Some Reasons Why Buildings May Not Live Up to Green Labels

Recently The New York Times published an article entitled "Some Buildings Not Living Up to Green Label." The main thrust of the article was that a number of LEED buildings are not sufficiently energy efficient to qualify for the EPA's Energy Star Building label. The article addresses a few of the possible reasons for this disparity, one of which is that some LEED project teams "chase points" by incorporating as many inexpensive criteria as possible, rather than focusing on more capital-intensive energy management solutions.
A significant reason that LEED buildings are not meeting the Energy Star Building standard may be that Energy Star focuses chiefly on energy at the expense of other important characteristics of green buildings. The Energy Star rating system for buildings is a set of tools that enables building owners to evaluate their properties in relation to other buildings of the same type based upon energy consumption per square foot. The EPA does say that buildings should be tested for compliance with minimum acceptable standards for ventilation, thermal comfort and adequate lighting, but does not allow additional energy consumption for buildings that exceed those standards.
Here are some other reasons that I believe LEED buildings may not qualify as Energy Star Buildings:

• Energy Star rates buildings based upon energy consumption per square foot and does little to account for variation in occupant density. New buildings (including LEED buildings) often allow fewer square feet per person, and of course more people will use more energy. So an older building with large perimeter offices for executives could get a better Energy Star rating than a new LEED building with superior space optimization.
• Energy Star groups office buildings that operate at least thirty hours per week ten months per year into a single class for comparison, and often building modeling systems that predict energy use in buildings assume that most occupants will leave at about five or six o'clock. A number of LEED buildings in New York have considerably extended hours of operation, especially those housing law firms, publishing companies and financial institutions.
• Many LEED buildings have large expanses of glass from floor to ceiling. Glass between the level of the floor and approximately 30" above it introduces a lot of heat into an interior with very little daylight to compensate for the solar gain.
• One of the chief advantages of LEED buildings is enhanced indoor environmental quality. Increasing the level of ventilation and thermal comfort over that specified by ASHRAE standards and building codes benefits occupant health and productivity, but can result in higher electrical costs for HVAC than that of a less healthful building.
• LEED professionals jokingly say that the buildings are perfect until people start using them. Unfortunately, there's quite a bit of truth in that statement. Often building maintenance personnel, cleaning personnel and building occupants are not properly trained about the effective operation of the new building.
• Sometimes building systems do not perform as expected and initial commissioning does not address the problems adequately.

The EPA has acknowledged that Portfolio Manager is not always effective for urban buildings and promised a NYC specific overlay to support Greener, Greater Buildings legislative mandates. Hopefully, the new parameters will provide methods for addressing both our 24/7 work schedules and the high occupancy densities of all of our buildings.