In Boston, whether you need a permit for major plumbing repairs depends on the scope of the work you intend to carry out. Generally, significant plumbing work, such as installations, replacements, or alterations of plumbing systems, typically requires a permit. This is to ensure that all work complies with local building codes and safety regulations.

According to the Boston Inspectional Services Department, any plumbing work that involves:

• Installation of new plumbing systems
• Replacement of existing plumbing fixtures (e.g., sinks, toilets, water heaters)
• Alterations to existing plumbing systems (e.g., moving pipes, adding new lines)
• Repairs that may affect the plumbing system's integrity

will typically require a permit. For instance, if you are replacing an old water heater with a new one, you will need to obtain a permit. This is not only to ensure compliance with safety standards but also to verify that the work is performed by a licensed plumber.

However, minor repairs, such as fixing a leaky faucet or unclogging a drain, generally do not require a permit. It is always best to consult with a licensed plumber or contact the Inspectional Services Department directly to clarify whether your specific project requires a permit.

To obtain a plumbing permit in Boston, you would usually need to:

1. Complete a plumbing permit application.
2. Provide detailed plans or specifications of the work to be performed.
3. Pay the associated permit fees.
4. Schedule an inspection upon completion of the work.

For more information on the specific requirements and to access the plumbing permit application, you can visit the Boston Plumbing Permits page.

In summary, if you are planning major plumbing repairs in Boston, it is crucial to check the regulations and obtain the necessary permits to ensure your project is compliant and safe.