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Sky Gardens ~
Travels in Landscape Architecture

By Linda S. Velazquez, ASLA Associate, Publisher

August/September 2004 ~ updated 8.22.04

Washington State Flag, U.S.A.

Seattle and Washington State, U.S.A.
Spectacular views of the Port of Seattle greet visitors on Puget Sound, located 113 miles (182 km) from the U.S.-Canadian border.  From the histories of the Duwamish, Suquamish, and Lushootseed tribes – among others - to the fur and logging trades to Boeing, Microsoft, Starbucks, and even the Grunge movement, the City of Seattle has evolved into a commercial, cultural and advanced technology hub of the U.S. Pacific Northwest and a major port city for trans-Pacific and European trade.

"Surround Yourself in the Rugged Beauty of the North Cascades"

The Skagit River, Washington State

Named after Chief Seattle (Si'a) of intertribal nobility, the City of Seattle was founded in 1869. Surrounded by mountains and water, the greater Seattle area features picture-perfect views and abundant recreational opportunities year-round.  And Washington State’s pristine lakes and waterways, rugged trails, majestic peaks and valleys, volcanoes, and campgrounds are renowned for their breathtaking scenic splendor.  See the award-winning streaming video, Surround Yourself in the Rugged Beauty of the North Cascades on the Skagit River by Seattle City Lights, the electricity company.

From whale watching to Mount Rainier, the Puget Sound offers many tourist opportunities among the performing arts, eclectic music scenes, sports, parks, museums, breweries, coffee and art houses and more.

Yet, the Port of Seattle, the Space Needle with the 360º observation deck (now forever associated with Frasier), the Seattle Aquarium, and so much more are also certainly worthy attractions.  You can Request a Seattle Visitor Information Packet from Seattle’s Convention and Visitors Bureau.

In my flying career, I’ve spent many an afternoon strolling through Seattle's eclectic Pioneer Square district, taking a ferry over to various area islands enjoying art enclaves, and of course, wandering along the Pike Place Market, ducking the flying fish, and eating my way through the hustle and bustle of tourists, shoppers, and buyers of fresh local fish, seafood and farm produce.

In fact, the official site of the City of Seattle states “The Pike Place Market is the soul of Seattle.  The Market's traditions, products, and people create a unique shopping destination and a thriving community.”  And I wholeheartedly agree that this lively, colorful, and decidedly unique public market deserves a visit if nothing else but for people watching, eating and taking in the sights, smells and sounds of fish being thrown across stalls, strolling musicians, fragrant fruits and flowers and simmering culinary delights.

An Eco-friendly and High Performance Attitude

The Pacific Northwest in general is known for eco-friendly, sustainable building policies, high-performance green architecture, and local innovative building designs.  For example, the new Seattle Art Museum is restoring their heavily polluted site previously owned by Unocal, a petroleum-contaminated locale which housed pipes and oil tanks. In its place on the Belltown waterfront $85 million Olympic Sculpture Park.  According to the June 25 article in the Seattle Post-Intelligencer, "The sculpture park isn't the first local conversion of a polluted site into a home for art. The Museum of Glass in Tacoma is built along the Thea Foss Waterway, which is part of a massive cleanup of Commencement Bay."

Other prime examples of Washington state ecological design and landscape architecture can be found at Gold LEED™ certified IslandWood, AKA The Puget Sound Environmental Learning Center, in Bainbridge Island, by Mithun.  IslandWood is an environmental education center which was carefully sited based on the natural resources of the site.  It includes a living machine, a straw bale studio, stormwater cisterns, photovoltaics, recycled materials and art installations.  Nordheim Court is a student housing project for the University of Washington that establishes an urban setting around an existing pond habitat and porous concrete paving is used around the pond and two art installations by Dan Corson interpret the pond ecology.  And Seattle Housing Authority’s High Point is an urban redevelopment project under construction in West Seattle. The new community is a Hope VI project incorporating market rate and rental units.  A natural drainage system of streets and open space is designed to treat stormwater flow and reduce impacts on Longfellow Creek, one of the City’s priority salmon bearing creeks.  The first phase is scheduled to open in Spring 2005.

An example of the area's ecologically friendly non-profit organizations is Earth Share of Washington - a network of 65 leading environmental organizations that helps to protect the environment and quality of life - locally, nationally and internationally.

And specifically, the Seattle area has developed stringent codes and regulations intended to protect the environment and promote resource efficiency, and so it is no surprise that they are one of the nation's leaders within the green design field.  For example, Seattle imposes: a more stringent energy code than ASHRAE/IESNA Standard 90.1-1999; prohibitions on single-pass HVAC cooling; environmental tobacco smoke control requirements; policies encouraging low-emitting adhesives, sealants, paints, and carpet systems; carpool preference policies; and recycling area requirements.

Yet, like the majority of the U.S., the Pacific Northwest is no stranger to development problems.  A 2003 study by the Seattle Post-Intelligencer revealed that the stormwater runoff pollutants accumulated from vehicles, lawns, rooftops, and other surfaces contaminate one-third of Washington's water bodies, and these do not meet the standards of the nation's Clean Water Act.  Vegetated swales and rain gardens are some of the low-impact measures being implemented, and innovative building design, including greenroofs, are being incorporated within the municipal fabric.

First U.S. City Government Committed to Silver LEED™ Facilities

Indeed, in 2000, the City of Seattle adopted its Sustainable Building Policy requiring new city buildings to attain a Silver LEED (Leadership in Energy and Environmental Design Green Building Rating System) certification rating.  City departments were instructed to design and construct both new and renovated City facilities greater than 5,000 square feet so that they achieve a Silver LEED rating.  The City’s Office of Sustainability and Environment (SOSE) is responsible for overseeing implementation of this policy.

Seattle Sustainable Building Incentives and Certification Programs

The 2004 BUILT GREEN™ Incentive Program (PDF): "The City of Seattle wants private sector construction projects to follow its lead by incorporating more sustainable, “green” materials and methods.  Funded by Seattle City Light and Seattle Public Utilities, the BUILT GREEN™ Incentive Program provides financial assistance to building owners and developers to incorporate meaningful and cost-effective sustainable building goals early in building programming and design decisions.  The City will be an active observer, to help develop other cost effective sustainable building services that the City can offer to the private sector."  Multi-family projects of five units or more that meet the criteria described in the Built Green™ Multi-Family Checklist or Built Green™ Communities Checklist are eligible, but funding is limited.  Projects selected for funding will be those that most aggressively comply with the criteria detailed in the BUILT GREEN™ Incentive Pre-Application form.

Following similar guidelines and philosophies, the 2004 LEED™ Incentive Program (PDF) is funded by Seattle City Light and Seattle Public Utilities and makes available to building owners and developers, on an optional basis: technical assistance from the City's Green Building Team, the Lighting Design Lab and the Resource Venture; facilitation assistance for up to two Building Design Charettes; assistance in maximizing the value of Seattle City Light Energy Smart Design Incentives or Seattle City Light Built Smart Incentives and Seattle Public Utilities Water Smart Technology Incentives and technical assistance.

This incentive program pertains to new construction or major remodels that meet the criteria described in LEED™ 2.1, or LEED™ Pilot programs – LEED™ EB, LEED™ CI, or new LEED™ pilots as they are introduced.  Read more about Seattle's LEED™ Incentive Program here.  For more information, contact City Light's Sustainable Building Coordinator, Peter Dobrovolny at 206.615.1094.

Click here to read the April 2003 report prepared by SBW Consulting, Inc., entitled "Achieving Silver LEED: Preliminary Benefit-Cost Analysis for Two City of Seattle Facilities Report No. 0303" for the Seattle Office of Sustainability and Environment.  According to the Report, "The purpose of this study was to evaluate the impacts of the Sustainable Building Policy on two projects nearing completion in early 2003: the Seattle Justice Center and Marion Oliver McCaw Performance Hall."  Specifically regarding the Seattle Justice Center greenroof, the Report concludes, "Some of the major actions that LEED influenced include the west-facing buffer wall, light shelves, and Green roof..."  Overall, the Report concluded that when examined over a 25-year period "for the two studied projects combined, LEED-influenced actions are cost-effective."

According to Resource Venture, "Sustainable building assistance is available to Seattle-based design and construction professionals or to any projects located in Seattle."  Many other types of private and public financial incentives and assistance programs are available to Seattle building projects, and this is an extremely informative resource for the area, and a site to be explored.

Aside from LEED™, various local voluntary standards are programs are available to  promote and assist designers and developers such as BuiltGreen™, BuiltSmart, and  Construction Works.

Other Seattle Market Drivers and Early Greenroof Leaders

Similar geography and natural resources connect and relate the area to Portland, OR, forcing Seattle to also deal with the combined sewage overflows that contaminate local waterways with tons of untreated sewage during periods of heavy rain.  Aside from stormwater's erosion effects, valuable fish populations and other aquatic organisms are threatened from the resulting pollutants and warmer water temperatures.  Just one other ecological driving factor for the promotion of modern greenroofs.  Restoring natural cycles - especially the water cycle - is one of things an ecoroof is all about.

Early intensive greenroof projects include Freeway Park by Lawrence Halprin, constructed in 1972 - 1976 and West Point Sewage Treatment Plant by Angela Danadjieva in 1996, and the Convention Center.  Earth-sheltered homes were popular in the 70's but extensive greenroofs, or ecoroofs as they are also know here, have been around since the early 1990's like most areas of North America.

Cedar River Watershed Education Center Greenroof

Cedar River Watershed Education Center greenroof in Seattle, WA; Photo by hadj design.

The Cedar River Watershed Education Center in Cedar Falls, WA, by Jones and Jones Architects and Landscape Architects is credited to be the really first extensive type system installed in the area - see the case study below.

Everyone I spoke with credits several individuals - architects, landscape architects, various government people - as early ecoroof promoters.  Lucia Athens, City of Seattle Public Utilities sustainable building coordinator, and Lynne Barker at Department of Planning and Development have been promoting greenroofs and sustainable development for many years in this region.  Johnpaul Jones, Paul Olson, and Nancy Rottle of Jones & Jones - among others - also have been involved and are credited with projects promoting green roofs for widespread residential application.

Nancy Rottle shares, "We really didn't hear about them (greenroofs) until the 90's - even the words "intensive" and "extensive" weren't used much until towards the end of the decade.  I think the NW EcoBuilding Guild was instrumental in bringing precedent research that identified the intensive/extensive typology and terminology to the fore, and promoting the extensive type.  There were several buildings on the islands of British Columbia constructed by the early 90's - a community center on Denman Island comes to mind.  A very early sod roof - I suppose it would be considered an extensive roof - was built by Paul Thiry, a well-respected Pacific Northwest architect, on one of the San Juan Islands in Washington, probably in the 50's."  Publisher's Note:  We will try and get more precise references about these structures.

However, Washington state stands out from the rest of the U.S. and certainly all of North America in that it has an unusually high number of residential applications.  In particular Patrick Carey, principal of hadj design, and director of The Northwest EcoBuilding Guild's Green Roof Project, is a visionary designer committed to affordable sustainable design and must be recognized with jump starting the residential greenroof movement here.

The Northwest EcoBuilding Guild and hadj design

The Northwest Eco-Building Guild is the Pacific Northwest’s leading ecological building association whose members include builders, designers, homeowners, trades people, manufacturers, suppliers and others interested in sustainable building.  Founded in 1993 by a small group of people who were already incorporating green building ideas into their practices, they formed the Guild for the purpose of networking and exchanging areas of expertise.  Since then, the Guild has grown to seven chapters around the northwest.  A vital organization, its mission is to function as an educational forum to facilitate building practices that protect human health; encourage sustainable resource usage; and foster long-term economic vitality.  Most of the Guild's Green Roof Project green roofs vary in at least three aspects of assembly components, microclimatic conditions, slope and scale of roof, plant and growth media selection.

Patrick Carey is extremely dedicated to designing a better greenroof mousetrap for the residential market, and is quite passionate on the subject, and some could even say rather outspoken concerning the current state of greenroof affairs. “You’re reforesting the built environment,” says Patrick.  “There’s something so symbolic about that.  Green roofs make a statement about ecology that no other building feature can.”  The Northwest EcoBuilding Guild has designed and installed 20 greenroofs to date on residential carports, garages and studios, and hadj design will design and install between 10 and 12 more projects this year.

"By our count this total will represent about one half of all the residential green roofs in the Pacific Northwest, which covers Oregon, Washington, and British Columbia," Patrick continues.  "There are some qualifications to this data.  For instance, is it considered a residential green roof if a client simply puts a commercial system on their house?  Is it a residential green roof if it is not over living space, or a chicken coop or a dog house?
"Our standard is that if a green roof in assembly and detail can be successfully be replicated on a residential structure, then it is a residential green roof.  So, for instance, if the framing, assembly, detailing, planting, etc.. of a 50 sf chicken coop can be expanded to accommodate a house without changing any of its elements, then it is a residential green roof.  If I take the identical system I use for a commercial building and simply replicate it on a house, I still call it a commercial green roof because the cost, assembly, and installation are still primarily commercial in nature. In other words, if I am rich enough to put a commercial system on my house, I can't - by virtue of my wealth - call it a residential green roof.  Such a roof could never get wide spread application in the residential community. This is my litmus test."

Ecoroofs in Seattle

I visited Seattle a couple of weeks ago, and enjoyed a beautiful day of moderate temperature in the high 70's, low humidity, and a wonderful breeze (the very opposite of "Hotlanta!").  Patrick Carey was my host, and he graciously took me across the city to visit nine area greenroofs.

Washington State Government Greenroofs

Our first tour included the following two City greenroofs, and we were met by Jackie Campbell, Property Manager, Fleets and Facilities Department of the City of Seattle, who took us on a personal visit of these beautiful new buildings across the street from each other:

Photo by LSV

Seattle City Hall in July, 2004.  Photo by Linda S. Velazquez.

Seattle City Hall -  Completed in 2003, Seattle City Hall is the result of a design team including architects, artists, landscape architects and engineers, led by the joint venture Bassetti Architects/Bohlin Cywinski Jackson.  Green strategies include rain-water harvesting, an under-floor HVAC system, and a greenroof.

The greenroof and major portions of Seattle City Hall were completed in 2004, and as you can see by the photos, additional construction continues today.

Seattle City Hall is part of a three-block area known as the Seattle Civic Center, and is expected to meet or exceed Silver LEED certification.  The greenroof is not accessible, but can be viewed from the elevator lobbies on floors 3 through 7.  On the day Patrick and I visited we saw butterflies and bees among the flowers and grasses, and were told birds were often spied as well.  See the City Case Study here, and see the project Profile in The Greenroof Projects Database here

In an effort to get a better perspective, these photos below were taken across the street from the Seattle City Hall in an abandoned public building currently being used by the FBI, SWAT, and other local police training entities  -  quite an adventure visiting in itself:

Photo by LSV Photo by LSV

Different vantage points of the Seattle City Hall Greenroof on July 19, 2004.  Photos by LSV.


SJC Model by NBBJ Architects
Model of Seattle Justice Center by NBBJ Architects

The Seattle Justice Center -  Completed in the fall of 2002, the Seattle Justice Center Silver LEED certified building is located adjacent to the Key Tower, Bank America Building and Seattle City Hall. The 12th floor roof atop the Justice Center has a prominent place in the surrounding cityscape.  Potential jurors from the jury assembly room and occupants of neighboring hi-rise buildings will be able to view the roofscape, so an attractive view was very important to the design team.

Lucia Athens at Seattle Public Utilities was part of the effort to incorporate monitoring into this green roof.  The architect of record is NBBJ Architects, the greenroof system used is from American Hydrotech, and the greenroof designers were Robin Laughlin and Matt Suhadolnik, landscape architects from SvR design company.  The designers decided upon 6" of growth media and low growing hardy plants to conform with the low maintenance requirements.

Some green palnts and brown plants!

Seattle Justice Center Greenroof on July 19, 2004.  Photo by LSV.

Seattle Justice Center waiting to be planted

Planting day October 10, 2002. Source: Mayor Greg Nickels' Photo Gallery

The Seattle Justice Center greenroof achieved LEED points in the categories of Sustainable Sites - Protection or Restoration of Open Space; Stormwater Management; and Landscape/exterior design to reduce heat islands (roof); and Water Efficiency - Water Efficient landscaping.

Jackie Campbell tells me that many of the plants will soon be replaced with a mixture of more drought tolerant natives and naturalized species such as lavenders, and more common succulent greenroof plants.  An usually high failure rate was perhaps due to the fact that the greenroof was not initially irrigated regularly to get the plants established, and was retrofitted with drip irrigation after the fact - too late in the game.  The plants doing the best on my visit were the Sedum album, Carex glauca, and the strawberry plants.  Read the project profile in The Greenroof Projects Database here.

In any case, the 12th floor outdoor area is a very spacious and accommodating location available to visitors and employees alike, with covered areas, seating, and a spectacular western view of the water and many construction projects in progress in the city.

A nice view and respite from the sun

Expansive view of Puget Sound from the Seattle Justice Center; Photo by LSV

An article in the Puget Sound Business Business Journal from September 26, 2003 states "...the Justice Center, which has a green roof in addition to a glass insulating buffer wall and an oversize storm water detention tank, the city calculated that the extra design and construction costs amounted to $1,728,100, while the estimated benefits over a 25-year life cycle range from $2,556,900 to $3,708,000..."  Peter Steinbrueck, reporting for The Seattle Times on January 13, 2005 says the city's initial investment is paying off -  "A 2003 study, commissioned by Seattle's Office of Sustainability and the Environment, revealed the Justice Center is saving as much as $148,000 each year due to its green roof."  Read more:  Putting a green cap atop the Emerald City and the excellent November/December 2004 article from Environmental Design + Construction magazine, Sustainability With a View, by Charles Cronenweth.

More Public/Municipal Greenroofs

The Capitol Campus in Olympia - The Capitol Campus in Olympia has had greenroofs for many years.  The Achieves building was built in the 70's with a greenroof (green roof approx 6,000 sf). Stuart Simpson, CEM, LEED A.P., Green Building Advisor, Department of General Administration tells me, "This was done partly, I believe, to conceal and protect the building. Only one of the six stories is above ground. The Capitol Campus also has extensive parking garages that have greenscapes over them (green roof approx 4 to 6 acres). This was also built in the 70's. This year they are being refurbished. There were some leaks. The cover is being redesigned to add more grasscapes."  The capitol campus is considered to be one of the most beautiful in the U.S. and is currently undergoing a $100 million Legislative Building Renovation.

Point Defiance Zoo, Tacoma, WA

The extensive Zoo greenroof right after planting in 2002,
west view. Photo courtesy Boxwood.

Point Defiance Zoo and Aquarium Hospital - Located in Tacoma, the 10,000 sf un-irrigated extensive project was completed in 2002 using a variation of the Roofscapes, Inc. Roofmeadow© Type II Aromatic Garden assembly of mostly sedum varieties established from plugs and chives.  An erosion blanket was used to hold plugs in place.

This earth-friendly, state-of-the-art animal care facility opened on Nov. 1, 2003.  The hospital features many energy-efficient features, including the "living" roof planted with grasses, recycled building materials, solar water heating, and stormwater collection and retention.

The Roofscapes website states, "A key challenge with this project was the load constraint; the maximum load could not exceed 15 pounds per square foot."  Click here for the Roofscapes Project Profile.  The architects were Boxwood, and associate Karen A. Davis Smith tells us the Point Defiance Zoo and Aquarium' s Animal Health Care Facility was designed to provide a variety of color and texture.  It holds approximately 3 inches of growing media with tumbled recycled blue glass cullet perimeter edging.  I asked her who was responsible for promoting the greenroof, and Karen responded "I suggested the idea and William Clark of Sarnafil and I were the primary promoters of this roof.  Kristen Fritsch of Boxwood and Dr. Brian Joseph of the Zoo were fellow promoters as well."  The green roof system is installed over a Sarnafil membrane and includes an electrical leak detection system.  The installers included Teufel Nurseries, Roofscapes and Snyder Roofing.

Point Defiance Zoo Greenroofs by Roofscapes, Inc. Point Defiance Zoo and Aquarium Animal Health Care Facility, Boxwood Architects

Left: Placing the cover. Photo (c) 2004, Roofscapes, Inc. used by permission; all rights reserved. Right: East view of the facility.  Photo courtesy Boxwood.

Seven Northwest EcoBuilding Guild Residential Greenroofs

We now pick up my visit with seven more greenroofs within a few hours.  Hectic, but worth the journey, as Patrick showed me such a wide variety of greenroof applications available to the average homeowner, all at very affordable costs.  These are the rest of the projects we visited on July 19, 2004:

Photo by LSV

Quite a variety of flowering plants with visiting bees. Photo by LSV.

Jon Alexander's Garage - This beautiful Seattle garage was the Northwest EcoBuilding Guild's first project, built in the fall of 2003, and Jon is still an active member today.

This roof was structurally retrofitted to accommodate the green roof, and so we easily climbed up and walked around to see the different plants and insects.  The membrane is a Garland 3-ply with a home made growth medium.  Teuffel products helped with the medium placement.

A couple of GreenTech 4' square modules were added to the roof, and because of the deeper grow media depths of 8.5", Jon Alexander and family are now able to grow vegetables on this portion of his roof such as tomatoes and herbs including basil and oregano.


Tomatoes in July heat Beautiful Yellow and Pink Sedums, mosses and other Greenroof Plants

Left: Tomatoes in GreenTech modules;  Right:  Flowering view of the Alexander garage skylight.  Photos by LSV.


Studio Greenroof
Tom Balderston's Home Studio Office with Ecoroof.  Photo by Patrick Carey, June 14, 2004.

Tom Balderston's Studio Office - This home studio office in Seattle, WA is seen here from a side access street.  This roof was another structural retrofit, completed in the fall of 2003.

Plans include the addition of a passive solar panel, visible from the bottom photo.

 6.5:12 sloped roofs posed some challenges for the Northwest EcoBuilding Guild design team, and were solved by using circular drainage units from Invisible Structures, Slope-Tame 2, plus an erosion-resistant growth medium mix using high fungal content.

Recent rains have proven that the project is not only watertight, but erosion free, as well, with no resulting slippage of growth media or sedum plant plugs.  A soil topping was used - Quick Grass from Excelsior.


Greenroof with passive solar panel

Top:  Sloped roofs posed some challenges for the design team, and were solved by using circular drainage units from Grass-Cel, Photo by Patrick Carey, June 14, 2004.  Bottom:  Section of greenroof building materials.  Photos by LSV, July 16, 2004.

Jeff Mazurek's Art Studio

Sloped and flat extensive greenroofs in the backyard

Art, nature, and play spaces in this greenroofed Art Studio in Seattle.
Photo by LSV, July 16, 2004

The Mazurek's needed an addition to house their two young children's art supplies and encourage artistic expression.  The answer is the two-story loft art studio situated in their Seattle backyard among the beautiful flower and vegetable garden also inhabited by various squirrels, dogs and cats, completed in the spring of 2004..

Overhead shot of the Mazurek Art Studio, Seattle, WA

Overhead view by Patrick Carey

The two greenroof areas actually consist of one highly sloped roof on top, and a shed style pitched roof with a flat section.  The flat portion has a GreenGrid greenroof system, and the sloped areas using a TPO laminated metal grid field welded to the membrane and then filled with Slope Tame 2.  Again, at a 7:12 pitch there was no erosion and the plants at the top of the slope are getting enough water.  The roof areas have large gravel perimeter areas for Jeff to walk on for maintenance.

Mazurek Art Studio Greenroofs

Patrick Carey, Left, and Jeff Mazurek, Right, Striking a Pose; Photo by LSV

Phinney School "Tuff" Shed - Completed last month, the current state of the small Phinney School "Tuff" Shed in Seattle, below, looks more like a brown or rubble roof than a greenroof, but that's because the donated plant plugs are still awaiting planting day.  So, until that time, only the engineered soil mix can be seen.  This project utilizes one of six NW EcoBuilding Guild drainage strategies and detailing developed for residential applications.

Eco-Shed in Seatlle, WA

Phinney School Ecoroof waiting for the green stuff.  Photo by LSV.


Sensitive site design in Seattle

The view of the Linden Orchard Cob Shed from the street

Linden Orchard Cob Shed - As part of his hands-on policy for all Guild members, Patrick chose to design this community greenroof.  "I have to finish my own green roof practicum project where each member of our crew has to do a presentation in public, do a green roof practicum - where you install a small scale green roof on your own - take a written exam on green roof design and installation theory and practice, and train an apprentice under you." Patrick explains.  "Then you get to be a full fledged crew member.  Even the boss has to do it. So now I get to be made fun of by the crew."  Actually, Patrick says he finally had to admit his shortcomings as a carpenter and get
some expert help from a ship builder.

he cob structure is a community effort by a number of volunteers eager to showcase a multitude of sustainable site and building design elements, including the integration of native plants, community gardens, a naturalized rainwater stream swale, organic cob construction, and a greenroof.  Right now the construction crew is working on the roof, and the plants are not yet in.  The small community park project is expected to be finished in a few months.


Cob Shed under construction

Expect to get your hands muddy but have fun if you volunteer at the Linden Orchard Cob Shed project.  Photo by LSV.


View from the Top of Dave Logan's Garage

Notice the potted "chimney" of an Opuntia cactus.  Photo by LSV.

Dave Logan's Garage - Dave's pitched Seattle garage was also one of the first Northwest EcoBuilding Guild greenroofs, finished in 2002, and has served as testing grounds for different plants.

The garage started with a liquid PVC membrane and then used an exo-skeletan for geotextile attachment so there could be mechanical fastenings with no membrane penetrations.  They finally came up with a plant combination that would work under the Cedar tree droppings.

Here I climbed up a side ladder to obtain a view from the top.  Different growth media mixes and plant species have been used here, as part of this extensive greenroof is in the shade most of the day.


Dave Logan's Ecoroof Garage in Seattle

Side view of the picturesque Logan garage ecoroof with the huge Cedar overhanging the back side.  Photo by LSV.

Judy Sohl's Chicken Coop - A lover of all things natural, Judy grows vegetables, native and naturalized flowering plants scattered around her Seattle yard, along with the children's play set and the chicken coop with the greenroof.  The greenroof is very popular with the chickens as it keeps them cool in the summer and warmer in the winter months.

Perennials and Sedums on the Roof in Seattle

The Chicken Coop is a popular place for both chickens and plants.  Photo by LSV.

The growth media is deep enough at 4" to accommodate flowering perennials such as Black-eyed Susan, and a variety of -  what else - Hens and Chicks (Sempervivums).  Rocks placed along the edges act as decorative naturalized borders and also help to reduce wind sheer.   They also serve to keep the sloped growth medium away from the drain and scupper.

A sunny Seattle chicken coop in mid July

A little too much sun in this photo, but you can appreciate the elegant line
of the chicken coop structure.  Photo by LSV.

The Northwest EcoBuilding Guild’s Central Puget Sound Chapter is proud of the efforts and successes of the Green Roof Project.  Future Northwest EcoBuilding Guild projects include four 100 sf kiosks and one larger one at 1,000 sf, which will de designed to mimic the shaded forest floor and will use pumice in the growth media.  See earlier photos and read Patrick's June 2003 Guest Feature article here for additional background and contact info.

More Washington State Residential Greenroof Projects

Greenroof Kiosk


The Northwest EcoBuilding Guild - I will present the following photos representing 11 residential greenroof applications more as a photo gallery than a narrative of specifics.

At left is an information kiosk.


JohnAlexander's Garage Rose Leigh
McLaughlin McLaughlin
Hawkins 45 degree slope!
Slope and a GreenTech Module Sproull Taproot


June 16, 2004: Newly seeded and planted lower garage roof; Photo (c) 2004, Roofscapes, Inc. used by permission; all rights reserved.

Private Residence in Medina, WA - The first phase of the extensive green roof was completed in the summer, 2004, designed by Charlie Miller, P.E., of Roofscapes, Inc., and installed by Teufel Landscaping. This  residence in Medina, WA is receiving a Roofmeadow ® Type III: Savannah two-layer system green roof.  Click here for the Roofscapes Project Profile.

Approximately 2,000 sf at the garage and approximately 4,000 sf at the residence will be green roofed.  The system consists of (from the bottom up) a 2” granular drainage layer, 4” of lightweight growth medium, grasses, sedges, carex, and hand-broadcast seed, peat moss, and jute net over the top. The seeds have been obtained from Germany to Oregon. There is a 3’ strip of blue oat grass and beach strawberry plugs at the exterior margins.

Roofscapes, Inc. Greenroof Private Residence, Medina, WA

Early construction Medina residence photos; Photos (c) 2004, Roofscapes, Inc. used by permission; all rights reserved.

Crushed granite is being used at the exterior margins, and crushed marble is being used in the interior margins of the roof garden.  A temporary irrigation system is being used 5 - 6 times a day for about two minutes each time to keep the seed bed moist throughout the germination process.

Growth media arriving overhead Temporary irrigation for seed and plug establishment

Left:  Placing the growth media; Right: Temporary irrigation at borders.
Photos (c) 2004, Roofscapes, Inc. used by permission; all rights reserved.

The roof is designed to not need irrigation or fertilizer once established.  "We will maintain the roof plantings for two years on this project, but the maintenance is quite minimal (bi-weekly check ups, with almost no ‘work’ associated with it)," says Tatia North of Teufel Landscaping.

Plants poking up through the jute blanket

Medina Private Residence:  The grass seed is just starting to germinate. Strawberries and blue oat grass at border. Photo (c) 2004, Roofscapes, Inc. used by permission; all rights reserved.


View of greenspace and apartments

Intensive greenroof atop the parking garage, Redmond, WA.  Photo of 12.9.03 courtesy Dave Frentress.

Apartment Complex in Redmond, WA - Glacier Northwest is a company based in Portland, OR and offers the "Everdure Caltite" system for waterproof concrete, which is being applied to greenroofs in Seattle and Portland.

According to company literature, "Everdure Caltite allows a simple structural waterproof concrete deck to serve as the green roof, eliminating the need for membranes.  The elimination of membranes simplifies the design, construction, and maintenance of new green roof projects."



Construction in Redmond, WA Cars enter and exit parking under deck

Left:  Construction, early 2003;  Right:  7.31.03 - Underground parking offers greenspace on top.
Photos courtesy Dave Frentress.

Dave Frentress of Glacier Northwest, Inc. says, "We have a large greenroof using our waterproof concrete - with no membrane at all - at an apartment complex (Jefferson at Marymount) in Redmond, WA.  All the cars park underneath the green roof, and the green space has road access around it for fire regulations.  By not using a membrane and eliminating the topping slab, the owner (JPI) saved over $100K.  It is just a simple post tensioned concrete deck, supported by columns in the parking area below."  The apartment complex with intensive greenroof was completed in 2003.

Intensive greenroof over waterproof concrete parking deck

Intensive greenroof over Caltite deck offers recreational greenspace for residents of the apartment complex.  Photo of 12.9.03 courtesy Dave Frentress.

Educational Greenroofs

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2004 ASLA Design Award of Merit winner
Cedar River Watershed Education Center. Photo by Nancy Rottle; Source:

Cedar River Watershed Education Center - Located in Seattle, WA, Jones & Jones Architects and Landscape Architects designed the Center in 2001.  The Seattle Public Utilities website offers an Implement Design and Construction Case Study PDF of this beautiful natural center which states "The Cedar River Watershed is the primary source of water for Seattle and more than two-thirds of King County.

The area receives well over 60 inches of precipitation a year. Wherever possible, falling rain is displayed, and its natural flow path demonstrated. The metal and earthen roofs are models of both paved and pervious surfaces’ effects on water flow, with water gushing from the metal surfaces, in contrast to the absorptive and slow-release function of the planted earth covering.

Living roofs juxtaposed to metal roofs demonstrate the natural filtering capacity of soil and the role of plants in water retention to delay runoff.  Rainwater is captured to demonstrate reuse, and is displayed in artful basins and employed to play 'rain drums.'”



Click to enlarge photo Click to enlarge photo

Natural landscaping at ground and roof levels.
Photo Left: Nancy Rottle; Right: Lara Swimmer

Nancy Rottle, RLA, ASLA, is currently an assistant professor in the Department of Landscape Architecture at the University of Washington, and worked as a landscape architect for Jones & Jones Architects and Landscape Architects for over a decade, where she served as project manager for the Cedar River Watershed Education Center through the design phases and was lead landscape architect through construction.  She is currently conducting a post-occupancy evaluation of the facility, and writes "The design mission was to create a place where buildings and landscape are integrated as a full-scale exhibit to convey a sense of the cultural and natural history of the Cedar River Watershed and the resource and ecological management values embraced by the City."

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Left: Orientation Kiosk. Photo by Jones and Jones: Right: Forest and meadow flow onto the roof.
Photo by Nancy Rottle.  Source:

Nancy Rottle credits her former associates at Jones & Jones for being visionary.  She says, "We began the planning and design for the Cedar River Watershed Education Center roof very early in the green roof movement - originally proposed in the 1993 Master Plan, and then modified (greatly reduced in scale, and with a new building complex design) in the Schematic Design in 1994.  Jones & Jones was the originator for the idea, having used them previously in zoo design, and proposed them for other (unbuilt) nature education centers."

Jones & Jones specified Sarnafil as the roofing system; they oversaw construction by the general contractor (Berschauer Phillips) and the landscape subcontractor (SH Landscapes).  Nancy reflects, "The roof section is deep - almost 12 inches - since we wanted to grow ferns and other native plants that required deeper soil.  In retrospect, I think we could have made the soil shallower - but we know so much more now!"

Planting the greenroof

Bonnie on the Center's roof, 2001.  Photo courtesy Nancy Rottle

Nancy continues, "The Watershed Education Center supports 1500 sf of an intensive green roof that is planted with ferns and native plants endemic to local rock outcrops in the adjacent watershed.  Covering three buildings and an interconnecting walkway, these pitched living roofs model the spongy, water-retentive qualities of a healthy watershed, contrasted to the flashing outflows of the metal roofs and other impervious surfaces. Intended to merge the building complex with the surrounding forest environment, the green roofs also inspired an indoor art installation of giant suspended root wads that pulse with waterlike energy of blue argon light.  The green roof is part of a set of features that express the water cycle and display the natural and human infrastructure that is necessary to ensure healthy water resources."

Read the complete 2004 ASLA Design Award of Merit Case Study Press Release with additional photos here.

The Evergreen State College Extensive Greenroofs

The recently completed Evergreen State College Seminar II Building. Photo Courtesy Tom Regney of the Garland Company.

The Evergreen State College -  The Evergreen State College Seminar II Building in Olympia, WA was recently completed this winter 2004, and it is slated for a Gold level LEED certification.

Michel George, the former Facilities Services Director at The Evergreen State College, was involved with the idea of the greenroofed areas, which cover 40% of the roof surface.

Thomas J. Regney promoted the Garland Company's GreenShield roof system to project architect Mark Cork at Mahlum Architects and says,  "We worked together for nearly two years on the design of the roofs and once it was finally awarded to Wayne's Roofing as the roofing contractor, and Northwest Landscape as soil, drainage layer, and plant installer, we had a team."


Designed by Mahlum Architects

Evergreen State College Model by Mahlum Architects: Source:

Tom adds, "It was a great experience be involved with the evolution of these buildings and roofs.  Garland is very committed to all of our roof projects and we are on site during installation to ensure specification compliance.  For over a year during the Evergreen State College project I was on site approximately three days a week to inspect the work in progress.

This was a huge commitment to the project, but paid off in beautiful green roofs and a waterproofing system that passed all flood tests and infrared analysis 100%.  This was quite the accomplishment considering there are many roof areas that total around 50,000 sq. ft.  Furthermore, many of the roof areas received heavy foot traffic and were used as work surfaces for the other trades, and still maintained their integrity."


The Evergreen State College The Evergreen State College

Photos 2004, Courtesy Tom Regney of the Garland Company.


One year old extensive greenroof

Washington State School for the Blind Ogden Resource Center:  Courtesy of and Photo Credit  to Stuart Simpson, Dept. of General Administration, Vancouver, WA

Washington State School for the Blind Ogden Resource Center - The School for the Blind in Vancouver, WA, installed the newer technology of a portable greenroof system in 2003, and the project was dedicated last summer. GreenGrid™ was chosen and says "The intent was to integrate as many sustainable elements into the new building as possible.

The 6,640 sf GreenGrid™ Modular green roof will help to manage stormwater, decrease heat loss and heat gain, and reduce HVAC energy requirements that uses non-berry strawberry plants." 

The modules were pre-filled by with the specified GreenGrid™ lightweight soil media and preplanted with drought-tolerant native coastal strawberries (Fragaria chiloensis).  The green roof was completely installed in approximately 30 hours.  Terra Architects were the designers,  and GreenGrid says "The architect selected the plant materials for the GreenGrid™ based on the drought tolerance and attractiveness of the coastal strawberries ... Terra Architecture plans to monitor energy expenditures at ORC over the next three years in order to assess the impact of the sustainable design features to be able to recommend them to the State of Washington and to future clients based on actual data."   Read the GreenGrid™ Project Profile here. 

The Superintendent of the School for the Blind, Dean Stenehjem, is credited with promoting the greenroof and other elements of sustainable design. "The proximity of the School for the Blind in Vancouver to Portland, OR may have had something to do with the incorporation of the greenroof into that project," says Stuart Simpson, Department of General Administration. "The Vancouver area has serious concerns with storm water, so that also played into the decision for a green roof.  Also the building is naturally cooled, and the green roof helps there, as well."

Facade of the School for the Blind, Vancouver, WA Installing the GreenGrid Modules

The School for the Blind greenroof. Left: Courtesy of and Photo Credits to Stuart Simpson, Dept. of General Administration, Vancouver, WA; Right: GreenGrid

Local Systems, Architects, Landscape Architects and Designers

Boxwood  - Boxwood is dedicated to holistic design, design driven architecture, and sustainability.  Karen Davis Smith says, "We view design as a process of discovery originating from dynamic interplay between clients and designers, merging needs and desires with poetic thinking to arrive at innovative solutions.  Conservation and preservation of natural resources is considered by Boxwood as an integral responsibility of designers and of paramount importance in our design approach.  Our work is intentionally diverse,  and includes wineries, transit facilities, medical facilities, community centers, recreational facilities, cultural and interpretive centers, and graphic projects such as web site design, comprehensive identity packages, environmental graphics and specialty promotional pieces."  Aside from the recently built Point Defiance Zoo and Aquarium's Animal Health Care Facility in Tacoma, WA - see above -  Boxwood also designed the Carlton Winemaker's Studio in Oregon.

The Lewis Creek Visitor's Center - The Lewis Creek Visitor's Center in Bellevue, Washington, is currently under construction, and will also have a Roofscapes extensive type green roof system with sedum type plantings.  Cherry Lietz Snelling of Boxwood and Jenz Swenson of Parametrix were the primary promoters of the green roof for this project.  It is expected to be installed by Teufel Nurseries and Roofscapes as well. 

The Garland Company - Tom Regney states, "The Garland Company has always been on the cutting edge of technology in the roofing and waterproofing industry.  This has kept us on top as far as the quality and creativity in this market place.  We have the strongest roof systems on the market and the most knowledgeable sales force in the country to market our systems.  We have always attempted to be 'environmentally friendly' in our thought process.  This mind set guided us to spending a good deal of our research dollars in Germany to find out more about Green Roofs.  We have spent more time and money on green roof research than any other company that I am aware of in the United States. Garland has always believed that you have to become an expert on a subject before you can market it.  We have done this with Green roof technology resulting in a knowledge level unsurpassed in the industry. This research, and lab time has allowed us to have a soil mix that is very light weight when fully saturated and a membrane system that has the best puncture resistance in the market."

Tom says he is working on five different upcoming projects that are all residential based, and two other larger commercial/institutional projects are seriously considering green roofs.

Mithun architects + designers + planners - Debra Guenther, a Landscape Architect at Mithun says the firm is founded on a culture of continuous learning. The firm’s collaborative disciplines include architecture, urban planning, interior design and landscape architecture, as well as national leadership in resource sensitive and sustainable design.  Each project brings this diverse team of disciplines together in a cooperative environment to create innovative solutions for clients.  The firm is best known for its design of the Salish Lodge; IslandWood, the innovative environmental learning center on Bainbridge Island, Washington; and the REI Stores, including the 2000 multi-award winning 43,000 sf green roof over the parking area of the Denver, CO Flagship REI Store.  Other greenroofs outside of WA include Lloyd Crossing, a cutting-edge sustainable urban design plan for 35 blocks in Portland, Oregon’s city center; and Jackson, Wyoming’s Teton Science School (Spring 2005).   Mithun greenroof projects in progress include:

South Lake Union Sustainable Resource Guide - Mithun has been promoting greenroofs as a solution to stormwater management, habitat connections and reducing the urban heat island for about the past ten years. Greenroofs are a key component in Mithun’s recommendations for the redevelopment of urban neighborhoods in Seattle’s South Lake Union and Portland’s Lloyd Crossing. Clients have been interested in the environmental, community and tenant benefits as well as the branding opportunities. These neighborhoods are targeting residents and businesses that are part of what author Richard Florida calls the “creative class” – people who identify with innovation and choose to locate in places that reflect their values.

Woodland Park Zoo: Family Science Learning Center - The Zoo's new Family Science Learning Center building is scheduled to open in 2005 and will provide families with an indoor place to learn about animals and their habitats.  The project may include a 7,000 sf green roof.  Should funding be acquired, the roof system will be American Hydrotech installed over plywood, including the “egg carton” layer to assist in holding soils on the shallow curve of the roof.  The design concept is to raise up a piece of the forest floor - the surrounding Pacific Northwest lowland temperate forest, including kinnickinnick, sword fern, salal, and nodding onion.

Brightwater - The design and planning for King County’s new wastewater treatment facility in Woodinville, Washington is currently underway and scheduled to open in 2010. The client and design team are considering the possibility of including green roofs on parts of the facility which could range from an 1/8 of an acre to 1.5 acres of green roof. Their evaluation strategy includes roof structure (many functions require the use of concrete roofs which would support green roofs with minimal change to the structural cost); views from the neighbors and highways; education (plant tours are regularly scheduled); LEED points; and employee retention and productivity from the improved environment.

Read the recent Earth Share of Washington's Green Companies In Focus Interview with Bert Gregory, President & CEO of Mithun here.

Olson Sundberg Kundig Allen - Stephen Yamada-Heidner is one of a couple of LEED certified architects in the Olson Sundberg Kundig Allen office and believes that OSKA has more recent residential greenroof projects going than most Northwest firms.  "We recently completed a house with a Hydrotech system in Mercer Island, a Sarnafil based system with Allworth Nussbaum in Hunts Point, and currently have another Sarnafil system under construction with Charles Anderson in Medina.  These are all high-end residences."

Profiles, photos and descriptions of these projects can be found on the Olson Sundberg Kundig Allen website under Projects: "An American Place" and "Bird Watcher's House."  Projects in progress include "Maury Island Residence," "Art House," and "Rainier Club Expansion."

Difficulties with Local Government or Area Residents?

"Education was necessary to overcome many misconceptions about green roofs.  Some of these are that they inherently leak, that they are untested systems, and that they will not last long compared to other types of roofs.  Since every situation has its own unique set of circumstances, creativity is really the best approach.  Education can often open up possibilities, and getting people together to work towards a common goal can be beneficial for all involved," shares Karen of Boxwood.

Nancy Rottle, formerly of Jones & Jones, says there were initial concerns on her project. "At the Cedar River Watershed Education Center there was concern from the maintenance division of the client (City of Seattle) that the roofs would leak.  At the time there wasn't enough data or precedents to convince them otherwise.  The green roofs were therefore limited to the covered walkway, the restroom and custodial buildings, and kiosks.  The idea has gained much more currency within the City of Seattle. I expect it's like any other new idea - t takes time to become popularized."

"The incentives that currently exist in Seattle’s Flow Control Manual are not enough to encourage developers to take on the additional up front costs," says MITHUN.  "For many projects, the capital costs are not born by the same entity as the operational costs, so the life cycle value doesn’t influence the decision. Public agencies and institutions who are building owners and occupants have been the leaders to date."

Tom Regney of the Garland Company adds, "Washington State needs to enhance the incentive for green roofs. Their higher up front cost can be a difficult obstacle to hurdle."

A perfect example of higher upfront costs, insufficient public education and perhaps a certain amount of misinformation can be gleaned from the recent decision regarding the proposed greenroofs atop Bellevue City Hall.  Up to five greenroofs had been debated, and although benefits, design and costs had been discussed and proposed for months by SRG Partnership Architects, the greenroofs were finally scrapped.  Apparently the Bellevue City Council wasn't convinced.  They worried over the high construction costs and perceived higher maintenance costs, and one said he had spoken with a roofing consultant who had questioned possible water penetration of the building envelope, and even aesthetic values - see the City of Bellevue City Council Minutes of April 12, 2004, pages 5 and 6.  The Seattle Times reported on May 26 that "The only major casualty of the budget crunching was a proposal for an environmentally friendly "green" roof.  It was quietly dropped from a final list of alternatives.  Council members had shown little interest in the idea of putting plants and grass on top of roofs, an idea architects proposed as a way to absorb water and heat."

Overcoming Barriers and Looking Towards the Future

"The green roof needs to satisfy the project goals. When these are in sync with each other the budget shifts to allow for the investment. The goals we have seen that drive the desire for a green roof have typically been to express the mission of the organization or encourage branding of a neighborhood as a sustainable place. To accelerate the mainstream use of green roofs both public and private actions are important. Policies such as the Endangered Species Act and the Clean Water Act are at the root of the Pacific North West’s leadership in water quality design responses. Expanding public policies, as seen in Germany, can have a big impact on the use of green roofs in broader sectors of the community," states Mithun architects + designers + planners.

"Market demand in the private sector is the key driver. Green roofs will proliferate as consumers and tenants begin to ask for space and locations that includes green roofs because of the employee productivity and retention benefits for employers, the perception of being in a green building, and the sustainable neighborhood identity. The learning curve for contractors will also lessen and decrease the cost for green roofs, making it within reach of more projects."

Stuart Simpson, Dept. of General Administration is the Green Building Advisor and advocate for the State is trying to look ahead.  "I work with state projects and K-12 school projects, but typically not Universities.  We are a State Agency responsible for project management services related to design and construction of state buildings, including community colleges."  Stu adds, "I have not been involved directly with a Green Roof project, however, I have been trying to promote them in state projects where appropriate."

Quoted in the June 2004 issue of Sustainable Industries Journal, City of Seattle sustainable building coordinator Lucia Athens explains why Seattle has no plans to institute economic incentives for ecoroofs. “Green roofs are pretty new and we don’t know how much they perform.  The city would have to have a real clear understanding of how they work before we would offer incentives.”

But Mithun also comments that Seattle's Department of Planning and Development's "Lynne Barker is working on the City policy and incentives that will encourage green roofs. They have looked at incentive programs such as Arlington, Virginia that trades FAR for green roofs, however with on-going discussions with the development community, they are currently looking at some combination of stormwater and open space credits to spur the use of green roofs."

Raingardens and Greenroofs Manage Stormwater Naturally

Cedar River Watershed Education Center Greenroof and Raingarden.
The roof's scuppers drain into the raingarden.  Photo courtesy
Nancy Rottle.

Nancy Rottle shares her personal opinion on the future for the further widespread application for greenroof projects in WA.  "With Chinook salmon listed as a "Threatened" species, there has been greater attention to stormwater impacts on streams and to some extent, rivers.  The stormwater benefits I believe will be the greatest selling
point, whether in rural areas (where the highest quality streams are so easily degraded) and in urban areas, where the impacts are so obvious.  As global climate change comes the fore of peoples' perceptions, the "heat-island" rationale may also encourage more conversion to and construction of green roofs - even in Seattle!  The last few summers
have been very hot - following the global pattern - and the city's higher temperatures are undoubtedly affecting biodiversity, including higher water temperatures in salmon-bearing streams (salmon and another listed species, Bull Trout, for example, need cold water).

Nancy also adds "Publicizing precedents is invaluable."  She feels that "Working with jurisdictions to implement codes that allow green roofs and offer incentives to developers" will further the cause, as well as "Funding for research to prove and publicize their benefits, and to help overcome any liabilities."

"I get more calls on this technology than anything else in the industry," says Garland's Tom Regney.  "With the amount of interest, I can only see many green roofs going down in the greater Seattle area."

"As understanding increases, widespread application could occur here," concurs Karen Davis Smith.  "This area includes a huge population of individuals and organizations that want to build sustainably.  There are local groups promoting green roofs with the goal of widespread residential application.  Widespread application for industrial buildings would make a great deal of difference in terms of maximizing the benefits of green roofs, but this can be challenging to inspire without incentives or requirements in place," emphasizes Karen. " I believe that as more examples are being constructed, this creates a lot more interest and also comfort level with the roofs."

On May 8 of this year the Northwest EcoBuilding Guild created more interest by holding its first Green Roof Tour, Presentation and Workshop.  Eight greenroofs were visited within the Seattle City limits - two of which could be walked on, and one with a 6.5 : 12 pitch.  They expected 15 or 20 people and over 130 showed up!

Research, Design + Build = A Prosperous Outlook

Patrick reiterates that after the Guild completes a total of 20 residential green roofs by the end of this year, the Green Roof Project will then focus its energies on public education and research.  This year it will begin to monitor eight green roofs and 12 test panels, and  monitoring activity will focus on stormwater runoff, water chemistry, and various growth media experiments.

In addition, the Northwest EcoBuilding Guild hopes to collect as many descriptions of residential green roof projects as possible and and include them on its web site and to share their methods of construction and design as well as invite and offer critiques. This year the Guild started the "Residential Green Roof Plant Society" which is basically a Yahoo News Group composed of owners of residential green roofs who compare their successes and failures with various forms of plants and growth media.  But you have to live under one to qualify for membership.  If you are an " expert" without a green roof, sorry, you have to walk the walk first.

Based on its experiences in directing the Guild project, hadj design is currently exploring a design-build business model for green roof design and installation that includes both affordable housing, higher end housing, and commercial.  "The biggest challenge with the biggest ecological pay off is the residential market, Patrick insists.  "There is over eight  times more residential roof surface than commercial.  As you move into the suburbs, this ratio gets even larger.  Also square foot per square foot, residential green roofs have more ecological impact than commercial.  This year we hope to prove ourselves as a viable design-build business with our current host of clients.  Next year we tackle the housing developers."

Seattle is a leader in so many ways, and with continuing public support, projects from numerous sectors and local leaders like Patrick Carey championing residential greenroofs and working to create affordable systems, perhaps economic incentives and other opportunities are not that far off after all.

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Linda is founder and publisher of, a greenroof design consultant, and has been a Delta Air Lines international flight attendant since 1979.  She went back to school and received her Bachelor’s of Landscape Architecture degree from the University of Georgia in 2000.   She welcomes your comments; contact her:

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