After construction, the team submits project documentation that includes product information, energy modeling and construction waste disposal records. The council then scores the project on a scale of 69 points. Four ratings are possible, from certified, which requires 26 points, to platinum, which requires 52.
There are 1,772 registered projects, representing about 5% of construction starts in the U.S., says USGBC. Another 167 buildings have become certified.
Learning Curve
The systems users say the process requires more time and effort at every project phase. How much additional time depends on the experience of the team.
One Seattle-area contractor estimates that its first LEED building required some 400 hours to document. Now working on its third registered project, the contractor says the documentation required about 20 to 40 preconstruction hours, approximately five hours each week during construction and another 20 or 30 hours to prepare for final submittal. "The requirements do not justify additional staff," says the executive.
The requirements sometimes translate into additional fees for consultants. Tim McGinn, principal of Keen Engineering, Calgary, says that for a hypothetical $14.5-million project, services like facilitating a design charette, energy modeling and commissioning could add about $78,000 to mechanical fees. The expense can often be mitigated by grant or incentive programs, he points out.
Other designers say additional fees can be a hard sell. Robin Guenther, principal of Guenther 5 Architects PLLC, New York City, suggests an alternativea design that meets LEED performance goals could be considered part of standard practice. But compilation of the application and documentation should command an extra fee. "Then the owner makes a clear decision that the process is worth something," she says.
 |
|
More Point Potential? Energy modeling discrepancy made diagnostic and treatment center's energy efficiency seem artificially low. (Photo courtesy of Guenther 5 Architects PLLC)
|
Although users are convinced of the systems value, many complain that the fit for building types other than offices is sometimes awkward because LEED was conceived with office buildings in mind. Deviation from any particular points set standards requires obtaining a credit interpretation from the council.
University buildings, for example, "are a different animal," says Steve McDowell, principal of BNIM Architects, Kansas City. The firm expects a gold rating for its School of Nursing at the University of Texas Health Science Center. The Houston building was completed in October. But at one point, even a certified rating was in doubt. The building depends on an existing central chiller that uses a refrigerant prohibited by LEED. The owner and the council were able to work out a refrigerant change-out schedule. But without that agreement, "the issue could have been a deal breaker," says McDowell.
A credit interpretation also was necessary to permit smoking in a residential tower that New York City developers the Durst Organization and Rose Associates are building in Manhattan. LEED requires buildings to be smoke-free, or requires the separation between smoking and non-smoking areas comply with a standard intended for laboratories. That is a high bar for an apartment building.
Some industry design standards cited in LEED are not an accurate reflection of performance, say users. One example is the problem encountered by...
...categories: sustainable sites, water efficiency, energy and atmosphere, materials and resources, indoor environmental quality and innovation and design.
