Article 22 Green Roofs Requirement
Overview
Under the Green Roofs Requirement, most new buildings or structures over 25,000 square feet must have a green roof and/or solar energy system. (See Section 22.30 of the Zoning Ordinance). These systems are not included in the Gross Floor Area.
Developers can apply for a special permit from the Planning Board to reduce the amount of green roof they are required to build. The project team must make a “unit contribution” to the Cambridge Affordable Housing Trust for every square foot of reduction that the Planning Board grants.
Calculating a Cash Contribution
- Identify Total Roof Area
- Identify Exempt Roof Area:
- Areas with a slope greater than 25%;
- Areas that are usable by building occupants or the general public;
- Vehicular parking decks; and
- Mechanical equipment and appurtenances carried above the roof and not intended for human occupancy.
- Calculate the Required Green Roof Area
- Required Green Roof Area = 80% * (Total Roof Area from Item 1 - Roof Area Exempt from Item 2)
- Identify Built Green Roof Area in the project
- Calculate the Required Green Roof Area Not Installed
- Required Green Roof Area Not Installed = Required Green Roof Area from Item 3 – Built Green Roof Area from Item 4
The amount of the cash contribution is finally calculated by multiplying the Required Green Roof Area Not Installed by the “Unit Price Contribution” according to the below chart:
Calendar Year
|
Unit Price Contribution
(Per Square Foot of Required Green Roof Area Not Installed)
|
2022 (and before)
|
$37.35
|
2023
|
$39.12
|
2024
|
$40.90
|
Note: Figures subject to recalculation every three (3) years. Cash contributions shall be calculated and provided at the time of issuance of a building permit for a project.
For more information or to make a payment
Please discuss your project with CDD staff by contacting
Swaathi Joseph, Zoning Project Planner
sjoseph@cambridgema.gov
617/349-4668