Green roof updates

October 2021

essential reads

Last spring, the New York City Council passed an ambitious climate legislation package focused on buildings, which are responsible for almost three-quarters of all local emissions. 

GRRA members Dustin R. Partridge and Danielle Spiegel-Feld sit down with Urban Omnibus to clarify what New York’s new climate laws can mean for city residents, building owners, and birds.

New in Financing green roofs

The Nature Conservancy has developed a map to help New Yorkers find the NYC Green Roof Tax Abatement rate in their Community District! ⁠

A New York City property tax abatement is available for property owners who install a green roof on their buildings. The current program runs through June 30, 2024, and offers $5.23 per square foot of green roof installed in most parts of the City and $15 per square foot in Priority Community Districts.⁠


Featured site

The seven-acre sedum green roof is the largest green roof in NYC. It absorbs up to seven million gallons of stormwater run-off annually and has reduced the facility's annual energy consumption by 26 percent. Used by 29 bird and five bat species and home to thousands of honeybees, the green roof has become a sanctuary for wildlife on Manhattan's West Side. View the Javits Center Sustainability Report.

New in Research

Rebuild by Design asked 20 experts, including #GRRA members Timon McPhearson and Danielle Spiegel-Feld to offer "Concrete ideas of policies and projects that protect our communities from the flash flooding and loss of life which we experienced from Hurricane Ida."


Green Roof Common Questions

What is a green roof?

Green roofs provide numerous social, economic, and environmental benefits for individuals, communities, and cities. A green roof is a layer of vegetation installed above a system of barriers and membranes that protect and insulate the structure. There are two types of green roofs. Extensive Roof

  • Shallow growing medium (soil) between 2 and 6 inches
  • Less structural support
  • Limited diversity of plants with less intricate root systems
  • Less investment and little maintenance once established
  • Requires minimal maintenance after the first year of establishment
  • For roofs without occupancy or capacity for gathering
Intensive Roof
  • 6+ inches of growing medium (soil)
  • Greater weight-bearing capacity to support a deeper growing medium and heavier plants
  • It can support a wider variety of plants and trees
  • Can support raised beds
  • Higher initial investment and more intensive maintenance
  • May require an irrigation system
  • It may be accessible for residents to socialize, with appropriate access and a Certificate of Occupancy.

Where are green roofs located in NYC?

As of 2016, there were 60 acres of green roofs in all five boroughs of NYC. Green roofs are found on residential, commercial, city, state, and institutional buildings, including universities and major facilities like the Jacob K. Javits Convention Center. While this may sound like a lot, green roofs account for less than a tenth of a percent of the city’s roughly one million rooftops, which add up to about 40,000 acres of underutilized space.

Are green roofs important to urban environments?

Green roofs can provide many benefits for the inhabitants of NYC, including stormwater management, heat island mitigation, thermal regulation habitat enhancement, and recreational opportunities. Learn more about environmental benefits.

How much does a green roof cost and are there financing options?

Before installing a green roof, consider the initial construction investment, maintenance cost, return on investment, and financing options, including grants and tax incentives provided by NYC and other entities.

Learn more about financing green roofs

Can I design and install a green roof myself?

When designing a green roof, it is crucial to consider the environment, intent, and building requirements. The information on this website can help you get started, but it is not intended to be a comprehensive design guide. It is strongly advised to hire a professional design-build consultant to guide you through the design process, assist with procuring funding and permits, and safely install and maintain your green roof!
Learn more about designing green roofs.


Benefits of Green Roofs


Improves Air Quality

Green roof technology can cut carbon and reduce air pollutants such as nitrous oxide, sulfur dioxide, and ozone. In addition, green roofs remove harmful fine particulate matter in the surrounding air.

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Extends Roof Longevity

By protecting roof structures from weathering and degradation, green roofs decrease the cost of repairs and maintenance. Green roofs last up to twice as long as conventional roofs.

Green Roofs

Increases Property Value & Decreases Tennant Turnover

Residential and commercial properties with green roofs have higher property values, lower tenant turnover, and lower energy costs. These advantages mitigate the initial high cost of green roof installation.


Increases Energy Efficienciency

Because of their insulating effect, green roofs can increase energy efficiency by reducing energy costs year-round and prolong the life of heating, ventilation, and HVAC systems. Calculate green roof energy savings here and learn how to make your building more energy-efficient.

Friends Relaxing on Grass

By providing outdoor space where people can socialize, garden, play, and relax, green roofs, like parks, may improve overall health and well-being. Green roofs are an important source of green space in dense cities. In addition, research has found that office workers are 2.9% more productive when the view out of their office windows includes vegetation.


Lowers Urban Temperatures

Green roofs can insulate buildings, making them cooler in summer and warmer in winter. An increase of green area decreases ambient air temperature and helps mitigate the urban heat island effect.


Retains Stormwater

Green roofs can retain more than half of annual precipitation, with performance dependent on the local microclimate, precipitation characteristics, growing media depth, and vegetation type. Stormwater retained by green roofs reduces the volume of runoff discharged to separate or combined sewer systems, helping to keep our waterways clean.

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Provides Needed Habitat and Increases Urban Biodiversity

Amid urban infrastructure, green roofs provide much-needed habitats on otherwise unutilized space. They act as connectors for many species, including birds, bees, bats, and insects, to move from one urban green space to another.


Reduces Noise &

Increases Insulation

Green roofs can reduce internal and external sounds by nearly 40 decibels. The soil substrate and plants absorb sound, unlike a conventional roof that simply reflects it.

With support from the Natural Resources Defense Council, and in partnership with the Mayor’s Office of Sustainability and the NYC Retrofit Accelerator, the Building Energy Exchange is holding a series of programs designed to demystify the components of the Climate Mobilization Act and connect our community with relevant solutions. Hear from experts directly involved in the development of the legislation and those charged with its implementation to understand how NYC’s Climate Mobilization Act will impact your real estate portfolio. Most importantly, learn about resources available through NYC Retrofit Accelerator and Building Energy Exchange to help your building comply with these new requirements.

green roof events