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Tale of Two Cities: NYC's LL97 and Boston's BERDO

Updated: Jan 21, 2022


There's a new building ordinance in town for the Northeast region. Boston recently passed a revamped version of the Building Energy Reporting and Disclosure Ordinance (BERDO that requires large buildings to reach zero emissions by 2050. Like New York City's infamous Local Law 97, the new BERDO requires buildings to comply with carbon emission limits or face high penalties.


How do the New York City and Boston building ordinances compare? There are key differences in each policy that property owners should know.


Buildings Targeted

New York City requires that all buildings 25,000 square feet or more comply with LL97 starting in 2024. The mandate affects about 60% of the NYC building floor area, contributing approximately 70% of the city's emissions.


Boston's BERDO 2.0 will cover residential and non-residential buildings 20,000 square feet or larger. Buildings between 20,000 and 35,000 square feet or residential buildings with 15 to 35 units will need to begin reporting their energy use in 2022, but will not have to comply with the emissions standards until 2031. However, buildings 35,000 square feet or high will have to comply starting in 2025. The ordinance covers approximately 4% of buildings, contributing 60% of Boson's emissions from buildings.


Carbon Limits

Another notable difference is that the carbon limits for BERDO are measured in kg CO2e per square foot per year, whereas LL97's metric is in tons of CO2e per square foot per year. This subtle difference is something to pay attention to when comparing the carbon reporting of buildings. Boston has established carbon limit compliance periods until 2050, while NYC has only defined caps through 2034.


The following is a breakdown of the LL97 and BERDO carbon limits, both in kgCO2e, for the first compliance periods since New York has not defined the later limits. Boston's property types are categorized on building type, and NYC is by use and occupancy classification shown in parathesis.