A quarter of the new buildings that have obtained LEED certification do not save as much energy as they claim and most do not track energy consumption once in use, writes MIREYA NAVARRO

Builders covet LEED certification - it stands for Leadership in Energy and Environmental Design - as a way to attract tenants, charge premium rents and project an image of environmental responsibility.

However, the research conducted by the United States Green Building Council (USGBC) non-profit organisation that administers the LEED programme, suggests that a quarter of the new buildings that have been certified do not save as much energy as their designs predicted and that most do not track energy consumption once in use. And the programme has been under attack from architects, engineers and energy experts who argue that because building performance is not tracked, the certification may be falling short in reducing emissions tied to global warming.

The USGBC has now announced that that it would begin collecting information about energy use from all the buildings it certifies.

Mandatory

Buildings would provide the information voluntarily, said officials with the Council, and the data would be kept confidential. But starting this year, the programme also is requiring all newly constructed buildings to provide energy and water bills for the first five years of operation as a condition for certification. The label could be rescinded if the data is not produced, the officials said.

Some experts have contended that the seal should be withheld until a building proves itself energy efficient, which is the cornerstone of what makes a building green, and that energy-use data from every rated building should be made public.

Scot Horst, the council’s senior vice president for its certification programme, said that any changes in the process would have to be made by consensus to ensure that the building industry would comply.

Already, some construction lawyers have said that owners might face additional risk of lawsuits if buildings are found to under performMr. Horst called the issue of performance one of his "absolute priorities." "If you’re not reducing carbon, you’re not doing your job," he said.

The LEED label, developed by the council in 1998 to have a third-party verification of a building’s environmental soundness, certifies new homes, schools and other buildings, as well as existing ones. (The certification for existing buildings is the only one currently tied to energy performance.)

Its oldest and largest programme, in terms of square footage, is the certification of new commercial and institutional buildings, with 1,946 projects already certified and 15,000 more that have applied for certification.

Many other buildings include environmentally friendly features and advertise themselves as "green" but do not seek the LEED label.

Point system

The programme uses a point system based on a broad checklist of features and buildings can be certified by accumulating points on not just efficient energy use but also water conservation, proximity to public transportation, indoor air quality and use of environment-friendly materials.

Council officials say that these other categories also help reduce energy use and emissions. And many architects and engineers praise the comprehensiveness of the label. But the wide scope of the programme, many in the industry point out, also means that buildings have been able to get certified by accumulating most of their points through features like bamboo flooring, while paying little attention to optimising energy use.

Another problem is that the certification relies on energy models to predict how much energy a planned building will use, but council officials and many experts agree that such models are inexact.

Once a building opens, it may use more energy than was predicted by the design. And how a building is used - how many occupants it has, for example - affects its energy consumption.

"If the occupants don’t turn off the lights, the building doesn’t do as well as expected," said Mark Frankel, technical director for the New Buildings

Institute, which promotes improved energy performance in new commercial construction and conducted the research commissioned by the Green Building Council on LEED buildings.

"In the real world, the mechanical systems may have problems, so that increases energy use," Mr. Frankel said, adding that keeping track of energy use is rarely a priority for owners.

The LEED standard goes through periodic revisions, and this year, the minimum energy requirements needed for the basic LEED certification for new buildings were raised. But in its own study last year of 121 new buildings certified through 2006, the Green Building Council found that more than half - 53 percent - did not qualify for the Energy Star label and 15 percent scored below 30 in that programme, meaning they used more energy per square foot than at least 70 percent of comparable buildings in the existing national stock.

Mr. Horst, the LEED executive, said that LEED may eventually move toward the E.P.A.’s Energy Star model, which attests to energy efficiency only for the year the label was given, similar to restaurant ratings.

"Ultimately, where we want to be is, once you’re performing at a certain level, you continue to be recertified," Mr. Horst said.

The New York Times News Service

Keywords: LEEDgreen buildings