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White Roofs are Better than Green Roofs!

Green Team at Green Roof Technology, - Friday, January 24, 2014

By Jörg Breuning

According a study from prestigious researches at LawrenceBerkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720, United States and School of Mechanical & Aerospace Engineering, Nanyang Technological University, Singapore, reflective roofs have a higher value for building owners than Green Roofs.

Julian Sproula, Man Pun Wanb, Benjamin H. Mandela and Arthur H. Rosenfeld developed a study that clearly explains the monetary benefits of reflective roofs v.s. Green Roofs v.s. traditional roofs. In their reductionist research, the outcome for green roofs is not good.  In a press release they stated:” The researchers acknowledge that their data are somewhat sparse but contend that their analysis is valuable in that it is the first to compare the economic costs and energy savings benefits of all three roof types.” It isn’t the first time – I have seen many worthless studies before…  

I am anchored in the Green Roof Industry since 1980, I roll my eyes and shake my head about counterproductive statements and studies like that. In the yellow pages they would have found somebody who could have told them differently and how to spend the generous money from the industry (other than green roof industry) much better – actually in building a Green Roof. Even when building a Green Roof doesn’t help the building owner (according their study) it would have helped the environment.

Bringing back nature into a location where nature was before is simply the best you can do!

My advice: Don’t start covering your Green Roofs or entire nature with a white piece of plastic – just don’t believe every written word on the internet or commercial reductionist research – Use your gut feeling and think out of the box!

This blog post represents the opinion of Jörg Breuning. If you have another opinion please feel free to contact me.  

Here is a link to the Study.


One Size Fits All

Green Team at Green Roof Technology, - Wednesday, October 30, 2013

By: Samantha Yurek

Or does it?  We're not talking about baseball caps or a pair of mittens here. Green roofs are a living system that on their own should thrive heartily in the environment in which they reside. Not all green roofs are similar, nor should they be. Diverse climates call for various approaches in construction a green roof to handle precipitation efficiently. The vegetation for any green roof should reflect local climate and growing conditions.

Uniform systems will most likely work out fine, but depending on the region, may need constant maintenance to uphold the health of the green roof. At this point, the question is if the green roof is actually doing its job. A green roof is supposed to thrive naturally, as a part of the ecosystem. It defeats the purpose when an irrigation system is put in place or the green roof is over maintained to avoid natural diversity.

Each green roof should be unique in a way that works most efficiently for that particular location. Here at Green Roof Technology we strive to create a living space that will thrive under specific conditions. There should be very little need for additional time, effort and money once a green roof has been put in place.

A Solar Garden Roof for Non-Profits

Green Team at Green Roof Technology, - Friday, June 21, 2013

By: Ryan Miller

Renewable energy is an attractive tool that businesses can use to offset rising energy costs. What makes renewable energy so attractive are the Federal and State incentives that cover over 30% of the costs to install the system. An investment today in a Solar Garden Roof creates a path of energy independence where your rooftop is producing the power necessary to run your building, instead of the local power plant.

So how does a non-taxable entity like a non-profit organization (NPO) take advantage of the plethora of incentives to produce energy for their own building? Fortunately there is an investment option tailored for NPO's called a Power Purchase Agreement (PPA). PPA's are used in situations where a site host does not desire to outlay the capital required to purchase a system, or is not able to take advantage of the tax benefits available due to being a non-tax paying entity. Through the PPA, the NPO will have no upfront investment nor carry any of the ongoing operations and maintenance obligations. The NPO will then enter into an agreement to purchase the energy produced at a rate below current energy rates.

With this setup, the NPO will make uniform, monthly payments at a reduced cost when compared to the current energy bill. After a set period of time, the NPO can decide to purchase the array from the investors at an agreed upon price. From there the system is paid off and the NPO is enjoying free energy, thanks to the SUN!

Green Roof Service/Green Roof Technology works with NPOs and investors to tailor the right PPA for an investment in a Solar Garden Roof.

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.

 

Lancaster Green Roofs Receive a Little More Green

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

By Andrew Yanders


E. King Fire Station after receiving 70 lbs. of Sedum Cuttings.  Five varieties of cuttings were spread that day and 6 varieties of   herbaceous plugs

Last week I traveled to the City of Lancaster to oversee the install of 155 lbs. of Sedum cuttings on the Dewatering Building and E. King Street Fire Station green roofs.  Both green roofs were installed earlier this year during the winter months.  The Dewatering green roof was installed January 22nd through the 25th and just under two months later Fire Station green roof was installed. 

There is a common misconception that green roofs cannot be constructed and vegetation planted during the winter months.  Actually, we believe installing green roofs when spring is just around the corner is ideal.   The weather may not be to the likely of many fair-weather green roofers, but for those who are willing to brace the cold and wet, the payback for the client is well worth it.  By establishing the vegetation in its new soil media prior to the start of the growing season, plants are able to jump start their growth and the first 2 months of the growing season can be equal to more than 6 months of growth if the same plants were planted later in the year.  Unfortunately, too often vegetation (in this case the Sedum cuttings) is not available until the spring when it is more advantageous for the nursery.

It was so cold the week we installed the Dewatering Building’s green roof that the growing media and Sedum mats arrived frozen solid.  The growing media had to be defrosted overnight inside the garage portion of the building and the Sedum mats that could not be unrolled were left out in the sun for one day.  Despite being completely frozen prior to install, the health of the Sedum mats was not compromised at all. 

There is one detail that must be given special attention when planting during the winter months.  When planting plugs, it is critical that they are planted as deep as possible.  If this requires loosening or removing a portion of the bottom, so be it.  But if they are not planted deep and the soil well compacted around them, then plugs will migrate up out of the soil during periods of freeze and thaw.  This can happen to the extent that a plug becomes completely removed from the soil, exposing the root system to the elements, and often results in the plug withering and dying.  Plugs are not cheap and a negligent planting technique is a waste of the client’s money. 

 

The color of the Sedum mats on the upper portion of the Dewatering Building's green roof has changed from mostly reds to a variety of lush greens.  New growth is abundant.  

Preparing the soil for Sedum cuttings is critical.  Because the soil was installed several weeks prior, the top layer of the soil needed to be loosens and leveled.  This increases the contact area between the soil and the cuttings, promoting more abundant rooting.

Even though there was a light rain while spreading the cuttings, we still watered the green roof.  We wanted to ensure there was uniform moisture throughout the roof, but also the moisture helps to hold the cuttings in place until they begin to root out in a few days.  

First Steps to Planning a Green Roof

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

 By: Samantha Yurek

Happy Earth Week! Hopefully everyone has taken some time out of their busy lives to lend a hand to our beautiful planet we inhabit. Whether it is picking up some litter, planting a tree or deciding to go all out and look into acquiring a green roof! Here are a few things you should have a good idea of before you leap into the planning process.

1. How sturdy is your roof?  Adding growing media and plants to your rooftop adds weight to your structure. Make sure your roof can handle some extra weight first. Find out the materials and structure of your building.

2. Is your roof sloped?  A slight slope is perfectly fine, but anything steeper than 15 degrees, the roof might become a slide for the plants without additional constructive design.

3. How much are you willing to spend?  Implementing a green roof is an investment for the future. Simple extensive vegetated roofs usually cost around $10-$15 a square foot (pre-grown planter boxes or modular systems are more expensive). Many local programs will help pay for green infrastructure, based on the environmental benefits. 

4. What type of green roof are you looking for?  A simple meadow-like area, not accessible and mainly for the environmental benefits (extensive) or an intensive roof, complete with recreational room and the potential for larger plants such as trees.

5. How are the sunlight conditions?  The majority of green roof plants enjoy direct sunlight to flourish. If the building is situated in a heavily shade area, the green roof plant selection becomes limited.

6. Do you want an integrated solar green roof?  The Sun-Root™ System is the newest of technologies, a fully integrated system and an ideal symbiosis of PV panels and an extensive green roof. It is easy to install and will not penetrate the roof. The entire system has the potential to pay back within 5 years and also meets stormwater requirements in all cities of North America.

 

Do your homework first before deciding on a green roof, our website is a great starting point to increase your green roof knowledge. If you're interested in a green roof or have any questions, please don't hesitate to contact us, we would be happy to help you get started today!

Stormwater Fee Looming Overhead

Green Team at Green Roof Technology, - Thursday, April 11, 2013

 By: Samantha Yurek


Photo Credit: The United States Geological Survey

The Chesapeake Bay is the heart of Maryland. Not only does it fuel our economy and recreational activities, with over 64,000 square miles it is home to over 2,700 different species of flora and fauna. It is an important resource that should be cared for adequately.

Excessive runoff is a huge culprit of transporting trash, chemicals, nutrients, along with other things that end up polluting the bay. With storm season lurking around the corner, Maryland is trying to prevent these mini flood events from polluting the Bay even more.  To mitigate for these rushing stormwater events, stormwater fees  will soon be added to everyone's quarterly water bill. There is no avoiding this fee that will essentially be paying for the impervious surface area one has on their property. Residential properties won't have such a heavy fine, but businesses may have to start paying a pretty penny. For example, take a look at any mall, the entire property is a combination of roof and blacktop.

The stormwater fee may be something you worry about, but there are ways to reduce the fees.  Planting trees, implementing rain gardens, and most importantly, adding vegetation to your rooftop are all proven ways to earn credits toward reducing the cost of the fees. Let's strive to keep Maryland beautiful; the Chesapeake Bay thanks you.


Photo Credit: Green Roof Technology

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”. 

Aquascape Sues over Collapsed Green Roof

Green Team at Green Roof Technology, - Thursday, March 07, 2013

 

By Jörg Breuning Picture: Daily Harrald

Back in February of 2011, the lower end of Aquascape's headquarters collapsed after a heavy snow event that blanketed Chicago with 2 feet of snow in 24 hours.  The building once held the title as the "largest sloping green roof in North America," covering over 256,000 square feet. 

In a blog post, Green Roof Technology covered the roof collapse back in 2011, blaming the failure of the green roof on poor engineering regarding the drainage of the system. Blog post 09/06/2011

We also wrote a Case study about the dilettantism and ignorance of so-called experts that are designers, engineers and construction companies when it comes to modern green roof technology (download PDF: Fixer Upper or Lawsuit? Sloped Extensive Green Roof Critique).

Since we've collected even more examples that are not mentioned in the press, that are fixed “quietly” or where the client has been convinced that certain problems are “normal” for a green roof. We estimate the potential of law suits on existing green roofs over 80 million Dollars, which is probably more than the entire Grant money  spent so far for the implementation of green roofs.   

Many of these self-promoted experts are still playing an important role in the American green roof education system (GRP) and within the North American industry. It is interesting to mention that in other countries where green roofs have been established over decades and where there are 10 times as many built annually, that there were never such incidents reported. These countries not even have a “highly developed” green roof professional education system. What they have is called Common Sense; the understanding of how small indicators could cause huge problems and they understand their responsibility to the industry even when they are not directly involved. There is no ignorance, dilettantism or vanity – just pure professionalism based on solid education.

Now two years later, Aquascape has sued 9 different contractors, construction companies, engineers and architects for $13 million in damages.  These companies include Artisan Design Build LLC, Senekteks, Tricon Construction, Olsson Roofing, Tecza Environmental Group, Applied Ecological Services, Metallic Building Company, Area Erectors and Dewberry Architects (Read the Daily Herald Article) and we still have the cart in front of the horse.

At Green Roof Service LLC/Green Roof Technology we obviously can't change the system, but we will continue to support owners of green roofs to get what they deserve and what they are paid for. 


Green Roofs & Solar: Double Your Benefits!

Green Team at Green Roof Technology, - Monday, March 04, 2013

Green Roofs & Walls of the World - Virtual Summit 2013 is striving to inform, share and create a global social media experience for learning and networking around green roofs and living walls.  

 

Join Jörg Breuning & Ryan Miller on Thursday March 7th at 1pm Eastern time as they discuss the benefits of combining solar power and vegetated roofs!

Immediately after Green Roof Technology's video, a 15 minute live Q&A will take place with Jörg and Ryan.  The video will touch on the benefits of a solar green roof, cost-benefit analysis, two interviews with the president of Solar Gaines, Hans Wittich and Artie Rollins, the assistant commissioner for city-wide services with the NYC Parks & Rec Building, along with much more. 

If you're interested, tune into the video and Q&A session, you may register on the Summit Website

 


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