Posts Tagged ‘Green Roof Construction and Maintenance’

Green Roof Construction-Structural Considerations

by KellyLuckett

October 7, 2010

Structural Support of the Green Roof

Excerpts from Green Roof Construction and Maintenance, by Kelly Luckett, 2009, published by McGraw-Hill’s GreenSource Books

Hi Green Roof Fans,

As one of the contributing editors here on Greenroofs.com – you may know me as “The Green Roof Guy” – I’m starting a series of excerpts from my book Green Roof Construction and Maintenance:

Rooftop Garden – Public Access
Having determined that the rooftop garden will be the place for people to gather and having provided access, one must ensure that the roof structure has the necessary structural capacity to support rooftop activity. Building codes may vary, so it is important to determine the local requirement for live loads and dead loads, and to understand how the green roof being built relates to weight requirement. The entire green roof assembly, including plants and the water required to saturate the growth media, is considered part of the dead load of the structure. Water in excess of that which saturates the growth media, snow and people visiting the green roof are all considered part of the live load of the structure. One must formulate a preliminary idea of what type of plants are desired and the proper growth media depth required to support them.

Saturated weight data should be available from the manufacturers of the intended green roof components. Typical rooftop gardens incorporate varying growth media depths and planters to support various plant choices. This will require calculations of the point loading of these various plant choices. Evaluating loading requirements and upgrading the structure to support the green roof is easiest and most economical in the design phase of the construction of the building. Evaluating the structural capacity and making upgrades to an existing structure is significantly more difficult and more expensive. Many retrofit green roof plans die at this stage due to inadequate structural capacity and the prohibitive cost of upgrades. While there are some creative strategies of employing irrigation systems to reduce growth media depths in order to reduce dead loading, live load requirements could mean abandoning public accessibility to the rooftop garden and opting to design a simpler, extensive roof.

Green roof – No public access
When the green roof will not be a public gathering space, the live load structural requirements for the green roof are less complicated. Once the load requirements of the local building code have been determined, one must calculate the saturated weight of the green roof system to determine if structural upgrades will be necessary. Again, this is going to require some idea of the type of plants intended to grow on the green roof and the growth media depth required to support them. Typically the entire green roof will have a uniform dead load based on the saturated weight of the green roof assembly, though one may considering positioning planters or mounded growth media over structural support members to incorporate some strategically located deeper growth media for larger showcase plants. The plant palette is significantly expanded by increasing the growth media depth. As increased depth results in increased weight, there are often trade offs that balance structural cost with plant selection. Once the dead load of the green roof has been determined, a new structure can be designed with the required capacity. For an existing structure, one must begin by determining the structural capacity and design within those parameters. Irrigation systems have been successfully used to reduce growth media depth, and thus weight of the green roof system, for projects that would have otherwise required costly structural upgrades. For example, the green roof on the Ford Rouge Dearborn Truck Plant thrives in less than 3 inches of growth media and is sustained during periods of drought by the strategic use of supplemental irrigation.

Make sure to read my column, and to learn more about my company, visit my website at: http://www.greenroofblocks.com/ or send me an email to: GreenRoofGuy@greenroofs.com.

Kelly Luckett, A/K/A The Green Roof Guy

LEED Credits and Green Roof Construction

by KellyLuckett

October 7, 2010

Excerpts from Green Roof Construction and Maintenance, by Kelly Luckett, 2009, published by Mcgraw-Hill’s GreenSource Books

Hi Green Roof Fans,

As one of the contributing editors here on Greenroofs.com – you may know me as “The Green Roof Guy” – I’m starting a series of excerpts from my book Green Roof Construction and Maintenance:

The United States Green Building Council (USGBC) has developed a rating system that awards designers and property owners with various levels of environmentally responsible building strategies.

The 69-point rating system is broken into five categories: Sustainable Sites (SS), Water Efficiency (WE), Energy and Atmosphere (EA), Materials and Resources (MR), and Indoor Environmental Quality (IE). There are five additional credits available for Innovative Design (ID). By taking prescriptive steps, the project team captures credits in the various categories to reach one of four levels of achievement: Certified, Silver, Gold, and Platinum.

For information on possible LEED credits associated with the use of specific green roof systems or components, contact the manufacturer.  If you’re using one of my Green Roof Blocks products, contact me by email. For more information on the USGBC or LEED, visit the USGBC website at www.USGBC.org.

The list of credits below can apply to construction of green roofs.

LEED Green Roof Possible Credits

SS 5.1
SS 6.1
SS7.2
WE 1.1 and 1.2
EA 1.1 to 1.10
MR 4.1 and 4.2
MR 5.1 and 5.2
ID 1.1 to 1.4

The full list is available on Page 142 of Green Roof Construction and Maintenance at Amazon.com.

Make sure to read my column, and to learn more about my company, visit my website at: http://www.greenroofblocks.com/ or send me an email to: GreenRoofGuy@greenroofs.com.

Kelly Luckett, A/K/A The Green Roof Guy

GPW: Forest Park Forever Playground, the Dennis & Judith Jones Variety Wonderland

by Linda Velazquez

April 2, 2010

 

Our GPW is the Dennis and Judith Jones Variety Wonderland, a delightful children’s playground in historic Forest Park, St. Louis, Missouri.  One of the largest urban parks in the United States, Forest Park opened in 1876 and is the former site of The World’s Fair of 1904, drawing more than 20 million visitors from around the world.  At 1,293 acres (5.2 km²), Forest Park is over 50% larger than New York’s Central Park (843 acres or 3.41 km²)!

Home to the region’s major cultural institutions—the Zoo, Art Museum, History Museum, Science Center and the Muny Opera, today Forest Park attracts more than 12 million visitors a year.  It also serves as a sports center for all kinds of activities and the park serves as a natural oasis for the city (see a Visitor’s Guide here).

The Dennis and Judith Jones Variety Wonderland is the City of St. Louis’ first inclusive public playground.  Designed in 2005 so that all children, able-bodied children and children with disabilities, could experience playtime together, it all began with feedback from a local organization: the Variety Family Council.  Now Variety, the Children’s Charity of St. Louis, they couldn’t find a public playground where their children with disabilities could play with their siblings – and so a saga was born.  Variety serves children with physical and mental disabilities in the region from infancy to the age of 21. Variety Week is April 17-24, 2010, and serves as a means to maximize awareness and fund-raising opportunities to benefit community children.

“We wanted this to be a place open to all children,” said Jan Albus, executive director of St. Louis Variety. “The most important thing was that it make it so children with disabilities could play right along with all other children.”

Three years, seven local donors, and a lot of hard work later, the $2 million state-of-the-art playground design includes 29 pieces of equipment on a soft, porous 10,100 sf surface.  The Dennis and Judith Jones Variety Wonderland playground is divided into five sections designed according to age, physical strength and abilities.

“First Adventures” is for children ages 2-5 and ”Big Adventures” for children ages 6 to 12.  Specialty areas are the “Observation Relaxation Deck,” “Living Shelter,” and the “Secret Garden.”  The Secret Garden contains 14 colorful perennials that attract, feed and house butterflies.  Learning stones will teach children about the life cycle of Monarchs here amidst the natural habitat.

Constructed to ADA standards for handicap accessibility, equipment includes a slide for children with cochlear implants, Braille and clock panels for the blind, talk phones, surface fountains and 8’ high ramping so children can experience a tree house affect.  You’ll also find a spyro slide, double slide, corkscrew climber, swings with bucket seats, spring pods, disc swing monkey bars with a vertical ladder, a pipe barrier with a steering wheel, and more.
 

This all-inclusive playground is located adjacent to the Dennis and Judith Jones Visitor and Education Center.  Formerly the Lindell Pavilion, it was built in 1892 as a shelter for streetcar passengers, and after a $4 million restoration, the facility is now home to Forest Park Forever, a not-for-profit organization dedicated to raising private funds for the restoration of Forest Park.

Kelly Luckett, LEED AP, GRP, and President of Green Roof Blocks (and one of our contributing editors, also known as “The Green Roof Guy“), was responsible for the lovely modular greenroof atop the walkway pavilion that connects from the Visitor and Education Center and greets children to the play area.  I asked him how he became involved with Forest Park Forever, and he replied:

“I did a lunch and learn for Powers Bowersox Associates, a St. Louis architectural firm.  After lunch, they showed me the preliminary sketches of the project and said they wanted to do a green roof on the structure so that it better fit into the green landscape of Forest Park.  They liked the portability of the modular concept that allowed us to pre-grow modules so the plants were more mature for the dedication ceremony.”

The roof is constructed of 60 mil reinforced EPDM fully adhered to poly-isocyanurate over metal deck, and 76 Green Roof Blocks were grown offsite at Jost Greenhouses for approximately 10 weeks allowing the plants to mature to 80% coverage at the time of installation.

Green Roof Blocks are low-maintenance, self contained, portable units consisting of a 24″ x 24″ module fabricated of heavy gauge anodized aluminum.  Walk pad material is fastened to the bottom, serving both to protect the roofing surface and to allow drainage under the Green Roof Blocks.  The walk pad material used is procured from the manufacturer of the building owner’s roofing system to insure compatibility and warranty integrity.

Powers Bowersox did not like the look of the sides of the aluminum modules and they requested Kelly to design a sheet metal trim piece that could be painted to match the edging of the roof, so a red metal skirt was installed at the Forest Park playground around the perimeter Blocks.

Remarkably, from a survival point of view (let alone plant diversity), the Green Roof Blocks were propagated with a single Sedum floriferum cultivar named ‘Weihenstephaner Gold,’ which performs beautifully in USDA Heat Zones 3-7.  Although quite luscious in its profusion of yellow and pink-hued summer blossoms (see above in flower from last spring 2009) as well as being and very effective and successful, it was the company’s last foray into a mono-crop green roof palette.  As current policy, Green Roof Blocks since uses multi-species for all projects.  Kelly explains:

“The plant species was selected for the evergreen characteristics, though we have since moved away from single species planting strategies for our green roof projects.  Only having one plant species planted on a green roof leaves the project vulnerable to weather anomalies or species specific pest that could affect the entire green roof.  We now plant at least five different species within each module.  This strategy establishes a diverse eco system more closely mimicking what we see in nature.  The plants on this project continue to thrive in part because the green roof plants have been included in the hundreds of thousands of plants that are under the constant watchful eye of the Forest Park Forever horticulturists.”

The growing media here is a 4″ deep blend of 80% red lava rock and 20% composted pine bark.  The plants were initially fertilized using Scotts Osmocote with a 12 to 14 month release.  Kelly says that each year since, he has picked up Vic (of Jost Greenhouses) and driven to each of their St. Louis green roof projects for maintenance and assessment.

“We give each one the spring feeding of slow release fertilizer, the plants get inspected by the trained eye of horticulturist Vic Jost, and I get a chance to get fresh photos of another year of plant growth.  We do not provide routine maintenance on our projects in other parts of the country.  Our St. Louis customers find this added perk to be a nice touch,”  Kelly Luckett adds.

Kelly says he is pleased that some stakeholders even make it a point to be present so they can discuss the project with Vic and himself, and looks forward to their maintenance visit each year.  So for almost five years, this simple vegetated roof has not only survived with minimal maintenance, by all accounts it has flourished quite nicely.

Aramis and I had the opportunity to visit the stunning Park Forest grounds and this beautiful playground in late June of 2006 when I was invited by Dr. Bill Retzlaff of Southern Illinois University-Edwardsville, IL (SIUE) and Kelly Luckett to speak at the SIUe Green Roof Symposium.  By the way, Kelly is also the author of “Green Roof Construction and Maintenance” (GreenSource Books), 2009 from The McGraw-Hill Companies, Inc. - a great resource, full of detailed, useful information for all of us.

Kelly and his wife Trish played wonderful hosts to us and showed off their lovely city by highlighting the Forest Park Forever playground, where I found a very cool drinking fountain feature, above, and also taking us to many attractions – the iconic image of St. Louis - the Gateway Arch, a Cardinals baseball game, and the awesome and sometimes surreal glass-blown designs of Dale Chihuly at the Missouri Botanical Gardens “Glass in the Garden” exhibition, below.

Forest Park is really a midwestern gem – a peaceful place to relax and reflect in a lush, green space filled with water, trees and sky.  As we all know, playtime is one of the strongest teachers and in such a fun and accessible environment, children will learn naturally about various forms of diversity, disability and acceptance while developing increased strength, coordination, confidence and social skills.

I had the pleasure of seeing kids of all ages and abilities benefit while playing in this charming and educational wonderland, and I sure had a good time, too!

An important urban oasis of green within metro St. Louis, Forest Park offers a respite for migrating birds and butterflies, and an integrated ecosystem where humans and nature interact – especially on one albeitly small playground and its simple greenroof.

~ Linda V.