By Brian Redlein
It must be said, that the single biggest item holding up new building approvals at DOB these days seems to boil down to one word: Energy.
With greater awareness of human impact on global climate in recent decades, many building regulators throughout the United States began to realize that buildings contributed nearly a third of greenhouse gasses to the atmosphere and that something needed to be done about it.
A building’s energy load can currently be measured in four separate categories: envelope, lighting, mechanical systems, and hot water systems. Envelope determines how well a building holds its heat in winter or how badly it loses it’s cool in summer. Lighting dictates how efficient bulbs and fixtures can be in a building, mandating specific lumen outputs for a given amount of wattage. Mechanical determines minimum energy efficiency ratios (EERs and SEERs) that air conditioning equipment must comply with. Hot water systems are far more basic and largely hinge on insulation provided for hot water pipes and tanks. Together all four make up a complete Energy Analysis which is required to be completed in full to permit a new building.
While being green is in fashion, much of what the industry used to consider optional is fast becoming mandatory. Glass buildings under the 2014 New York City Energy Conservation Codes are required to perform costly energy modeling on all building systems now if their fenestration area exceeds 40% clear glass.
Each update of the Code makes it harder and harder to find a packaged through-wall air conditioning unit that actually complies with its mandated SEER / EER ratio and increasingly encourages robust split AC systems that are far more costly. With the city currently placing maximum focus on building energy loads with an eye towards cutting emissions by 80% by 2050, it gets more and more difficult to get buildings to pass the energy code particularly as it relates to the building envelope.
Energy savings always begin with a building’s skin and orientation towards the sun. Put a lot of glass on the south façade for example, and your mechanical engineer will soon be working overtime to design an AC system capable of removing the heat generated as the sun’s rays hit the interior. For the economic architect, punched windows in heavy masonry facades featuring continuous “blue foam” insulation is now typical and EIFS, where the insulating foam is affixed to the outside of the building and covered in fake acrylic stucco, will be more in vogue than ever.
Those with money to burn may increasingly look towards heavy fitting of glass, expensive double façade systems, and advancements in Aerogel and Vacuum Insulated Panels (VIPs) for their energy saving needs.
The costs of a building will be increasingly effected by the need to minimize energy load and the earlier architects engage engineers and ownership to come up with solutions, the better. Energy can no longer be an afterthought. Designers and developers in NYC who place energy on the backburner of priorities now do so at their own peril.