stormwater? Common sense and experience are the only two things that will aid in planning the perfect green roof.


Above: An Unirrigated Green Roof

Implementing irrigation on an extensive green roof is a clear sign of not understanding the basic principles of horticultural techniques or the laws of nature. Irrigation reduces the water retention, increases the nutrient pollution in runoff and requires higher fertilization application. Irrigated extensive green roofs are not environmentally friendly, not economically feasible and have hardly any payback for the building owner.

I tell my clients if they have an offer or design for an extensive green roof that includes irrigation - be cautious!

 

Green Roof Industry - learning by (not) doing?

Green Team at Green Roof Technology, - Sunday, March 24, 2013

For eleven years, the green roof industry has been running into the issue of finding a lack of Sedum cuttings between November and May. Green roof plant nurseries are not able to produce Sedum cuttings during this time because they obviously never learned better. During this time they rather grow these plants in pre-vegetated plastic or metal boxes, sitting in a controlled greenhouse for bigger sales in late spring and leaving the clients alone later when exactly these expensive and high carbon foot print containers do not acclimate in their final destination. They call themselves green roof plant experts but hardly understand the typical life cycle of the plants they are growing. 

When average temperatures drop most Sedums (most plants) store their nutrients and energy produced during the growing season in their stems and roots. The best indicator for that is the changing color of the leaves in the fall and when under stress. Once these reserves are stored in the little stems, they are extremely powerful and “programmed” for rooting - not for producing leave mass.  Many Sedums root quicker in winter than in hot summers where they have to deal with high evapotranspiration because of their denser leave mass while their roots are not able to supply them with water to offset the water loss.

Utilizing Sedum cuttings on green roofs can reduce the cost for plants and planting by 90%, assuming the applicators know what they are doing. At the end, the overall costs will drop dramatically which leads into more green roofs and less subsidies from public agencies and non-profit groups. The plant pieces broadcasted in winter are most likely adapted to the conditions in their final location in less than 2-3 months and hardly require watering on hot spring days or in summer. This also reduces maintenance time and costs.   

    

Jörg Breuning: “The lack of common sense and real expertise is the biggest problem in the North American green roof industry.  My person is controversial discussed, many feel intimidated based on my experience and that I address problems directly, which are avoided by other professional or trade associations. I see myself as the stimulus in a literally growing industry.

From an environmental point of view longevity at acceptable costs, low maintenance, no supplemental watering, and the long-term health of the plants are crucial for ongoing success. Customer orientated work requires that we adjusted to nature – nature will never adjust to humans”. 

Modular Office Farming – Hybrid Office and modern Green Roof Technology

Green Team at Green Roof Technology, - Tuesday, March 19, 2013

Now that rooftops have been discovered to be a potential area for urban farming, many people believe this this is the solution for providing healthier and locally grown produce.  They believe in this place despite its over average air pollution, lack of natural symbiotic opponents, high costs for water, poorly nutrient retaining soils, high labor costs and no machinery.

Yellow PepperHowever and completely disconnected from all the above mentioned disadvantages food can also grow in the inside of any building.  Modern green roof technology implemented in old yogurt containers to act like a modular system and can easily find a place close to a light source.  Depending on the system, they require less than once a week watering.  The water could even be recycled cold coffee (no sugar), tea or flat sparkling water before it is dumped into the sink.  Instead of sieving out of the tea leaves or coffee grounds these waste products can be supplements to regular plant fertilizer.  The run-off of these simple systems is zero since nobody wants water puddles in the living room, office or conference room. The results can be remarkable and some additional vegetables for lunch are always good.

The systems work without high tech, with fully recycled and recyclable materials, comes without an App, no power outlet and any other gimmicks.

The fresh green of the plants creates a nice living and working atmosphere, keeps the humidity in the comfort zone and additionally cleans the – already filtered – air.  In our office peppers and pineapple are the favorites.  

 

 

Green Roof Service LLC/ Green Roof Technology 

Your Green Roof Technology team is able to develop low maintenance concepts for plants far beyond yogurt container solutions in private-, professional- and public environments. Furthermore, we design individual service packages concerned with the maintenance, health of plants and plant arrangements. From European studies we know that a better professional environment increases the motivation of people.     

Bildnachweis/Picture: GMH/FvRH

Common Sense

Green Team at Green Roof Technology, - Thursday, December 20, 2012

By: Jörg Breuning



Recently we have been receiving more and more calls regarding performance issues on extensive green roofs. Most of these roofs have been installed between 2-5 years ago by various green roof companies or supplied by different manufactures. Common complaints include dying plants, drainage system failure, growing media erosion and waterproofing leaks. Especially pre-vegetated systems (planters, trays, modules) mostly don’t meet expectations or even minimum requirements for green roofs. More often than not, green roof failures are the result of simple design or maintenance mistakes.

Many failures start within the design. A poor design leads to a snowballing effect of problems, growing and gaining velocity with every movement forward. Failures also occur during the construction phase when inexperienced installers claim a certain expertise because of a prior job, a way-back education or simply because they once watched a green roof installation. 

But problems can arise even sooner. We also noticed that many initial design and construction decisions are made ‘democratically’ or as a team consensus because no one person wants to carry the full responsibility on their own shoulders. Often these decisions are wrong and unrealistic. Physics, biology and chemistry are natural laws and cannot be compromised, even if done democratically.

Engineers must work within the parameters of reality and the best course of action is to always to use common sense.

In most cases things could be so easy if people would just use their own common sense and experience instead of believing all the nonsense they find on the internet.

Our commitment is to common sense, never nonsense. 



Ground Mounted Solar Farms - Questionable

Green Team at Green Roof Technology, - Saturday, December 08, 2012

Ground mounted Solar Farms are questionable.

Jörg Breuning Dec 5th 2012

 

It is widely known that multibillion companies are massively investing in solar energy. Especially Internet companies (Google, Yahoo, 1and1, etc.) have huge demands for energy to feed their decentralized server systems. Experts estimated that in ten years from now this modern telecommunication (internet, clouds, videos, email etc.) require worldwide 1963 Billion kWh. This is three times more than the current entire power consumption of France, Germany, Brazil and Canada together (Greenpeace).  With this numbers in mind it is understandable that these companies like to reduce their energy costs in the long run with alternative energies.

Photograph: Boris Horvat/AFP/Getty Images

However alternative energy doesn’t mean it is “green”. Especially ground mounted solar farms (the preferred solution of these companies) consume a tremendous amount of land and produce substantial amounts of run-off. Typically the development starts with clear-cuts of forests, elimination of native environments or transforming farm land. After the development is done sometimes vegetation is brought back. Typically low growing grasses that require regular maintenance with sheep, weed covers, mulch, gas powered mowers and chemicals.

Source: http://www.greentechmedia.com/content/images/articles/German-Solar-Weeds%281%29.jpg

Once this expensive maintenance is not done consistently the performance of the system will suffer and eventually completely fail.

Picture: http://www.greentechmedia.com/content/images/articles/German-Solar-Weedds(1).

 

Ground remote Solar Farms.

Solar arrays installed on already impervious areas will reduce the land consumption dramatically. Also being less addicted to Facebook , IGadgets, PC, or smart Phones can actually reduce the energy need -our impact- without losing contact to friends and still making new friends. A hand written note in a personal calendar can be more environmentally friendly than connecting to clouds and email programs.

Since there are already enough existing roofs, parking lots, rail road tracks and roadways that could be covered with Solar and also combined with extensive green roofs would create recognizable stormwater reduction, perviousness and last not least power. This combined technology is available since decades but many Architects, Engineers and developers seemed to be blinded by the sun while the supposing green industry takes out one piece of fertile land at a time and taking away nature’s most advanced solar panel – the plants that are surrounded by a natural sponge.

No additional land use and hardly any maintenance on extensive Green Roof / Solar combination with the well-engineered Sun-Root ™.


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