Certifying a swath of retail stores, a hotel chain or even a portfolio of existing office or industrial buildings under the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) program just got a little easier.

Developers and property owners now have the option of pursuing LEED for several properties at once through a streamlined process called volume certification. Applicants work with the U.S. Green Building Council to establish a prototype that meets LEED standards, so that properties developed or retrofitted according to that prototype can be certified more quickly than a one-off project.

Each property must be individually certified for LEED, but that certification process is carried out largely through the developer’s own quality control reporting and through spot checks by an inspector for the U.S. Green Building Council. Project components that will be used throughout the portfolio or chain — such as water fixtures, paint or carpet — need only comply with standard criteria established in the approved prototype or pilot project to help meet LEED requirements.

“This isn’t a different rating system,” explains Marc Heisterkamp, manager of corporate and investment real estate at the U.S. Green Building Council. “It’s really a streamlined process that helps us achieve our existing rating systems on a greater scale.”

One of the program’s pioneering participants, Wachovia, is using volume certification to develop more than 300 regional banking centers in accordance with LEED for retail standards by 2010. Wachovia’s architect, Seattle-based Callison, designed the bank’s new green prototype and had it pre-certified by the U.S. Green Building Council.

While each branch bank must still go through a certification process to achieve LEED for retail, Wachovia can build with the confidence that those properties will qualify for certification so long as they stick to specifications and procedures established in the prototype. “This results in an efficient, streamlined process for building sustainably on a large scale, thus saving time, money and manpower for retailers that want to go green,” says Chris Hamilton, a principal at Callison.

So far, the U.S. Green Building Council has pre-certified seven applicants that plan to apply for LEED on multiple buildings, and several more applications are under review. In all, the organization had 40 participants in its portfolio program as of late August, including companies, government agencies and universities. The portfolio program isn’t limited to building owners, but includes property managers and other companies that agree to incorporate sustainability into their standard practices.

Among the developers and property owners in the portfolio program is Starwood Hotels & Resorts Worldwide, which has committed to seek LEED certification for all of its new Element hotels. The first Element Hotel opened this summer in Massachusetts and the hospitality giant plans to open more than 20 around the globe by the end of 2009. Green components at Element hotels range from sustainable construction materials to low-flow water fixtures, high-efficiency climate-control systems and eco-friendly supplies used in daily hotel operations.

Even without participating in the U.S. Green Building Council’s portfolio program, developers can reduce the costs of building a chain of green properties by refining their development procedures as they build each property, according to Wen Chang, president and founder of San Francisco-based Atman Hospitality Group. Chang is developing what he says will be a global chain of LEED gold-certified hotels.

Branded under the moniker of Gaia — Greek for Mother Earth — the chain includes the Gaia Napa Valley Hotel & Spa in American Canyon, Calif., and the Gaia Anderson Hotel & Spa, just south of Redding, Calif. Chang is nearing completion of his third hotel, this one in Merced, Calif., a short drive from Yosemite National Park.

Chang estimates that his Napa Valley hotel cost 15% more to develop than a conventional, non-green property of the same size, but much of that premium stemmed from trial and error as the company nailed down its ideal for a sustainable hotel. The project went through 87 change orders before reaching completion.

For his second hotel, Chang established a team to coordinate the design, materials and suppliers for the project and reduced the hotel’s green premium to about 6% over conventional development costs. With the latest project in Merced, he says, that extra cost is about 3% more than non-green construction. Costs for green-building materials also have come down as new suppliers and products have entered the market, Chang says, but sticking to a well-orchestrated plan eliminates many unnecessary expenses and has helped to lower his costs considerably.

“Try to put together the LEED team or the green team as early as possible and that will save a lot of trouble,” he says. “And select the right captain for the consulting team. It has to be under one person.”