Green Team at Green Roof Technology, - Wednesday, April 18, 2012
By Kat Harrold
Photo ~ By Green Roof Technology
For some, green roofs may seem a novel addition to a green minded institution but to Swarthmore College it was an essential and strategic move. In 2008 when the college needed to add a dormitory to accommodate its growing student body, there were concerns about the increased run off from the new construction. Sustainable architecture through green roofs offered a solution that minimized the building foot print making construction of the new dorm possible. The green roof was spear headed by a few brave faculty, dedicated alumni and students, and Green Roof Technology. To stay on budget the school chose to invest in a green roof instead of the costly LEED certificate while still building to LEED standards. This dorm was recognized in 2010 with the American Institute of Architects Housing Award.
The 8,600 sf green roof is the home to many plant species including sedum album murale, sedum spurieum roseum, delosperma nubigerum, and some indigenous plantings. The green roof also features a raised planting bed for experimental vegetation such as cacti.
The profile of the green roof is a shallow extensive system and has a total profile of 3.5 inches with the growing media depth composed of 2 inches. While Swarthmore may have a reputation for having the best maintained green roofs in the area, the maintenance required on the roof is blissfully minimal. To maintain its pristine state Gardener Lars Rasmussen weeds occasionally as needed and irrigates only when drought conditions exceed two weeks. The roof is minimally fertilized and occasionally cutting back of the overly aggressive plants takes place to encourage more diversity on the roof.
Since its installation the green roof has reduced run off, air pollution, and saved energy on the top floor of the building by as much as 25%. While the green roof is not available for students to congregate it is open for guided tours and classes and is visible to all from the third floor.
Green Team at Green Roof Technology, - Thursday, April 12, 2012
By Kat Harrold
Photo By Jorg Breuning
Mulching season is upon us the air is ripe it's fragrance. While the good gardener may protect their garden from unwanted weeds with a coat of mulch this can actually kill the functionality of a green roof.
The fine organic matter produced from the decaying mulch creates a hotbed for weeds that take advantage of the added nutrients. These same fine particles also clog the filter fabric and drains which result and standing water and roof load issues.
To protect your green roof from unwanted plants there are two main things you can do. The first is if it is a sedum roof, don't irrigate unless extreme drought lasting more than a month. The dry conditions often fry the seeds before they get a chance to germinate. Use only a small amount of slow release fertilizer twice a year for the first 4 years. Poor soils with a low level of nutrients are ideal for sedums. Excessive fertilizer can actually be detrimental to sedum growth while simultaneously providing excellent conditions for weed growth.
Green Team at Green Roof Technology, - Tuesday, April 10, 2012
By Kat Harrold
Photo ~ Kat Harrold
For those of you looking to escape the cold snap and visit the warm weather again try the NYC Botanical Orchid Show. Not only will you get your warm weather fix but you will also be privy to an incredible display of living art featuring vertical gardens by french botanist Patrick Blanc.
The show runs till the end of the month and features orchids of every color, shape, and species imaginable. As an avid orchid fan I have spent countless hours admiring the orchid displays of Longwood Gardens and this might even trump their Orchid Extravaganza. What makes this particular orchid display so amazing is the integration of so many varieties into several Patric Blanc designed green walls.
Like an artist carefully apply strokes of paint to a canvas, Patrick Blanc give sweeps of color to these green walls with dedrobiums, cymbidiums, cattelyas, and many more. The use of ephiphytes, plants that absorb moisture and nutrients from the air or accumulating debris, are an excellent choice for maximizing water and nutrient resource conservation in green walls.
Green Team at Green Roof Technology, - Wednesday, April 04, 2012
By Kat Harrold
Photo~ Jorg Breuning
It's official! The 'Sun-Roots' have landed in America! The first installation of 'Sun-Roots' took place on the NYC Department of Parks and Recreation at Randall's Island. The 'Sun-Roots' are part of their on going green roof research program that tests over 25 different green roof systems.
Check back soon for more information on this revolutionary system pending the installation of it's solar panels!
Green Team at Green Roof Technology, - Wednesday, March 28, 2012
By Kat Harrold
Photo ~ Green Roof Technology
In 1988 fire research testing on green roofs was begun by the Research and Material Testing laboratory of Baden-Wurttemberg in Stuttgart Germany. Initial testing began with the evaluation of bituminous waterproofing layers. It was discovered that the bituminous waterproofing when burned produced 50 kWh/m2. Alternatively when this burn test was done on an extensive green roof with dry grasses only 3 kWh/m2 were produced.
Tests were then done to see if it was possible to establish a fire that would spread across an extensive green roof and or start a glowing/burning of the growing media. After several tests the conclusion was made that it was nearly impossible to create a fire on an extensive green roof that would spread across the roof or ignite the growing media. Conversely it was discovered that a bare regular bituminous waterproofing membrane was 15-20 times more likely to catch fire than an extensive green roof with grasses and perennials. It is for these reasons that many Germany insurance companies offer a 10-20% discount on fire insurance when a building has a built in place green roof.
On large extensive green roofs with grasses where there is a concern of fire spreading by wind carried sparks, spreading can be reduced or contained by use of fire breaks in the form of vegetation free strips. These vegetation free strips can measure approximate 3 feet wide and be composed of river rock or gravel. Vegetation free zones around roof hatch openings and other roof penetrations can also reduce harm to the building.
For more information on Fire and Wind on Extensive Green Roofs visit our resources page
for a downloadable report.
Fire Tests in Germany Picture By: Universität Paffenwald
Green Team at Green Roof Technology, - Monday, March 26, 2012
By Joe Devoy ~Tellus 360
Photos by Tellus 360
A year has passed since the Tellus 360’s green roof was installed and we caught up with Tellus 360’s owner, Joe Devoy. We asked Joe to write a few words reflecting on his new urban oasis.
“One day we were standing on our big flat roof, the sun shining down, the wind gently blowing, having a chat. We were looking at the Marriott and Convention Center being built next door. Coming up to the roof had become a kind of ritual, a pleasant place to relax and reflect.
When we were on the roof we were still part of the city, but it was a different part of the city. Captured all around us were the sounds of city but we were still removed somehow. After a few of these trips the decision was made; a green roof must be built on our roof. We all needed a therapeutic place where city and nature could meet, where the sounds of life relax not excite.
As we talked to Fritz Schroeder of LIVE Green Lancaster and met Jörg and Kat from Green Roof Technology, our vision of a community oasis developed in our mind. “A better way to live and a better life for our building.” Our vision for our building has always been for it to be alive, that it could breathe with the city. We want it to expand and contract, to participate in our life and to help us be better in the way we live.
Our new green roof has achieved that and the life it has brought to our building and our community has been equally amazing. Now I return each morning for my daily ritual. The smell of earth and the sounds of a city alive surround me as I enjoy my breakfast from the local farmers market. I love to hear the city breathe, I love to hear our building breathe.”
Green Team at Green Roof Technology, - Monday, March 12, 2012
By Kat Harrold
Photo Courtesy of Optigrun
Next week the New York City Parks Department will be adding a landmark addition to their green roof research facility. The NYC Parks Department oversees the largest know US green roof systems test facility and will be adding the Sun-Root solar living roof to their collection.
Located on Randall's Island, the Parks Department Five Borough Administrative Building houses over 29,000 square feet of test green roofs making the collection the 5th largest green roof in New York City. The outdoor laboratory features over 25 different systems of various growing media depths. Weather stations and temperature sensors minor the conditions on the systems and update findings every 15 minutes on their website for public comparison.
Green Team at Green Roof Technology, - Thursday, March 08, 2012
By Kat Harrold
Photo by ~ Goldtex
Where square footage is at a premium the demand for green space has become one of the hottest commodities. In a high rise apartment building one might consider the options quite limited. Try thinking outside the box, literally, and imagine all the vertical space available. Where horizontal space is limited vertical gardens offer a green oasis in a concrete jungle.
With the right plant selection outdoor green walls make wonderful neighbors. A green wall composed of hardy vines can provide seasonal interest with an array of colorful leaves and fragrant blossoms. Plant selection can also play an important role in attracting birds and pollinating insects.
In spite of their good looks, climbing green walls can be low maintenance requiring only occasional pruning and irrigation depending on location. Steel cables and wire-mesh grids can be used to support and train climbing vegetation.
Green walls can play an important role in energy savings. By shading the building during the summer and providing insulation in the winter, green walls reduce seasonal stresses on heating and cooling. The ideal location for a green wall to reduce summer cooling costs is the south facing side of the building. The southern exposure receives the most sun light which can also be very beneficial to the vines.
Green Team at Green Roof Technology, - Tuesday, March 06, 2012
By Kat Harrold
Photos By Jorg Breuning
The Royal Caribbean Cruise line Lawn Club exemplifies the very finest in green roof design and engineering, providing the exquisite presentation and luxury Royal Caribbean guests have come to expect. The apply named Lawn Club is featured on cruise liners Solstice, Eclipse, Equinox, and Silhouette. In addition to lawn games such as bocce, golf, and croquet, some of lawn clubs also features a hot glass show, cook to order grill, and lounge.
Normally, a lawn of this caliber requires a soil depth of at least a foot. Due to weight restrictions, a modified green roof system with subsurface irrigation was engineered to provide a light weight solution with a 5 inch profile. A surface irrigation system with hand watering is also employed to flush excess salts from the lawn. All run off from the system is collected and treated on the ship.
A specially selected grass mix allows the lawn to remain lush and green despite stress from salt, changes in latitude, and foot traffic. A team of highly experienced golf course specialists are on staff to ensure 24 hour monitoring and the health of the lawn.
The Lawn Club has been such a huge success Royal Caribbean will be adding yet another Lawn Club to their latest ship scheduled for completion at the end of 2012.
Green Team at Green Roof Technology, - Friday, March 02, 2012
By Kat Harrold
Photos by ~ Kat Harrold
Sedums may be great for the hot dry climate of the green roof there are more colorful accent plants to consider such as bulbs.
Early spring when sedum album is just starting to wake from its winter’s nap Snow drops (Galanthus nivalis) spring forth with their deep green foliage and delicate white flowers.
Other excellent spring bulb choices are dwarf iris, crocus, daffodils, tulips, and chionodaxa. As the seasons progress, splashes of color can be added to the roof with bulbs such as allium and cyclamen in summer and early autumn.
Many of these bulbs are native to the harsh environments of the middle east and western Asia making them perfect candidates for the green roof environment.
The general rule of thumb when planting bulbs on a green roof is to cover the bulb with 3 times with the amount of growing media as its height with the crown facing upwards. In other words if you have a 1 inch tall bulb you want to cover it with 3 inches of growing media. Therefore, larger bulbs will have greater success in deeper green roofs with a 4 inch or greater growing media depth.