Which permits does a generator need?
| Permit | Who pulls it | What it covers |
|---|---|---|
| Electrical | Licensed electrician | The generator, transfer switch and wiring under the Massachusetts Electrical Code (527 CMR 12, the 2023 NEC) |
| Gas | Licensed gas fitter or plumber | The gas line from the meter or tank, under 248 CMR 3.00 |
| Propane tank | Filed with the local fire department | Tank location and installation, under the fire code (527 CMR 1.00) |
| Zoning or building | Filed with the town, where required | Placement, setbacks and noise |
What does the electrical permit cover?
In Massachusetts, electrical work needs a licensed electrician, and the generator and transfer switch are electrical work. The Massachusetts Electrical Code is the 2023 National Electrical Code with state amendments. It sets how the transfer switch connects and how the generator is sized, and the town's wiring inspector checks the work before it is covered up.
What does the gas permit cover?
The gas line from the meter or propane tank to the generator is gas fitting work, permitted under 248 CMR 3.00 and done by a licensed gas fitter or plumber. Products used on gas in Massachusetts also go through state product acceptance. Kohler, for example, states that its 26RCA is accepted by the Massachusetts Board of Registration of Plumbers and Gas Fitters.
What about a propane tank?
The local fire department permits propane storage under the state fire code. Towns ask for a drawing that shows the tank's distance to the property lines, the house, doors, windows and anything that could ignite. Wellesley, for one, says the tank should not be filled until the permit is granted and the fire department has inspected it. See natural gas or propane for the rest.
How far from the house does a generator sit?
Manufacturers follow NFPA 37. Generac lists its Guardian units for installation as close as 18 inches to the house, and requires 5 feet from windows, doors and vents, 5 feet clear above, and 3 feet at the front and ends, including from shrubs. Kohler's 26RCA meets the NFPA guideline of 18 inches from combustible materials. Both say local codes come first.
Massachusetts has no single statewide setback for generators. Towns apply their own zoning, setback and noise rules, and some need special permit relief for a generator in a front or side yard. We check your town's rules before we choose the spot.
What about New Hampshire and Rhode Island?
In New Hampshire, towns such as Concord and Chester require state-licensed electricians and gas fitters and their own generator or mechanical permits. In Rhode Island and every other town, we confirm the local requirements for each job before we quote.
