Concern mounts over emissions goal.

Mayor Michael Bloomberg's recent announcement of short-term measures the city will take to reduce greenhouse gas emissions coming from municipal buildings proves he is stepping up efforts to make good on his promise to reduce carbon dioxide emissions coming from the city's controlled buildings by 30% by 2017, as outlined in plaNYC.

Yet builders have begun to express concern whether expensive retrofits of old buildings in the private sector could be mandated in the future to make good on the second part of that plan, which promises a further 30% reduction in all emissions coming from the city by 2030.

Builders, architects and engineers broaching the idea of beginning the process of retrofitting their buildings now to make them more energy efficient are also beginning to wonder how viable it is to go green.

"The concept of reducing greenhouse gas emissions from the city is excellent. The stone cold facts are that it can be extremely difficult and very expensive for an architect or an engineer to retrofit an old building to be energy efficient," said Dr. Mark S. Laska, president and ceo of Great Eastern Ecology, a unique ecological consulting firm based in Manhattan.

"So one of the questions I would pose, what is still unresolved, is what kind of enforcement muscle that will be put behind this in the future. How the Buildings Department will choose to regulate and track the reduction of emissions."

The first phase of the short-term action plan includes 132 projects throughout all five boroughs and that is expected to reduce greenhouse gas emissions by an estimated 34,000 tons annually. Smaller builders can learn from some of these examples and find less expensive ways to be more efficient while cutting costs. Energy fixes, such as removing inefficient lights and appliances and replacing them with more energy efficient ones, can be done gradually and still have an effect, Laska said.

Others are just as confident but stress that brainstorming and planning in the private sector must begin in earnest sooner rather than later.

"The question we now have to ask is, now that we know what the problem is, what are we going to do with these millions of square feet of buildings in the city that just don't measure up," said Tony Daniels, associate at Cycle Architecture during a recent New York Industrial Retention Network forum about green contracting. "We need to find a pool of people who are skillful in retrofitting buildings, who need to be able to tell us what the best way to retrofit that inefficient curtain wall without wasting all our resources experimenting."