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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.

 

 

 

Green Roofs are Standard on Passive Houses

Green Team at Green Roof Technology, - Friday, June 14, 2013

By: Samantha Yurek


Photo Source: Wikipedia

In the past few decades sustainable building practices have come a long way. Many designers are striving to use the latest technologies to create more environmentally friendly conscience structures. Some of the best examples of sustainable buildings are considered Passive Houses. Germany is at the forefront of this trend, having been researching and developing specific environmental design principles since the early 1990s. These principles surpass LEED™ certifications and are overall less expensive. Energy consumption of a Passive House is between five to ten times lower than an average (LEED™) building, decreasing the environmental footprint two to five times. 

These houses are designed with many modifications. Exterior walls tend to be two to three times thicker when compared to conventional home. Natural and controlled ventilation systems are also prominent, helping to keep temperature balanced throughout the entire building. All these modifications make Passive Houses almost completely airtight and soundproof. Many of these houses are designed to include a green roof or solar powered system


Photo Source: Wikipedia - as you can see, this passive house on the right

In 2010, there were over 25,000 Passive Houses in Germany and around 13 in the United States. In Urbana, Illinois, the first Passive house was erected in America, back in 2003.

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

We Are Moving to Hampden

Green Team at Green Roof Technology, - Thursday, May 23, 2013

 

I am pleased to inform you that Green Roof Technology will be moving to a new location. On the corner of Roland Avenue and 37th Street in the heart of Hampden. We have acquired more space and a delightful location!

We will be relocating June 1st. Please feel free to stop by and check out the new place! Our phone and fax numbers will remain the same.

3646 Roland Avenue
Baltimore, MD 21211

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!

Green Roofs and Stormwater Fee

Green Team at Green Roof Technology, - Friday, May 17, 2013

Green Roofs Can Reduce Stormwater Runoff, Reduce Stormwater Fees!

By: Rebecca Gullott

Not many Marylanders are happy about paying the new stormwater fee or “rain tax” as it has come to be known. The county imposed fee is based on the amount of impervious surface such as rooftops and driveways on each property (cost-by-cause principle). In Howard County alone there are over 19,000 acres of impervious surfaces that contribute to pollution of local streams and the Chesapeake Bay. 19,000 acres are almost 30 sq miles or 11% of the counties size- more than double the size of all water ways in the county! No wonder that Stormwater runoff is responsible for over 20% of pollution into the bay.

Those wishing to lessen their stormwater fee can reduce the impervious surface area on their property through smart design and management practices. Howard County is providing instruction and incentives for citizens to do just that. Howard County Stormwater Management Division has partnered with several organizations including the University of Maryland Extension to help citizens take control of their environmental impact. Rainscaping workshops will be offered this summer to show residents how to plant and maintain rain gardens and native species; as well as compost waste and use rain barrels to collect roof runoff for use in lawn and garden irrigation or car washing. Howard County is offering free rain barrels at the Alpha Ridge Landfill select Saturdays April through September. Other Maryland Counties have similar programs so check your county’s website to see what offerings are available.

Property owners can receive credits for on-site improvements that reduce impervious surfaces. Whether it’s establishing a rain garden in the yard or incorporating planted areas or green roofs into the company’s parking lot, these incentives may encourage citizens to take control of their environmental impacts. These changes may help to reduce the need for future stormwater fee increases and promote a healthier Chesapeake for years to come.

The possitive impact for the environment by implementing cost-by-cause fess is very effective in many other counties and States in the US and over decades in Europe.

The Solar Boom

Green Team at Green Roof Technology, - Wednesday, May 08, 2013

By: Samantha Yurek

 
Photo Credit: The Solar Foundation

It is obvious the solar industry has been growing steadily, but an ongoing study by the Solar Foundation has uncovered to the extent in which the industry has expanded thus far. Solar workers now outnumber many of our larger occupations in the United States. Currently, we have more solar workers than coal miners in America, and the industry hasn't seized growth yet. The Solar Foundation released an interactive map naming the top three states with the most solar jobs as California, followed by Arizona and New Jersey. Most of these jobs are listed as installation positions, but others include manufacturing, project development, sales and distribution.

The new integrated Sun-Root™ System can help achieve both clean energy production along with additional benefits of a green roof. The Sun-Root™ System is the most advanced system solution that considers both enhanced water storage for the green roof plants and optimized evaporative cooling for solar panels.

 


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