Acting Mayor Kim Janey signed an ordinance Tuesday intended to address climate change by requiring large buildings in Boston to achieve net-zero carbon emissions by 2050.
The measure “is a monumental achievement that will have positive impacts on our residents for generations to come,” Janey said in a statement. “We know that the negative effects of climate change bear a disproportionate burden on our most socially vulnerable communities.’’
The City Council unanimously approved the ordinance last month.
It applies to about 3,500 commercial and residential buildings of 20,000 square feet or more, or about 4 percent of structures in the city, according to city officials. They account for 60 percent of Boston’s building emissions.
To reach the goals set out in the ordinance, building owners can perform energy-efficiency improvements; switch to clean, efficient electric heating systems or fossil fuel-free systems; and purchase clean energy.
“By passing and signing this transformative climate legislation into law, we are codifying equity and resilience in our city’s large buildings,” said City Councilor Matt O’Malley, the sponsor of the measure.
The ordinance was modeled on similar measures in New York, St. Louis, and Washington, city officials said. Developers and building owners were included in the process.
The measure signed Tuesday is an amendment to a 2013 ordinance that required that all commercial and residential buildings of at least 35,000 square feet or that have 35 units or more to report their energy and water use to the city every year.
Buildings covered were also required to show concerted efforts to reduce their energy use or emissions every five years through energy actions or audits.
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