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Cities Alive Annual Green Roof and Wall Conference

Green Team at Green Roof Technology, - Friday, September 27, 2013

October 23rd to the 26th San Francisco will be alive with Green Roof Professionals. Our very own Jörg Breuning will be featured in a lecture series at the Cities Alive Annual Green Roof and Wall Conference. The topic, Design with Maintenance in Mind, will highlight four sub-topics - one of which Jörg will be explaining the how the Solar Garden Roof System works, specifically highlighting the very first project installed on Randall's Island in New York City.

Reflective Surfaces on Buildings are an Environmental Nightmare!

Green Team at Green Roof Technology, - Monday, September 16, 2013

Reflective Surfaces on Buildings are an Environmental Nightmare!

 

A new building on London's skyline nicknamed the Walkie Talkie has been blamed for melted car parts due to the intense sunlight reflected from its glass exterior.  In a broadcast for Sky-News (movie) one reporter proves that it is possible to fry an egg in the reflected sunlight.  Developers say they are working to rectify the problem by coating the windows with a less reflective material.  The skyscraper's magnifying glass effect will continue for the next few weeks until the sun's elevation in the sky changes.  

 

Reflecting sun light from building reaches  up to 192°F ! Good to fry eggs.

While white roofs are not  typically curved and are less reflective than the glass clad skyscraper, the physics behind these surfaces are exactly the same. They both are designed to reflect a high amount of the sun light back to the atmosphere.  And by doing so, the reflected sun light has a second chance of being captured by particles in the air, increasing atmospheric temperatures surrounding the buildings.  Certainly London’s Walkie Talkie skyscraper is an extreme example due to the unique shape of the building.  However, it shows very clearly the physics of reflective surfaces, the damage they cause to the surrounding environment and a lot about the lack of common sense of architects, researchers and self-promoted experts.

With this last example, the discussion of high albedo building coverings (above Albedo 0,55) as being environmentally friendly should be at an end.  Governments (e.g. EPA, LEED) should ban reflective surfaces on buildings immediately if they are serious with their environmental programs.  Whether they were blinded by incomplete research, spoiled by the Dollars of manufacturers or simply think they can trick physics,  it does not matter at this point.

Green Roof and Greens Walls (with low albedo) are the better and most advanced choice - naturally.

Recommended: Cools roofs, cool façades are not cool – never have been.    

 

 

Protection for Honey Bees

Green Team at Green Roof Technology, - Friday, August 23, 2013

By: Samantha Yurek


Photo Credit: Demetrius Freeman - NY Times

Recently making an appearance on the front page of TIME Magazine honey bees are really starting to stir up popular interest.  But why all of the sudden? About a decade ago honey bees started dying off an alarming rates.  This past winter, nearly one third of honey bee colonies in the United States died or disappeared.  In June over 25,000 honey bees were found dead in a Target parking lot in Oregon.  Cause of death: an insecticide which contained neonicotinoids - a topic I covered back in May when the European Union took a stand and banned these killer pesticides.


  
 

Recognition of the significance of this issue is finally surfacing.  Although started back in 2009, National Honey Bee Day was a more popular holiday this year. A grassroots effort by beekeepers and interest groups to promote community awareness on honeybees, this holiday was celebrates this past Saturday August 17th.  The theme this year: "Beekeeping - Ask Me How to Get Started."  Farmer's markets and nature centers among others all over participated, educating the public on honey bees. 

All this commotion about these buzzing little creatures is beginning to pay off. The Environmental Protection Agency has ordered a reduction in the use of widely known pesticides and a change in labeling on pesticides to educate the consumer on the harm to certain pollinators.


Photo Credit: Jörg Breuning

Honey bee efforts have been popping up all over the country. These efforts have not only been seen on rural farms, but even on rooftops in the city! One example perched seven floors up, 100,000 honey bees buzz busily, hard at work to keep a Manhattan green roof flourishing. Green roofs are a great place to start an undisturbed honey bee colony. Let's not forget how important these little creatures are in our ecosystem and how essential they are to our food production. Take some time to learn more about the amazing honey bee!

Green Roof Technology doesn't allow the use of herbicides or pesticides on any green roof project since 1980!

Therapeutic Properties of Green Roofs

Green Team at Green Roof Technology, - Monday, August 19, 2013

By: Samantha Yurek


Situated on the 8th floor, this green roof is within view of
many of the hospital's rooms at Mercy Medical Center in Baltimore.

Flowering plants are a common sight spotting in any hospital wing, mainly attached with get well soon tags. The new trend seems to be green that will last more than a week or two. Many hospitals and health wellness buildings are incorporating green space, much of it making an appearance on the rooftops. Staring at an attractive green landscape rather than an unappealing tar-stained rooftop has the potential to make every patient calmer and happier on a daily basis. It has been proven that views of natural landscapes have a positive effect on the emotional and mental health of those being treated, as well as those visiting.

The Baltimore Sun recently published an article in their healing section titled, Garden Rx: Hospitals and homeowners alike are investing in the therapeutic properties of landscaped places. The article highlights the addition of healing gardens in well-known hospitals in Baltimore such as Mercy Medical Center, Baltimore Washington Medical Center, Kennedy Krieger Institute, Johns Hopkins Hospital and the UMD Rehabilitation and Orthopedic Institute.

Many of these healing gardens are designed to give patients, family and employees green space to relax and learn and heal within. The addition of green roof space provides many hospital rooms with preferred views of green plant life instead of a bland, brick building. Mercy Medical Center incorporated both healing gardens within a green roof, utilizing their space for both environmental and social benefits.

But not all patients can experience the benefits of an outdoor garden consequence of a compromised immune system. Months spent in the hospital battling leukemia created a unique opportunity for one SUNY-ESF landscape architecture student, Kevan Busa. Determined to graduate on time, but confined within the walls of a hospital, Kevan completed his final project on the healing potential of landscape design from a patient's perspective. Highlighted in the June 2013 issue of Landscape Architecture Magazine, Kevan explains the frustration of a poorly designed healing space. A visit to an outdoor garden is out of the question for many patients. Busa wrote, "the solution may be gardens that can be experienced from indoors, through glass. This idea may not sound terribly inviting, but it is a far preferable alternative to 100 days of brick walls."

Green roof space that can be viewed from individual hospital rooms could be the solution to a quicker healing time and happier patients.

A well-known hospital in Germany, Diakonie-Klinikum Stuttgart, has approximately 150,000 square feet of green roof along with indoor plants as large as trees. The greening of this hospital has been an ongoing process since 1990.

Urban Heat Island and Green Roofs

Green Team at Green Roof Technology, - Thursday, July 25, 2013

By: Samantha Yurek

With the heat index well into the triple digits lately, it is only appropriate to talk about the urban heat island. A metropolitan area which is significantly warmer than its rural counterparts, the urban heat island effect creates a more brutal environment, especially during these sweltering summer days.

Cities are dense and compact places. Most surface materials in urban spaces are good at absorbing heat, and have no means to transpire. Sunlight heats up these surfaces during the daytime, to temperatures higher than the air. In addition, impervious surfaces are prominent in city landscapes.

Many issues stem from the urban heat island effect, including increased energy consumption, resulting in elevated pollution emissions, compromising human health and comfort. Also, hotter surfaces create warmer runoff, endangering the local bodies of water; rapid temperature changes can be fatal for aquatic life.


Photo Credit: Dustin Phillips

Now we understand the urban heat island phenomenon, but is it easily resolved? 

Unfortunately with the amount of people residing in urban areas, the energy released will always be greater compared to rural areas. Although, there are ways to mitigate the hotter temperatures. In rural areas, temperatures are moderated through evapotranspiration, with vegetation being the main aid in cooler and healthier environments. According to the Environmental Protection Agency, "Trees, vegetation and green roofs can reduce heating and cooling energy use and associated air pollution and greenhouse gas emissions, remove air pollutants, sequester and store carbon, help lower the risk of heat-related illnesses and deaths, improve stormwater control and water quality, reduce noise levels, create habitats, improve aesthetic qualities, and increase property values."

By increasing vegetation in urban areas and the surrounding commercial belts in the form of street trees and green roofs, we can help create a cooler and healthier environment for ourselves. Not to mention a much more attractive landscape.

Herbicides in Green Roof Runoff Polluting Drinking Water

Green Team at Green Roof Technology, - Tuesday, July 23, 2013

The issue of root penetration is known to most in the green roofing industry.  The relatively complex world of roofing membrane compounds and organic chemistry has resulted in most green roof professionals defaulting to local instructional manuals, which default to FLL testing records.  But just because a material is effective does not mean it is not harmful, e.g. lead in paint.

In 1997, Bayer Aktiengesellschaft was the assignee of Patent US 5672568 A titled “Root growth inhibitors for building materials comprising monohydric alcohol esters of mecoprop.”   Root-resistant bitumen mixtures were soon marketed.

This past week the Berlin Senate’s Department for Urban Development and Environment and the Berlin State Office for Health and Social Affair published a series of recommendations for the prevention of environmental pollution due to the release of the herbicide Mecoprop from root-resistant bitumen membrane sheets. 

The statement reads:

Investigations at the Swiss Federal Institute for Water Resource and Conservation (EAWAG) on behalf of the Swiss Federal Office for the Environment (FOEN) have shown that Mecoprop under natural weather exposure is released from the bitumen sheets and the precipitate is washed out.

Rain water contaminated with Mecoprop can pollute combined sewers or surface waters.  Due to the low rate of elimination in sewage treatment plants results in a particularly high risk potential.  In a decentralized rainwater infiltration system there is a risk of soil and groundwater contamination.   (Translated from the German)

The report goes on to make simple recommendations.  The first says the use of bituminous membranes impregnated with Mecoprop should not be used unless absolutely necessary for structural reasons.  Second, they should never be used in protected water areas.

Since the issuance of Patent US 5672568 A, there has been a series of scientific papers published reporting the leaching of biocides from bitumen waterproofing.  They can be found here, here and here

Green Roof Technology is against any use of herbicides in green roof construction or maintenance.  For more information on how to protect your building against root penetration without the use of poisonous herbicides please contact our office.  

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 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

Green Roofs Don’t Work or People Don’t Work ?

Green Team at Green Roof Technology, - Wednesday, May 22, 2013

By: Jörg Breuning

 

Information spreads like wildfire in today's world; between the internet and numerous social media sites. It has become extremely easy to access relevant information anytime, anywhere. This is a fantastic technological advancement, with one weakness. Anyone can "publish" anything. 

Since the internet makes everything very easy to spread any kind of information around the globe in seconds, it seems that the quality of information provided to the public dropped at accordingly the same speed as it's distribution. Some people jump to conclusions; they are quick to talk and other are quick to responds via text and in most cases these are not the same people. I get the impression that one group is too lazy to write and the other group too lazy to think. They have a desperate need for attention - I like to call it Recognition Deficit or RD for short, which unfortunately results in misleading and false information to the reader. Many people in the audience often find it necessary to then add their own opinions and re-post the article, making things even worse.

An excellent example of RD was recently posted in the American Scientific. I believe this certainly affected their reputation in the scientific world and hopefully leads to better supervision of the people who have permission to post. Their article was copied and pasted onto numerous other websites, regardless of the comments left on the original page. In this instance, RD wasn't the only symptom, a combination of ignorance and laziness was also thrown into the mix.

Modern green roof technology is a well-established technology around the world. If some researchers think that there is room for improvements, they should consider previous research from around the world in addition to what might be sacrificed along the way. Focusing on one aspect of the issue won't work in a complex ecosystem. There are no defining traits of complex ecosystems, where Mother Nature undergoes consistent changes. Having a tunnel view sometimes helps, however we can't afford to lose the bird's-eye perspective of the decades of experience and hands-on professionals.

To all the skeptics out there, let's make a long story short:

Green Roofs do work, but many people don't!


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