Question one: who owns the roof
In most Massachusetts condominium regimes the roof is a common element controlled by the association, even where a unit has exclusive use of a deck or terrace beneath it. That is usually good news, because it means the association can act. But it has to act according to its own documents.
Before we quote, we ask to review three things:
- The master deed and declaration of trust, to confirm the roof is a common element and to identify any restriction on altering common elements.
- The bylaws, to establish the voting threshold. Some associations can approve a capital improvement by board vote; others require a supermajority of unit owners, and a few require unanimous consent for structural alterations.
- The reserve study and current budget, because how the project is paid for changes which approval you need.
Getting this wrong is the most common reason a condominium solar project dies after six months of work. A board that approves a system it did not have the authority to approve creates exposure for itself and gives any dissenting owner a reason to litigate.
Question two: which meter does the system feed
This is the technical fork in the road, and it determines the entire economic case.
| Configuration | What solar can offset | Who benefits |
|---|---|---|
| House meter, common areas only | Corridor and garage lighting, elevators, common HVAC, pumps, laundry, EV chargers, amenity spaces | The association, through a lower common expense |
| Master-metered building | The entire building load, including units | The association, and unit owners through their assessments |
| Individually metered units, no master | Nothing directly. Requires allocation of net metering credits to participating accounts | Whichever accounts are designated to receive credits |
The third case is where most condominium projects in Massachusetts actually sit, and it is where credit allocation matters. Massachusetts net metering allows the credits generated by a facility to be allocated to other utility accounts in the same service territory and load zone. That mechanism is what lets a roof-mounted array serve individually metered units, but the allocation has to be set up correctly with the utility and revisited as units change hands.
The credit value nuance most proposals skip. Under Massachusetts rules, new solar Class II and Class III facilities are generally credited on the basis of 60 percent of net excess generation. Facilities that are cap exempt because they serve on-site load receive 100 percent. For an association, that pushes the design toward sizing the array against real common-area or master-metered consumption rather than filling the roof and exporting the difference.