Small Issue Costing NYC Building Owners Millions Annually

By Andie Lowenstein, Associate Editor

New York—Through the cold winter months, tall buildings act like chimneys—heat escaping through cracks and gaps in the roof and frigid air making its way through the bottom. The boiler runs overtime and so does your wallet.

A report titled Spending Through the Roof was released Wednesday by Urban Green Council, the New York affiliate of the U.S. Green Building Council, revealing if residential building owners simply plug open vents at the top of elevators shaft, they could save more than $11 million annually and cut annual carbon emissions by 30,000 metric tons.

As the report describes, the loss of hot air is caused by what’s known as the “stack effect.” Heat rises out of lobbies and escapes through roof vents, is then replaced by cold air from below, and boilers have to pump hot air to replace it. The rush of cold air is what makes it so hard to open lobby doors during the cold winter months. Heat is also constantly leaking through windows, gaps in masonry, and other quick-fix areas.

“Across the city, people are paying to heat the outside air. It makes no sense for them and it contributes to climate change,” said Russell Unger, Executive Director of Urban Green Council. “Fixing these open vents is an easy place to begin. But don’t stop there. Set your building staff on the problem and you’ll find countless other simple, inexpensive next steps to reduce air leaks and improve energy efficiency.”

The report says apartment building owners spend an average of $3,400 each year to heat air escaping through the roof. Heated air escapes at an astounding rate of a living room’s worth of warm air every minute. For taller buildings, this can be well over $20,000 every year. For years, the New York City Fire Department and New York State regulations required openings at the top of elevator shafts and stairwells in many tall multifamily buildings and hotels to improve fire safety by drawing smoke out of the building. Changes that later occurred in building construction and firefighting practice mean these vents are unnecessarily open all the time. However, a 2014 change to the New York City Building Code permits new solutions. The new code says the total vent area can be covered so long as the louvers will open upon detection of smoke, loss of power, or manual override. This requires electricity and access to the fire system, so the project must be supervised by a qualified engineer or contractor to be sure all code requirements are fulfilled.

Motorized, fully closing vent

This solution is best fit for larger, more sophisticated buildings. Assuming that 80 percent of tall apartment buildings have open vents, the amount of heated air escaping–somewhere between four and 16 percent per building–could fill 29,000 Empire State Buildings. The report found the cost per new vent can range anywhere from $5,000 to $15,000, depending on access to the systems and other site-specific concerns, but the payback period is short (approximately one to five years) and will save significant money in the long run.

The report arose in light of the de Blasio administration and New York City Council working to graph the route toward a very determined goal: an 80 percent reduction in greenhouse gas emissions by 2050. Building owners and managers are a crucial part of reaching that goal, and plugging vents and holes in the city’s nearly 4,000 multifamily buildings more than 10 stories tall is an easy way to start.

Spending Through the Roof was produced by Steven Winter Associates and funded by NYSERDA. A How-To-Guide and online savings calculator for building managers and operators is included as well.

Urban Green Council will hold a panel discussion on the findings and recommendations in Spending Through the Roof on April 23. The event is co-hosted by two groups involved in greening the city’s buildings: the Real Estate Board of New York and 32BJ SEIU, the city’s largest property workers service union.