Climate change
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The New York City Climate Mobilization Act (CMA) demands more in energy efficiency from buildings

Todd Kimmel, Certified Passive House Designer, Regional Specifications Manager, ROCKWOOL.
Todd Kimmel
13 June 2019

The new legislation requires that any building 25,000 square feet or larger will need to reduce their greenhouse gas emissions by 40 percent by 2030 from a 2005 baseline, increasing to an 80 percent reduction requirement by 2050.

New York City skyline with Manhattan skyscrapers at dramatic stormy sunset, USA.

NYC climate mobilization act requires renewed green building requirements for construction and renovation projects to support building energy efficiency and ultimately, climate change.

New York City gets to work as Climate Mobilization Act (CMA) passes

New York City produces over 50 million tonnes of carbon dioxide a year, more than half of which comes from its own buildings which are the leading carbon emissions sources in the city. Now, the Big Apple will be undergoing big changes in light of the city’s new legislation – the Climate Mobilization Act.

Passed by the New York City Council, this set of bills will enact significant changes to New York’s energy efficiency efforts by setting carbon emission caps for many of the city’s monumental and historic buildings (including Trump Towers and the Empire State Building) in the interest of sustainability. These caps will significantly reduce the city’s carbon emissions, including greenhouse gas emissions, nitrogen oxides, sulfur oxides, and other particulate matter.

The Climate Mobilization Act is a welcome addition to New York’s climate action plan in ensuring a cleaner, healthier environment for all current and future New Yorkers. It will also stand as an example for other cities looking to create their own climate justice movement in fighting climate change. In total, it will affect almost 60 percent of the city’s current building stock, amounting to 50,000 structures.

In New York City, the climate crisis is not only of grave concern with the current infrastructure and building stock but also as it relates to the city’s population which is at a record high. Projected to surpass 26 million by 2050 from its 23 million regional population today, new housing construction has reached its highest levels since the 1960s and the high-density growth is fueling the need to ensure that the city’s growing population and strong economy remain foundational to meeting future aspirations.


Instead of building owners having to meet ever-changing energy requirements that are updated every few years with every code cycle, this bill sets a clear target and lays out a pathway to get there.

Stas Zakrzewski

Principal, ZH Architects and Vice President of New York Passive House (NYPH)

Climate Mobilization Act demands more in energy efficiency

Included in the legislation are three key bills that offer valuable energy-efficiency solutions in terms of heating, cooling, and renewable energy capture and usage, all focused on reducing air pollution. 

Bill 1253 (Local Law 97 of 2019) will require existing buildings to meet the specified requirements by retrofitting energy-efficient upgrades including windows, smart HVAC systems, and other energy-conserving construction products. This bill also announces the city-wide commitment to achieve certain reductions in greenhouse gas emissions by 2050. To provide some relief to building owners, Bill 1252 will establish a sustainable energy loan financing system titled the Property Assessed Clean Energy (PACE) program that provides renewable energy credits and emissions offsets for installations or improvements made. Bill 1032 (Local Law 94 of 2019) introduces changes to New York green roof requirements (green roofs are those covered in plants), applicable to all new buildings, building expansions and structural roof work. The intention of the bill is for all available roof space to be covered in green or cool roofs, solar, or both, with the installations required for residential or commercial buildings that meet a variety of occupancy group criteria within the New York City building code. 

According to the Energy Efficiency for All New York Coalition, the Climate Mobilization Act will generate thousands of construction jobs, and lower operating costs once new measures are in place. Legislators have also embedded flexibility within the program to support green building in NYC. There is an up to 100 percent deduction offered from annual emissions limit for the purchase of credits for renewable energy in NYC in addition to deductions available for the purchase of greenhouse gas offsets (up to 10 percent) and peak energy storage for 2024-2029 limits.

The ground-breaking legislation is a clear indication of New York City’s support for the climate change movement and will be rolled out with a gradual build toward increasingly stringent CO2 emission limits as outlined below, as the city works toward net-zero building design and construction on future infrastructure projects.

  • 2021 – Adjustments deadline for buildings >40% over 2024 limits with special circumstances 
  • 2023 – Rules and metrics due for emission limits and factors in 2030 and beyond
  • 2024 – Emissions limits begin 
  • 2025 – NYC government emissions must be 40% below 2006 baseline 
  • 2030 – NYC government emissions must be 50% below 2006 baseline

Many buildings are significantly above the new green building emissions limits and will require comprehensive retrofits or alternate compliance by 2030. See below for a series of visuals providing you with an overview of the impacted built environment.

new-york-city-emissions-law-combined-green-building-requirements-graphic of Climate Mobilization Act as new legislation supporting climate change gets approval from NYC.

The Climate Mobilization Act is impacting nearly 60 percent of New York City's buildings and currently only 25% of properties meet the aggressive climate change and green building requirements for 2030.

climate-mobilization-act-emissions-law-impacts-nearly-60-percent-nyc-building-area as new green building requirements legislation supporting climate change gets approval.

Nearly 60 percent of existing NYC buildings are impacted by the new Climate Mobilization Act legislation.

nyc-buildings-25-percent-below-2030-emissions-law-limits of Climate Mobilization Act as new green building requirements legislation supporting climate change gets approval.

Only 25 percent of NYC buildings today meet the new green building requirements and emissions limits for 2030.

This law sets tough requirements for buildings to reduce carbon emissions. But it does so with innovative policy approaches that make it possible.

John Mandyck

CEO of Urban Green Council
Download Urban Green Council's legislative summary

NYC takes a stronger stance on reducing carbon emissions

Finding ways to reduce greenhouse gas emissions from New York City buildings has been a challenge for years. Over the last decade, there has been little effort to incentivize building owners to find ways to cut energy use. According to the Climate Works for all Coalition Report, past programs were not successful because they were focused on limited building updates.

The Climate Mobilization Act is pushing more aggressive and ambitious legislation both for new construction and building renovations or retrofits, in an effort to achieve climate restoration. As NYC energy consumption climbs (New York City buildings contribute to nearly 70 percent of New York’s carbon emissions), the city chose to address those buildings mentioned earlier that fulfill the criteria of being greater than 25,000 square feet, which are responsible for 30 percent of the city’s total carbon emissions.

Setting carbon emission caps along with other legislation is one of the biggest and most ambitious climate restoration initiatives to come to fruition and some of the ways to reduce carbon emissions globally as we’ve seen in other cities, states, and regions.

To date, NYC has made some headway in the positive direction on reducing greenhouse gas emissions. The graphic below outlines New York City when compared to the global trend.

Energy efficiency is a worldwide initiative

Case studies in reducing greenhouse gas emissions

California has implemented their plan to reduce greenhouse gas emissions due from large electric power plants, large industrial plants, and fuel distributors by more than 16 percent between 2013 and 2020, and by an additional 40 percent by 2030. Washington DC has also set aggressive CO2 emission-reduction targets using 2006 as a baseline and 2032 as the target year to begin enforcement, with buildings serving as the center point of the program.

California has also approved a research project to investigate and develop an alternative prescriptive compliance path for homes certified under the Passive House Standard. The objective of this research includes determining whether buildings built to the Passive House Standard could satisfy requirements under the 2022 California Energy Code.

Visit the California energy codes and standards to learn more.

new-york-city-reducing-greenhouse-gas-emissions as part of the Climate Mobilization Act green building requirements legislation supporting climate change.

New York City is making significant strides to reduce greenhouse gas emissions through new green building legislation and passive house design and construction practices while global emissions continue to rise.

New York City has taken a very aggressive approach to combatting climate change. As buildings in our dense metropolis contribute the bulk of our carbon emissions, making a substantial reduction of impact can only occur if we address the energy performance of our buildings (new and existing alike).

Todd Kimmel

Certified Passive House Designer, Regional Specifications Manager, ROCKWOOL

Programs helping drive climate change in New York City

The climate action movement aligns with New York’s OneNYC 2050 program, designed to help the city lead the way in dealing with climate change. This program has implemented a $20 billion climate resiliency strategy to protect New York and its residents from global warming.

The OneNYC 2050 strategy outlines 30 strategic initiatives that the city will undertake to achieve their vision of addressing climate change, increasing unaffordability, and failing infrastructure, including:

  • Committing to carbon neutrality by 2050 by being a leader among global cities pursuing step cuts in greenhouse gas emissions
  • Leading by example on climate change (i.e. ending city purchases of unnecessary single-use plastics)
  • Reclaiming streets to meet the needs of the public by creating People Priority Zones that help improve air quality

Additionally, the not-for-profit organization The Climate Mobilization has been working to influence local governments and other organizations to adopt shorter timelines to combat the climate change emergency and reverse global warming. 

The American Cities Climate Challenge Renewables Accelerator is another ambitious initiative that will help U.S. cities achieve renewable energy goals. Through this program, cities are looking at ways to utilize higher percentages of clean and renewable energy.

The NYC Retrofit Accelerator is a comprehensive resource for building owners and operators looking to upgrade their properties through energy-efficient and water-efficient measures. Building owners can also purchase energy from renewable resources for more flexibility in complying with the new act.

NYStretch Energy Code-2020 established the residential code, Section R408 Passive House, as an alternative compliance path to be voluntarily adopted by any local municipalities in New York State. This legislation may serve as a potential path forward for other states.

Andreas Benzing

Principal, A.M. Benzing Architects and President of New York Passive House (NYPH)
See the NYStretch Energy Code-2020

New York sustainability: giving the green light on green construction

It’s time for architects, designers, building owners and community members in NYC to think about green living and green architecture. Building owners who fail to meet the requirements of this legislation can face fines as high as millions of dollars.

Whether constructing from the ground up or renovating existing buildings, each has its own set of benefits and challenges. Designing structures with energy efficiency in mind can sometimes put limitations on design freedom and flexibility, but it means they are built for long-term sustainability.

Building renovations or building retrofits of existing structures can be costly and inconvenient, for occupants, however, the opportunity is to minimize the waste produced by new construction and integrate new energy-saving approaches into the building.

The adoption of the new CMA legislation reinforces NYC’s commitment to achieving a reduction of carbon emissions 90% by 2050. This must happen. It’s exciting to be in the heart of it all with the eyes of other major cities watching and preparing to do something similar.

Todd Kimmel

Certified Passive House Designer, Regional Specifications Manager, ROCKWOOL

Passive house building standards inspire comfort without compromise

New York City is already starting to implement high-performing and energy-intelligent solutions through passive house construction. Passive House is a building concept that is geared toward achieving superior energy efficiency and comfort for occupants. Using Passive House standards and principles reduces 90 percent of heating and cooling energy and up to 75 percent of primary energy usage from standard building construction.

The House at Cornell Tech, one of New York’s largest and tallest buildings constructed to Passive House standards. Strict limits were placed on energy use for heating, cooling, and thermal comfort, so the approach was to use stone wool insulation and stone wool products in the design of the building. It is estimated that the House at Cornell Tech will save 882 tonnes of CO2 emissions per year. Even many multi-family residential buildings in New York City are being built and retrofitted to “passive house” standards.

In 2017, Handel Architects were chosen by the New York City government to design a 37-story Passive House apartment building on city property in East Harlem. Passive home design is becoming an attractive option for many because it requires no active heating or cooling equipment, such as energy-draining air conditioner units or radiators, for the interior to maintain a comfortable temperature, and uses about one-quarter of the energy of a typical home.

NYPH members have presented the Passive House concept to community boards throughout the city. To date, this has resulted in a Manhattan and Brooklyn Borough President resolution in support of Passive House. The local achievements have supported the state efforts to emphasize the importance of the Passive House concept as an alternative performance compliance path.

How does ROCKWOOL support green building and passive house construction?

ROCKWOOL has a history of supporting green building standards and practices and this legislation is no exception. From the early days of discussions on the Green New Deal in New York City which came to be known as the Climate Mobilization Act when it was passed on a 45-2 vote, we were open about the need for carbon reduction efforts. We believe that this package of bills will have a significant impact on air quality in the city and provide stronger protections for sensitive populations including children, the elderly, and asthmatics.

As a founding member of the Building Energy Exchange (BE-Ex), we are also driven by the opportunity to connect New York City’s real estate and design communities around the common goal of reducing the effects of climate change by improving the built environment. BE-Ex helps to accelerate the transition to healthy, comfortable, productivity and energy efficient buildings by serving as a resource and trusted expert to the building industry.

ROCKWOOL (previously ROXUL Inc.) has been a sponsor of New York Passive House since 2014, and an active champion of high-performance building standards and the passive house movement in New York for the past 10 years.  Our work includes advocating for more stringent environmental regulations and helping to expand the conversation surrounding the built environment.

We are dedicated to helping minimize the environmental impact from buildings using our stone wool products which contribute toward green building certification. Creating sustainable buildings means supporting healthy, highly efficient and cost-saving green buildings during the design, construction, operation, and maintenance of these high-performance structures.

Through concepts like Passive House design and construction, and new legislation like the Climate Mobilization Act, we can help to limit our carbon footprint in New York City and places across North America as we continue to find solutions in building a brighter future for all. 

Supporting the North American Passive House Network (NAPHN)

When the NAPHN looked closely at where the most activity and Passive House standard adoption was happening, they found that these green building practices are beginning to accelerate. Research showed that Passive House ‘bright spots’ aligned directly with locations where policymakers and practitioners were actively cooperating and collaborating.

We should require 2050 carbon emissions caps on all new construction immediately. If we don’t do that, we’re essentially building poorly-performing buildings now that we’ll be stuck with for the next 30, 50, 100 years and then it becomes economically less attractive to renovate new buildings to meet the new energy standards and greenhouse gas emission caps.

ROCKWOOL Sustainability Team Member

Download the fact sheet

Todd Kimmel

Todd Kimmel, CPHD (Certified Passive House Designer), CDT, is the New York City Architectural Manager for ROCKWOOL Insulation. Todd has over 18 years of technical experience working on building enclosures and façade systems. This includes the management and oversight of large-scale commercial building enclosures, working as the product and technical manager for Trespa® North America, and as a Technical Consultant for Dörken Systems. Todd is a Construction Documents Technician (CDT), a Certified Passive House Consultant (Passive House Institute) and currently sits on the board for New York Passive House (NYPH). He holds a Bachelor of Science Degree in Civil Engineering from Northeastern University and a Master’s Degree in Urban Planning from New York University’s Wagner School of Public Service.

Andreas M Benzing

Andreas M Benzing is the founding member of A.M. Benzing architects PLLC. He received a Master of Science in Architecture from the Bauhaus University Weimar and a Master of Design & Management from the Politecnico di Milano.  Andreas is licensed to practice architecture in New York State and in Germany. He is a LEED Accredited Professional, Certified Passive House Designer and a Building Performance Institute Certified Building Analyst and Envelope Professional.  He is a founding director and President of NY Passive House – a non-profit organization to promote the Passive House standard for a healthy, comfortable and energy-efficient built environment. Andreas has been appointed by the Manhattan Borough President to serve on Manhattan’s Community Board 5 and was appointed by the DOB Commissioner to serve on the 2015 and 2019 NYC Energy Conservation Code Advisory Committee. Andreas teaches Environmental Technology and Design Studio at The New School.