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The Oregon Sustainability Center, still being developed in Portland, is expected to be a superlative accomplishment for American green building. Meanwhile, another Pacific Northwest project 鈥� the Cascadia Center for Sustainable Design and Construction 鈥� has been described as 鈥渢he world’s most energy-efficient office building.鈥�

Cascadia Center for Sustainable Design and Construction

Floors: six
Square footage: 45,000
Primary building material: timber framing
Prospective tenants: the Bullitt Foundation, the Cascadia chapter of the U.S. Green Building Council and the International Living Building Institute
Project team: Miller Hull Partnership, Point32, PAE Consulting Engineers, Schuchart Construction
Building life goal: 250 years
Completion target: summer 2012

Oregon Sustainability Center

Floors: seven
Square footage: approximately 135,000
Primary building material: concrete
Prospective tenants: Portland State University, retailers and others
Project team: GBD Architects, SERA Architects, Gerding Edlen Development, PAE Consulting Engineers, Skanska USA
Building life goal: 100 years
Completion target: August 2013

The projects, however, are not competing with each other so much as with the challenge of creating living buildings that won’t be occupied by their owners.

鈥淭he interesting thing about the Living Building Challenge is that you either meet it or you don’t,鈥� said Scott Clem of , the general contractor for the sustainability center. 鈥淭o say that one building is greener than the other is facetious.鈥�

The Cascadia center, scheduled to be completed in summer 2012, would be the first urban office building to meet the Living Building Challenge. The sustainability center, slated to be completed in August 2013, would be the first urban high-rise living building, according to Jill Sherman at Gerding Edlen Development. And at seven floors and approximately 130,000 square feet, it would be the largest and tallest living building.

鈥淲e think it’s great that somebody else in the region is trying to figure this out,鈥� Sherman said.

The Oregon Sustainability Center, originally planned as a 220,000-square-foot structure, has had to overcome significant hurdles relating to cost and public opinion. The center’s schematic design will need to be approved by the Portland Development Commission and Portland City Council before design development can proceed, hopefully this fall, Clem said.

Like all stakeholders striving to meet the Living Building Challenge, those leading the Portland and Seattle projects must take special care to avoid materials that contain harmful chemicals, detailed on the challenge’s 鈥渞ed list.鈥� Officials with both projects are in talks with manufacturers to find 鈥� or even specifically commission 鈥� materials that meet those requirements.

鈥淲e’ve got a pretty good database that we’re building that will vet materials contractors use, and we’re working with manufacturing to remove toxins,鈥� said Chris Rogers of Point32. He is working as a Cascadia center project manager.

A limited use of materials affects cost 鈥� a factor particularly important for buildings that will eventually offer leases.

In most cases, potential living building projects are community centers, nonprofits’ offices or private homes. Their owners typically absorb cost burdens and come to understand how net-zero energy structures and systems work.

鈥淲e’ve introduced the wrinkle of tenants that can change, need to be encouraged and controlled and monitored and that need to pay a rent that’s reasonable,鈥� Clem said.

The Oregon University System has mandated that construction costs for the Oregon Sustainability Center be less than $424 per square foot so that rents can remain competitive. The Oregon Sustainability Center is a $70 million project, according to recent numbers from the Portland Development Commission. Rogers would not give a cost estimate for the Cascadia center, but added that downward pressure on commercial rents and the expense of green construction were major challenges for the project.

Stakeholders in the projects justify large price tags with sustainability: The Cascadia center is expected to last 250 years, and the sustainability center is expected to last 100.

Tenants in the buildings will be required to adapt to energy needs to keep them net-zero, Clem said. If office tenants were to act as normal office tenants 鈥� such as maintain a regular office temperature, run many large appliances like copy machines, and rely on artificial lighting 鈥� he said, 鈥渁 lot of the (energy) strategies 鈥� are going to fail.鈥�

Tenants will sign 鈥済reen lease鈥� agreements to assure practices are employed that will keep energy consumption low. Also, energy use will be monitored.

In the Oregon Sustainability Center, lower-floor retail spaces will be open only to tenants who consume relatively less energy: no dry cleaners or bakers, for example, Clem said. Cascadia center tenants, on the other hand, are expected to be involved in the green building industry and naturally employ sustainable practices.

Neither of these buildings, when completed, will be expected to operate like normal buildings.

鈥淭his isn’t just a real estate project; it’s an economic development project,鈥� Sherman said. If a developer just wanted to build an office building that was profitable to rent, she added, this wouldn’t be the way to do it.