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Your Guide to NYC Local Law 97 for Sustainable Building

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What is Local Law 97?

Local Law 97, part of New York City’s Climate Mobilization Act, requires large buildings – those over 25,000 square feet – to reduce emissions by 40% by 2030, and 80% by 2030.

The law sets specific emissions standards for “covered buildings”, which are those (1) that exceed 25,000 gross square feet or (2) two or more buildings on the same tax lot that together exceed 50,000 square feet, or (3) two or more buildings held in a condominium form of ownership that are governed by the same board of managers that together exceed 50,000 gross square feet.

Different building types have different emissions limits – We’ve included tables below that summarize building typology and the accompanying emissions limits provided by New York Engineers. The law itself spells out relevant calculations for overall emissions limits.

2024-2029 Emissions Limits – §28-320.3.1.1 Local Law 97

Emissions limits for Greenhouse gas coefficient of energy consumption for calendar years 2024 through 2029. The annual building emissions of a covered building in accordance with this section, greenhouse gas emissions shall be calculated as follows for calendar years 2024 through 2029:  


    1. Utility electricity consumed on the premises of a covered building that is delivered to the building via the electric grid shall be calculated as generating 0.000288962 tCO2e per kilowatt hour, provided, however, that the department, in consultation with the office of long term planning and sustainability, shall promulgate rules governing the calculation of greenhouse gas emissions for campus-style electric systems that share on-site generation but make use of the utility distribution system and for buildings that are not connected to the utility distribution system.  

    1. Natural gas combusted on the premises of a covered building shall be calculated as generating 0.00005311 tCO2e per kbtu.  

    1. #2 fuel oil combusted on the premises of a covered building shall be calculated as generating 0.00007421 tCO2e per kbtu.  

    1. #4 fuel oil combusted on the premises of a covered building shall be calculated as generating 0.00007529  tCO2e per kbtu.  

    1. District steam consumed on the premises of a covered building shall be calculated as generating 0.00004493tCO2e per kbtu.

When Does Local Law 97 Begin?

Local Law 97 limits come into effect in 2024. The 2024 standards were designed to cover only the 20-

25% highest carbon-emitting buildings. About 75-80% of multifamily buildings are already in compliance with 2024. 

The 2030 requirements are more stringent, so compliant building owners today should begin to think about the strategies they want to implement in the coming years. Partnering with a building energy specialist early and establishing a plan for the next decade is a good step to ensure that the transition to future compliance is seamless. 

What Commercial Buildings Does Local Law 97 Effect?

Any commercial building over 25,000 square feet (or any commercial compound under single ownership over 50,000 square feet) must comply with Local Law 97. The Law provides a number of exceptions, which include up to three-story buildings in which multiple dwellings are independently owned and operated; city buildings; New York City Housing Development properties; rent-regulated accommodations; buildings owned by religious institutions and used exclusively for public worship; and buildings owned by housing development fund companies organized through the Business Corporation Law and Article 11 of the Private Housing Finance Law.

Depending on the type of commercial property, emissions standards differ. To learn more, see the New York Engineers chart identified below.

Does a building have to change in order to comply with this law?

For 2024, it depends. If your covered building is currently not in compliance with 2024 limits, you will need to modify your building this year in order to avoid paying steep fines next year.

By 2030, many more New York City buildings will be out of compliance, so building owners should perform assessments now in order to develop compliance strategies, implement them, and begin seeing the benefits of owning and operating a low-energy building as soon as possible.

What Are the Fines if I Do Not Comply with Local Law 97

Local Law 97 provides a formula for determining the magnitude of the fine for non-compliance: the difference between the emissions limit for a given year and the reported building emissions for that year, multiplied by $268. 

This means that, for the most part, penalties for non-compliance vary relative to building performance, not building size. Even if a building owner can’t get all the way to the emissions limit in a year, the penalty can be lessened by taking steps to lower building emissions. 

Are There Any Incentives with Local Law 97?

Because compliance with Local Law 97 is mandatory, there are no incentives specifically for compliance. But don’t fear! Both utility companies and New York State offer incentive programs for owners seeking to reach compliance.

The New York State Energy Research and Development Authority (NYSERDA) offers programs such as the NYS Clean Heat Program, which provides rebates and financing options for switching to heat pump technologies. NYSERDA has a host of programs targeting specific building types and improvement strategies, and are adding new programs all the time.

Multifamily buildings in Brooklyn and Queens can participate in ConEdison’s Multifamily Buildings Neighborhood Programs, which provide incentives up to 100% of total measurable costs. The New York City Energy Efficiency Corporation provides loans of $200,000 or more to pay for up to 90% of proposed clean-energy products. Inclusive Prosperity Capital offers 20-year loans to fund 100% of energy upgrades from $50,000 to $2 million.

Finally, Property Assessed Clean Energy financing allows business owners to finance upgrades through a property tax assessment.

Learn more about programs available to help finance energy upgrades here.

Benefits of Building Energy Efficiently

Other than compliance with Local Law 97, energy-efficient buildings provide immense benefits to occupants and property owners alike:

Reduced Energy Consumption:

By incorporating more energy-conscious features like high-performance insulation, airtight barriers, and advanced windows, energy usage can be minimized, which contributes to lower heating and cooling requirements. This reduction in energy consumption leads to decreased utility bills for occupants and property owners.

Improved Indoor Comfort:

Featuring excellent insulation and airtight construction, energy-efficient buildings prevent drafts and excessive heat loss. This helps maintain a more consistent and comfortable indoor temperature, reducing the need for excessive heating or cooling. Additionally, advanced ventilation systems in energy-efficient buildings ensure a constant supply of fresh air, improving indoor air quality.

Health Benefits:

Energy-efficient buildings often prioritize indoor air quality, which has a direct impact on occupants’ health. With efficient ventilation systems, pollutants and allergens are effectively filtered out, reducing the risk of respiratory issues and allergies.

Environmental Sustainability:

Thanks to new laws like Local Law 97, compliant buildings play a crucial role in reducing greenhouse gas emissions and combating climate change. By utilizing less energy for heating, cooling, and lighting, these buildings help lower carbon footprints. Additionally, the integration of renewable energy systems, such as solar panels, further enhances their sustainability and contributes to a cleaner environment.

Long-Term Cost Savings:

While energy-efficient building upgrades or new builds have higher upfront costs due to advanced construction techniques and energy-efficient materials, they offer long-term cost savings. Lower energy consumption translates into reduced utility expenses over time.

How Can I Reduce Carbon Emissions?

There are many ways to reduce carbon emissions, from component replacement to increasing insulation and removing thermal bridges to investing in on-site renewable energy.

For the first round of Local Law 97 limits, most non-compliant buildings can meet the applicable emissions limits through component replacement and on-site renewables. For 2030 and beyond, building owners will likely have to invest more heavily into comprehensive approaches to sustainable design, such as the replacement of mechanical systems, improved envelope strategies, and switching to all-electric mechanicals and appliances. Non-compliant owners should keep this in mind when deciding what strategies to adopt this year, to prevent having to re-do performance measures in the future.

Source 2050 is Your Resource for Eco-Friendly Supplies

Whether you are looking to improve your envelope airtightness, upgrade your mechanicals, or install renewable energy sources, Source 2050 is your partner for specifying and sourcing these solutions.

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Your Guide to NYC Local Law 97 for Sustainable Building 24

Airtight Building Materials

Window Replacement or Improvement 

With a broad selection of high-performance windows and treatments to improve existing windows, Source 2050 will make replacing or upgrading your windows easy and hassle-free.

See some of our Source2050 High Performance solutions. 

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High-Performance Insulation

Poorly insulated walls and roofs let your conditioned air escape and outside air creep in, drastically increasing the load placed on your conditioning systems. With blown-in, batt, and rigid options, including the latest in natural and recycled materials products, Source 2050 will let you find the right insulation solution for your building. Search by product type, r-value, fire rating, and more.

See some of our Source2050 High Performance solutions.

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Thermal Breaks 

Even when your envelope is airtight, outside temperatures can still penetrate your building through thermal bridges. Stop your mechanical systems from working overtime to combat these incursions by installing thermal break materials around windows, doors, and anywhere else conducting materials are exposed to the elements.

See some of our Source2050 High Performance solutions.

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Heat Pumps 

Heat pumps are essential for your house due to their ability to provide efficient heating and cooling solutions. Even if your home is well-insulated and airtight, external temperatures can still impact its thermal comfort through thermal bridges. By installing a heat pump, you can prevent your HVAC system from overworking to counteract these temperature infiltrations. Heat pumps act as thermal breaks, minimizing the impact of conducting materials exposed to the elements, such as windows and doors. They effectively regulate the indoor temperature, ensuring optimal comfort while reducing energy consumption. With a heat pump, you can maintain a consistent and pleasant indoor environment while maximizing energy efficiency.

See some of our Source2050 High Performance solutions.

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Indoor air quality is a crucial aspect of any building, and maintaining a healthy and comfortable environment is essential. Even with a well-sealed envelope, external pollutants and stale air can still find their way into your living or working space through thermal bridges. To prevent your mechanical systems from overworking to combat these infiltrations, consider installing an Energy Recovery Ventilator (ERV). ERVs act as thermal breaks by effectively exchanging stale indoor air with fresh outdoor air while minimizing the transfer of heat or cold. By strategically placing ERVs around windows, doors, and other areas where conducting materials are exposed to the elements, you can ensure a constant supply of fresh air, improve indoor air quality, and optimize energy efficiency. ERVs are a valuable addition to your building, helping you maintain a healthier and more comfortable living or working environment.

See some of our Source2050 High Performance solutions. 

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Heat Recovery Systems

To prevent unnecessary strain on your mechanical systems and maintain energy efficiency, it’s crucial to address thermal bridges in your building. These bridges allow outside temperatures to infiltrate, compromising indoor comfort. One effective solution is to install a heat recovery system. By implementing heat recovery materials around windows, doors, and any areas where conducting materials are exposed to the elements, you can minimize heat transfer and optimize energy usage. Heat recovery systems work by capturing and reusing the heat from outgoing air to preheat incoming fresh air, reducing the workload on your HVAC system. This not only helps maintain a comfortable indoor environment but also improves energy efficiency by preventing unnecessary heating or cooling. Invest in a heat recovery system to ensure a well-regulated and energy-efficient building that promotes both comfort and sustainability.

See some of our Source2050 High Performance solutions.

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Radiant Heating and Cooling

Even with a well-sealed envelope, outside temperatures can still seep in through these bridges, causing your mechanical systems to work harder to maintain comfort. To combat this, consider implementing a radiant heating and cooling system. By installing thermal break materials around windows, doors, and any areas where conducting materials are exposed to the elements, you can minimize the impact of thermal bridges. Radiant heating and cooling systems utilize the transfer of thermal energy through surfaces, such as floors, walls, or ceilings, to efficiently heat or cool a space. This method allows for precise temperature control, ensuring a comfortable environment while reducing energy consumption. With a radiant heating and cooling system in place, your mechanical systems can operate more efficiently, resulting in improved comfort and energy savings. See some of our Source2050 High Performance solutions. 

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Building Types and Emission Limits Covered by Local Law 97

Updated LL97 Property Types (A – L) and Emission Limits (tCO2-eq per sq.ft.)

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Updated LL97 Property Types (M – O) and Emission Limits (tCO2-eq per sq.ft.)

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Updated LL97 Property Types (P – Z) and Emission Limits (tCO2-eq per sq.ft.)

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Graphics courtesy of New York Engineers.