Follow up materials relative to the Green Roofs Zoning Petition

Included is a list of developments currently under review, but without a filed special permit or building permit (in cases where a special permit is not required), which would be affected if the petition were adopted. Information on green roof requirements in other cities. Per Policy Order #9 of April 12, 2021, report on the impact of eliminating parking decks from the list of rooftop areas not considered “available” per the Petition. Per policy order #10 of April 12, 2021, amendment to exempt affordable housing.

Determination of appropriate mitigation costs. Careful review of the proposed zoning text, in the version recommended by the Ordinance Committee, to identify technical issues that may be problematic when applying the proposed language and to suggest alternative language where appropriate. Narrative responses are included on the following pages, and an annotated markup version of the zoning text is attached.

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Effective Date

Typically, when an amendment to the Zoning Ordinance is adopted, it would affect any development that has not yet been issued a special permit, or a building permit if a special permit is not required, by the date of first advertisement of the zoning petition – in this case, ca. January 21, 2021. The following is a list of projects that had not yet been issued a permit by that date, including developments that have submitted an application or have begun a community engagement process.

Language to include an effective date is included in the attached zoning text. The list includes Affordable Housing Overlay (AHO) Projects that have begun their community review process; however, because AHO Projects do not require a special permit, they would not be “protected” from zoning amendments until they receive a building permit. The list includes projects involving a total of 25,000 square feet or more, including new buildings and alterations/additions.

As discussed further below, it is unclear from the current zoning petition language if alterations/additions would be subject to the requirements or not.

Project Location/Name

Status Project Type / Approx. Size Use

CambridgeSide PUD

Special permit issued 2/17/2021

New buildings +

alterations (1,665,000 SF) Use 51 Vassar St Approved, special permit not filed (174,000 SF) Academic 269-301 Vassar St (MIT Grad Housing) (327,000 SF) Academic / Dormitory 2072 Massachusetts Ave BZA Review (Comp. Permit)

New building (57,395 SF)

727 Massachusetts Ave

Addition + alteration

(41,895 SF) Hotel 600-624 Main St (Ragon Institute) (185,810 SF) Laboratory 600 Massachusetts Ave

Addition (79,203 SF)

Residential + Retail

MIT Volpe PUD

(2,820,000 SF) Use + Cmty Ctr. 585 Third St (Constellation Site) Pre-application (PUD special permit) (525,000 SF)

Commercial Lab +

Arts Center

Metropolitan Warehouse -

MIT Architecture Dept

Pre-application (building

permit)

Alteration (1,155,468 SF)

Academic

Alewife Park / Jerry’s Pond

Pre-application (special permit)

New buildings +

alterations (735,494 SF) Multi-Site Commercial

MXD amendment

(Eversource Substation) Pre-application (special permit) (1,200,000 SF)

Use + Utility

52 New St (Just-A-Start) (150,000 SF) 278 Rindge Ave (Jefferson Federal) (379,925 SF) 102 Sherman St (Walden Square Apts.) (145,323 SF)

Tobin School

Community Process (City

meetings) (TBD)

City School

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Green Roofs in Other Cities

Many cities have adopted policies that incentivize or mandate green roofs but have taken a variety of regulatory approaches. A few key examples of cities noted by the Council that have prescriptive green roof requirements are discussed here. Other cities known for their leadership in green roofs, such as Chicago and Washington, D.C., rely on incentives and other programs rather than prescriptive requirements.

Denver, CO

Denver passed a green roofs ordinance in 2017 that required new buildings over 25,000 square feet to install a green roof and existing buildings over 25,000 square feet to install a green roof when the roof is replaced. However, implementation of the ordinance revealed several limitations, including conflicts with the building code and state water regulations, an inequitable burden of compliance on different building types and uses, and high construction costs.

In response, the city formed a green roofs review task force that worked with a consultant to evaluate whether alternatives to green roofs would provide the same function. As a result, Denver passed a new ordinance in 2018 that now requires buildings over 25,000 square feet to meet a cool roof requirement and one of five options, as shown in the image below.

Image 1: Options for Green Building compliance in Denver (source: https://crej.com/news/program-offers-options- for-green-building-compliance/) Staff at the City and County of Denver report that the most common measure that is pursued is the energy program, which allows several different options. Some development projects have installed ground-level vegetation, but there have only been a couple of green roof installations.

Denver has also not seen much utilization of the payment in lieu of installation option because the fee is high enough to discourage its usage. It is also important to note that the ordinance defines “available roof area” separately from the full extent of the roof area and offers two ways of calculating area, allowing the applicant to choose the lesser of the two.

In addition, Denver does not have a green building requirement for new development of this scale like Cambridge does in Article 22.000 of the Zoning Ordinance.

Page 4 of 10 Portland, OR Portland has an “ecoroofs” requirement, which is mandated for all new buildings in the “central city” area with a net building area of at least 20,000 square feet. Ecoroofs must cover all parts of the building’s roof area that are not exempted. The exempted areas include roof top parking, roof area with a slope greater than 25%, and other rooftop systems including mechanical equipment, photovoltaic arrays, and stairwell enclosures, up to 40% of the roof area. The City also offers a Gross Floor Area (GFA) bonus for development projects in mixed-use zones outside of the central city that install green roofs or solar roofs. The ecoroofs requirement was outlined in the Portland Central City 2035 Plan (CC2035 Plan) and went into effect July 2018.

Toronto, Ontario, Canada

Toronto was the first city in North America to require green roofs on new development. The Green Roof Bylaw sets a graduated requirement for new developments that are over 2,000 square meters (approximately 21,500 square feet). As shown below, depending on the size of the building, between 20-60% of the available roof area for commercial, institutional, and residential development must meet the green roof standard. Gross Floor Area of Building

Coverage of Available

Roof Space