Few tenants, however, are willing to accept the daily presence of a cleaning crew during business hours, says Madeleine Abel, vice president of property management at Rockville, Md.-based BECO Management Inc. Abel is a volunteer leader in charge of green initiatives at the Institute of Real Estate Management, a Chicago-based trade group.

An offshoot of daytime cleaning is gang cleaning. Everyone from floor buffers to trash collectors operate as a group, one floor at a time in a rolling fashion. That enables managers to turn off all but emergency lighting and climate control except on the floor being cleaned. The practice reduces power consumption to a fraction of the cost of operating the entire space.

At the EPA regional headquarters in Denver, Smith suggests that property managers introduce daytime cleaning gradually. “If most of your tenants are gone by 6 p.m., don't wait until 8 p.m. to bring your janitors in,” she says. “Bring them in at 5:30 so they can be ready to rumble at 6.”

Over time a landlord can introduce daytime cleaning as leases renew. “You're getting your janitorial crew in earlier and earlier,” Smith says. “Eventually you'll have 100% daytime janitorial.”

Movement to mainstream

Some of the most effective property management practices, such as floor-by-floor heating and cooling during periods of reduced building use, aren't possible in older buildings without costly upgrades.

To encourage building owners to make those changes where necessary, the Building Owners and Managers Association (BOMA) has been working with the Clinton Climate Initiative to establish easier ways to tackle retrofits.

President Bill Clinton launched the Clinton Climate Initiative in 2006 to help cities and organizations reduce practices that may harm the environment. Brenna Walraven, managing director of national property management at USAA Real Estate Co., is heading BOMA's partnership with the Clinton Climate Initiative. The key, she says, is to keep the cost of green property upgrades in line with the savings.

For example, an energy service company replacing the HVAC system at an office complex guarantees via an energy performance contract that the landlord will save $100,000 annually in power costs. Rather than bill the building owner for the $540,000 project in a lump sum, the service provider agrees to take $90,000 in payment each year for six years, provided it performs as expected.

If the new system doesn't deliver the promised savings, the contract delineates how the service provider will compensate the property owner for the shortfall.

That's the sort of cost-effective approach to sustainability that building owners and managers are looking for, Walraven says. “Fundamentally, green is about being efficient and eliminating waste,” she says. “It should cost you less, not more.”

The U.S. Green Building Council hopes more landlords implement and maintain sustainable management practices such as those measured in the Leadership in Energy and Environmental Design for existing buildings program, or LEED EB.

In fact, LEED EB is all about maximizing the efficiency of a building — no matter the age — without major renovation. Conversion of an existing structure to conform to the latest green building standards falls under LEED for new construction rather than LEED EB, according to Marc Heisterkamp, director of commercial real estate for the council.