Green Building News

Green Building News January 2008

January 7, 2008

Green roofs are hard-working landscapes on the Portland skyline

by Aimee Brown

Reprinted with permission from Oregon State University's "Oregon's Ag Progress" magazine, Fall 2007.

Portlandia greets visitors to the Portland Building with a giant outstretched hand. The symbol of Portland, Oregon, the copper sculpture (second only to the Statue of Liberty in size) is what most people notice about the downtown headquarters of the city's government. But inside the building, at the top of 17 flights of stairs, the Portland Building opens onto a rooftop meadow of living plants and one of Oregon State University's latest agricultural experiments.

In this urban environment colored in hues of steel gray and asphalt black, the rooftop offers a patch of rich color and texture, a living quilt of gold, red and green plants, some in bloom and buzzing with insects. It is not a roof-top garden with potted palms and banana plants as I had imagined, but it is definitely a growing, thriving rooftop meadow in the middle of a major metropolis.

The living, breathing roof atop the Portland Building is a hard-working landscape 17 stories above the city’s streets. Where some people see air vents and pigeon roosts, OSU horticulturists see a new frontier for creating landscapes that help absorb storm water, reduce city heat and soften the hard edge of the concrete jungle. Photo: Lynn Ketchum

Looking across the city from this vantage point, I see an environment filled with impermeable surfaces—roads, buildings and parking lots—that separate the falling rain from the spongy ground. Western Oregon's heavy winter rains can't penetrate these hard surfaces. As a result, storm water runs off roads and sidewalks, overflowing treatment facilities and sweeping pollution into rivers and on downstream. Portland is investing $1.4 billion in its Big Pipe project to keep most of the city's sewage and storm water from overflowing into the Willamette River. The green roof I'm standing on will help reduce run-off and bring some green back into the urban landscape.

"Storm water management is a primary reason that many city governments are interested in green roofs," said Erin Shroll, the lead researcher on OSU's Green Roof Technology project. "But there is a host of other benefits associated with the roofs, ranging from better building insulation to reductions in the urban heat island and increases in wildlife habitat."

Researchers Erin Shroll (front) and David Sandrock are monitoring an array of experimental green roofs at OSU’s new Center for Urban Horticulture. Photo: Lynn Ketchum

There are 12,500 acres of rooftop in the city of Portland, according to Tom Liptan, an environmental specialist with the city's Bureau of Environmental Services, who has pioneered green roofs in Portland. He estimates that just a few, about 25 acres, are planted as green roofs, either as old-fashioned roof gardens or as what he calls eco-roofs, specially designed with a lightweight growing medium, an assortment of rock-garden plants and other vegetation and an underlying waterproof membrane.

As part of Portland's efforts to promote sustainable development, city leaders are encouraging the use of green roofs as a lightweight, low maintenance, vegetated alternative to conventional rooftop materials on both residential and commercial buildings. There are now more than 80 green roofs within the city, and more are being planned. But up until now, little has been done to determine what plants are best suited for roof-top use in the wet-winter, dry-summer climate of Portland.

Green roofs aren’t always green. The bright assortment of sedums and other rock-garden plants attract pollinating insects to the top of the city. Photo: Lynn Ketchum

Planting green roofs is more than blanketing a roof with sedums and succulents and hoping for the best, according to David Sandrock, a researcher in OSU's Department of Horticulture. "The science behind creating a successful green roof is still in its infancy," he said. "This is a brand new landscape where nothing is truly native. There's a lot to learn and a lot to explore."

To help explore this new frontier, OSU joined into a partnership with Liptan and the city of Portland to study the green roof on top of the Portland Building in the heart of the city's downtown area.

"Each part of the city, and to a degree each part of each roof, has its own microclimate and a variety of conditions that must be considered before planting," said Shroll. She and Sandrock are examining what plants will be most successful on rooftops across the Northwest.

To learn more about rooftop microclimates and the plants that could thrive in each, Shroll and Sandrock are leading a green roof research program at the newly developed Oak Creek Center for Urban Horticulture on the southwest side of the OSU campus in Corvallis. There they built 24 raised test plots, each planted with a mixture of six different plants native to the Willamette Valley and two non-native plant varieties. The plots represent extensive roofs, that is, green roofs with two to six inches of growing medium and not intended for foot traffic. These green-carpeted roofs are in contrast to intensive rooftop gardens, what people generally imagine when they first hear about roof-top plantings, with patios and gardens that can be used as outdoor living spaces.

Researchers monitor the growth of each kind of plant. Photo: Lynn Ketchum

Extensive roofs are usually within the normal load-bearing capacity for commercial buildings and do not require additional structural reinforcement before installation. However, said Shroll, approval from a structural engineer should be the first step in designing any green roof. In contrast, intensive roofs tend to have deeper soils to support a wider variety of plants and may require structural modifications to be considered safe.

"But as far as storm water management, extensive green roofs are the workhorses," said Sandrock, who leads OSU's program in landscape design. "In our test plots, it's all about reducing run-off and the overflow of winter rains. Keeping the plants alive through the dry summer is part of the cycle."

The idea of watering extensive roofs is new to the green roof industry, and it is generally unnecessary in places where summer rain is abundant. The researchers fitted their plots with an irrigation system that drips the minimum water necessary to carry the plants through the dry season and ensure they are ready for rapid uptake of moisture when the winter rains begin to fall.

Data loggers arrayed above the plants automatically record air temperature and light every 30 minutes. Additional sensors buried beneath the soil measure how the plants and substrate affect the temperature of the roof below. Photo: Lynn Ketchum

In order to use less water for irrigation, Shroll and Sandrock collect and store rainwater that drips from the conventional roofs at the Urban Horticulture Center during winter. They've also created a bioswale on the property to help absorb and filter run-off from the Center's buildings before it enters nearby Oak Creek.

Back at the Portland Building, Tom Liptan points out honey bees patrolling the rooftop plants. Where are they coming from? How did they find their way here? Where are they going?

"I mentioned them to the mayor, and he suggested that we put a beehive up here," Liptan said.

OSU horticulture student Corey Petersen and colleagues monitor the microclimates across plots of experimental plantings on the Portland Building rooftop. Photo: Lynn Ketchum

Green roofs are opening new territory for cities and homeowners alike. "Putting in a green roof begins to address the 'What can I do?' stumbling block that many people face when thinking about sustainability issues," said Sandrock. "It helps people understand that by doing something relatively small, each individual can have a big impact on the health and sustainability of their communities."


Renewable Electricity Standard Good News for Economy, Energy Consumers and Carbon Dioxide Reduction

A new comprehensive analysis of the Renewable Electricity Standard (RES) in the pending House and Senate energy legislation shows that, if adopted, the RES would cut consumer energy bills and carbon dioxide (CO2) emissions as well as stimulate job growth.

According to ACEEE, which authored the five-month study, the RES would in 2030 reduce CO2 emissions by 100 million metric tons (MMT), save 22 billion kilowatt-hours (kWh) of electricity usage, create 21,000 net new jobs and displace a total of 32 500-megawatt (MW) conventional powerplants. This proposal would save consumers $5 billion in 2030 and a cumulative $60.5 billion through 2030.*

“RES saves money for consumers in all regions, and for the nation as a whole,” said Executive Director Steven Nadel. "Although the opponents of the RES claim that it would raise electricity prices and harm regions like the Southeast, ACEEE’s analysis shows these concerns to be based more on political rhetoric than substantive facts,” continued Nadel. According to the ACEEE report, the direct energy efficiency savings, and the indirect impacts of efficiency and renewable energy on natural gas and coal prices, more than offset the slightly higher cost of renewable energy. These conclusions apply to both a national analysis and to separate analyses of the Southeast and the Midwest regions.

The study further examined these renewable and efficiency policies against a climate policy framework similar to the Lieberman-Warner America’s Climate Security Act under consideration by the Senate Committee on Environment and Public Works. These scenarios showed even greater benefits in terms of lower energy prices, greater consumer savings and a stronger economy from setting RES and resource targets. “Renewable electricity and energy efficiency (RES and EERS) policies should be cornerstones of our climate policy. By enacting the RES in the energy bill, Congress can make the best down payment possible on reducing carbon emissions in the electricity sector,” said Policy Director Bill Prindle.

ACEEE used ICF International's IPM® model to calculate energy, capacity, wholesale electric and natural gas prices, CO2 emissions and other impacts of the RES provision. IPM® is widely used by federal and state agencies as well as utilities for resource and policy decision-making. The economic analysis was performed using ACEEE's DEEPER model, which evaluates such policies for their overall consumer savings, job impacts and economic output.

Other key findings include:

  • A more aggressive set of renewable and efficiency standards, a 15 percent RES coupled with a separate 15 percent EERS, would produce even greater benefits. This "15-15" policy package would by 2030 displace the need for 242 new 500-MW conventional powerplants, reduce annual CO2 emissions by 590 MMT, and save consumers a cumulative $591 billion on energy bills. The "15-15" policy would also create 259,000 net new jobs in 2030.
  • In a climate policy scenario based on provisions akin to the Lieberman-Warner bill, ACEEE applied the IPM® model in similar fashion, finding that the RES provision by 2030 would displace the need for 110 new 500-MW conventional powerplants and reduce annual CO2 emissions by 750 MMT. The RES would reduce average wholesale electricity prices slightly, create 31,000 net new jobs and save nearly $132 billion in cumulative consumer energy bills.** Economic benefits are greater in the climate policy scenario since efficiency and renewable resources reduce the cost of carbon credits in a cap and trade system.
  • The more aggressive "15-15" policy package combined with climate policy would avoid the need for 306 new 500-MW conventional powerplants and 958 MMT of CO2 emissions. This policy package would reduce average wholesale electricity prices by 1.3 cents per kWh, create 329,000 net new jobs in 2030 and save consumers over $800 billion cumulatively on energy bills.

“The 15 percent efficiency plus 15 percent renewables package substantially reduces the costs of a greenhouse gas cap and trade program,” stated Nadel. “Given these benefits, we hope that a package along these lines will be included in a final climate bill.”

The House provision reflects the growth of state RES (in place in 25 states and the District of Columbia) and EERS (similarly set long-term resource targets for utilities in some 12 or more states). The RES provision would build on this experience, moderately expanding this policy approach through a national standard and requiring 15 percent of electricity sales to be provided through renewable sources by 2020. Up to 27 percent of the resource requirement can be met through energy efficiency.

Assessment of the House Renewable Electricity Standard and Expanded Clean Energy Scenarios can be downloaded for free at A link to several graphics illustrating the findings is at

* Part of these benefits stem from the RES allowance for energy efficiency to qualify for up to 27 percent of resource requirements. The analysis also looked at more aggressive renewable (RES) and efficiency (EERS) targets, including a 15 percent renewable and 15 percent energy efficiency standard.
** Estimate of consumer energy bill savings, wholesale electricity prices and job impacts assumes a climate policy reference case. Macro-economic impacts of the climate policy alone were outside the scope of this project.


Green Collar Jobs: The New Cash Crop

ASES’ new report shows renewable energy & energy efficiency industries generating massive job growth, with up to 40 million jobs by 2030.

Do you have a green job? You will… A new report from the nonprofit American Solar Energy Society shows that as many as one out of four workers in the U.S. will be working in the renewable energy or energy efficiency industries by 2030.

This is the nation’s first comprehensive report on the size and growth of the renewable energy and energy efficiency industries – and the numbers are great news for American workers. This green collar job report shows that these industries already generate 8.5 million jobs in the U.S., and with appropriate public policy, could grow to as many as 40 million jobs by 2030.

“The green collar job boom is here,” said Neal Lurie, Director of Marketing of the American Solar Energy Society. “Renewable energy and energy efficiency are economic powerhouses.”

This new report officially released on Thursday, November 8 in Washington D.C. The report is called Renewable Energy and Energy Efficiency: Economic Drivers for the 21st Century. It is available for free download at ASES. Research was led by internationally renowned energy economist Roger Bezdek, Ph.D., President of Management Information Services, Inc, based in Washington, D.C.

Key findings of the report include:

  • By the year 2030, the renewable energy and energy efficiency industries could generate up to $4.5 trillion in revenue in the U.S., but only with the appropriate public policy, including a renewable portfolio standard, renewable energy incentives, public education and R&D.
  • The 40 million jobs that could be created in renewable energy and energy efficiency by 2030 are not just engineering-related, but also include millions of new jobs in manufacturing, construction, accounting and management.
  • Renewable energy and energy efficiency industries today generate nearly $1 trillion in revenue in the U.S. contributing more than $150 billion in tax revenue at the federal, state and local levels.
  • Revenue from the energy efficiency sector -- including from energy efficient windows, appliances, insulation and recycling -- is currently larger than revenue from renewable energy, but the renewable energy industry is growing much more quickly.
  • Solar, wind, ethanol and fuel cells are likely to be some of the hottest areas of growth.

The study will serve as a guide to national, state and local leaders eager to attract renewable energy and energy efficiency businesses and to establish new manufacturing facilities and sales offices.


New Product: Combination P-trap Replacement and Drain Management System

PF WaterWorks, a Houston based consumer products company, has launched a new plumbing product - PermaFLOW™. PermaFLOW™ has been affirmed with the stamp of approval by IAPMO testing and received UPC certification for the US and Canada.

Although a conventional p-trap serves as a necessary component of a drainage system, the simple design has often been prone to problems. The PermaFLOW™ Drain functions like a p-trap in normal use, but also has added technology to ensure the “permanent flow” of water. Unlike traditional p-traps, PermaFLOW™ is made of clear ABS plastic, so potential problems are not only seen, they can be diagnosed and quickly remedied. The inlet and outlet pipes on the p-trap are angled to increase flow turbulence. This helps break and propel debris which minimizes deposition and prevents the sink from becoming clogged. Inside PermaFLOW™ there is a rotating paddle that can clear blockage with a turn of the outside mounted dial. This rotating paddle feature also provides users with a by-pass mode to quickly avoid the blockage until convenient maintenance may be performed, thus eliminating the need for expensive and potentially dangerous or harmful chemicals found in drain cleaners.

Learn Green Building From Experts - Classes Start Jan. 21

You can design and build the solutions to the world's worst ecological problems.

Buildings consume 75 percent of electricity, produce 40 percent of greenhouse gasses, are the primary producers of waste and pollution, and are the source of increasing rates of respiratory diseases due to toxic materials and bad air handling systems.

The good news is that we know how to cut the waste, consumption and health hazards to zero at very low cost and in ways that save enormous amounts of money.

The San Francisco Institute of Architecture has been providing leading-edge education in ecological design since 1991 and offers the most comprehensive professional education in ecological design and green building in the world.

See the WINTER 2008 Class List.

NESEA's BuildingEnergy08 Conference and Trade Show - March 11-13

This year's event takes place at the Seaport World Trade Center in Boston, MA. Visit the NESEA web site for more information.


GLOBE 2008 - March 12-14

The 10th Biennal Trade Fair and Conference on Business and the Environment held in Vancouver, B.C. Biennially, thousands of environmental business leaders, corporate environmental managers, sustainability practitioners, financiers and government officials come together in Vancouver to explore corporate sustainability, business growth, energy solutions, responsible investment and urban development. Visit Globe 2008 for more information.

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