The solar ordinance requires that new construction and substantial rehabilitation projects of over 10,000 square feet or projects with 10 or more residential units include a solar energy system. The size of this system must be equivalent to at least 50% off the roof area of all buildings or, in the case of uncovered parking structures, at least 90% of its top level.
Solar Energy System Assessment:
Projects within this scope are required to submit a solar assessment that must, at minimum, include an analysis of possible solar systems for the site and the maximum areas where rooftop or ground-mounted solar systems are feasible. An initial solar assessment should be submitted with the application for site plan review and a final solar installation plan must be approved by the Director of Planning, Development, and Sustainability (acting in their role as the Energy & Environment Director) before a building permit can be issued.
Exemptions:
Building projects are not required to install a solar system if there is not a suitable space for solar. Specifically, projects are exempt if there is no solar-ready zone available, if the solar-ready zone is shaded for more than 50 percent of yearly daylight hours, or for building conversions with insufficient structural load capacity. The solar-ready zone area is defined as 50 percent of the roof area that is either flat or oriented between 110 degrees and 270 degrees of true north and does not include any roof area required for safety or emergencies by the MA fire code. These exemptions exist to ensure that all required solar systems are efficient, productive, and safe for the community.