Sustainable showcase

August 11, 2010

The new headquarters of the California Environmental Protection Agency (EPA) is notable for more than its abundance of 'sustainable' features. The manner in which the 930,000-sq.-ft. building evolved was also atypical. It was developed by a public entity, the city of Sacramento, for lease to the EPA. The state of California has a 25-year lease, with an option to purchase the property.

The California Department of General Services (DGS) selected the city's proposal from a field that also included about 10 developers. Each submittal consisted of a proposal for both a building plan and a building site. A major strength of the city's proposal was its plan to use a strategically located site it owns across the street from City Hall.

EPA worked closely with DGS to develop design criteria, according to Theresa Parsley, EPA's assistant secretary for facilities.

The building's sustainable features can be grouped into three general categories: Air quality; energy conservation and management; and recycling and recycled products.

Because offices housed in the building include those of the California Air Resources Board, which monitors air quality, EPA was particularly sensitive to indoor air quality issues, and especially to the detrimental impact of volatiles and aldehydes, Parsley says.

Floor-by-floor HVAC system

The primary contributor to good interior air quality is an innovative, floor-by-floor HVAC system. Unlike a standard system that is fed by central ducts, each floor of the EPA building has at least two air intakes. Tower floors (nine through 25) have two mechanical rooms, and the first through eighth floors have three or more. Fan rooms, located at the northeast and northwest corners of the building, are positioned to prevent cross-contamination, which could occur if exhausted air is drawn back into the building. During the night, the building is flushed with outside night air, generally for at least five hours.

A lower noise level and reduced duct pressures are other advantages of the individual floor air distribution system compared to a central system, according to Anil Shenoy, president of the building's Santa Monica, Calif.-based mechanical engineer, Levine Seegel Associates.

The building was designed to be 30 percent more efficient than required by California's Title 24 energy code. However, Shenoy believes an analysis of operating data will show a performance that is about 40 percent better. This is a result in part of the use of dual glazing with a low-emissivity coating. Energy performance is also enhanced by varying the amount of exterior glass, which is used most extensively on the north wall. Precast concrete panels on the south and west sides of the building have integral sun shades.

Energy-saving building orientation

David Martin, project designer with architect AC Martin Partners, emphasizes that the building's north-south orientation plays an important role in its efficient energy performance. 'Because EPA was to be the tenant, we were as sensitive as we could be with respect to energy conservation,' Martin says. Another objective of the design was to accommodate the building's massing so it does not detract from Sacramento's historic City Hall across the street.

Electric use for lighting is 0.9 watts per square foot as compared with 1.2 watts per square foot mandated by Title 24. Each workstation has a task light connected to a motion detector. The light is turned on when the station is entered, and off when an occupant leaves.

Electrical use is monitored both on a floor-by-floor basis and according to whether it is used to operate the mechanical system, lights or power outlets. It is thus possible to check the performance of particular equipment. Computers with a reduced electrical requirement were installed on two floors, for example, and readings on those floors were compared with those for floors with less efficient computers. 'We're validating that systems do what they're claimed to do,' Parsley says.

VOCs banished

Interior finishes that do not contain volatile organic compounds (VOCs) were specified. Parsley says the only negative feature of non-VOC-containing paint discovered so far is that it appears to have a short shelf life - a disadvantage when it is stored for future maintenance use.

EPA had more than an academic interest in learning about the products used in its headquarters. 'We're a regulatory agency,' Parsley explains. 'Before we apply regulations, we want to find out how the products perform.'

Carpet tiles used in the EPA building have a recycled content of 53 percent. ('You can get a 100 percent recycling content if you want to go ugly,' Parsley notes). The 18-in.-square tiles have a sticky backing that does not require glue for application. Another factor that was considered in awarding the carpet tile contract to Collins & Aikman was the company's pledge that any returned used tiles would be recycled, and not placed in landfills, according to Parsley.

In some instances the recycled product proved to be less expensive than the virgin material version. This was the case, for example, for an 82 percent recycled content ceiling tile that has the same noise reduction property.

Although the procurement of sustainable components required planning, it did not hinder the construction schedule, says Terry Richards, project executive with general contractor Turner Construction Co. 'If you need 770,000 square feet of carpeting, you can quickly tax a manufacturer's production capacity,' he notes.

'The developer brought expertise in knowing how to buy a job, and how to get it designed right - in keeping the numbers competitive and the quality high,' Richards says. 'The result is a building of private-sector quality for a public-sector client.'

Richards says the bidding process was basically a private-sector process, with some public sector requirements. This meant that bidders could be prequalified to eliminate 'essentially lump sum, low bid entities.'

Sustainable features added

'We worked with DGS to put together what we considered an appropriate budget,' says Mike Smith, senior vice president with Thomas Properties Group, the project's Los Angeles-based development manager. He directed the building's core-and-shell construction. Thomas held the design and construction contracts, and Turner held the construction subcontracts.

Gino Polizzotto is the Thomas Properties construction manager who directed the tenant improvement portion of the project. He says that after the project was announced in the mid-1990s, EPA decided that it wanted more sustainable features than were specified in the minimum performance criteria. 'We had started design development, and also began incorporating items written into the lease that required a higher level of performance than what we originally bid on. We were able to deliver most of everything EPA wanted, on time and for the original budget.' Polizzotto attributes this accomplishment to both an aggressive buyout and a favorable market.

Thomas Properties Group, a separate but related organization, manages the building. It was awarded a contract after the city waived its right of refusal to self-manage the property.

 

CONSTRUCTION COSTS

Core and shell $82,000,000
Site work 2,950,000
Off-site park improvement 1,000,000
Tenant improvements 29,750,000
TOTAL $115,700,000

 

 

         
 

Comments on: "Sustainable showcase "