Title 5 Building Reviews (Form C & Form S)

Why is a Title 5 Review Required?septic
Massachusetts Title 5 regulations (310 CMR 15.000) were established in 1995 to protect homeowners and the environment by ensuring septic systems are properly designed, used, and maintained. When you renovate or add space to your home—such as finishing a basement, building an addition, or altering room use—your property's wastewater flow may increase. A Title 5 Building Review helps determine if your current system can support those changes before construction begins. This helps prevent costly system failures and ensures compliance with local and state health codes.

  • Please review the Health Division's Form C Policy before applying.

Room Count Matters – Not Just Bedrooms
For septic-connected properties, Title 5 evaluates system capacity based on the total number of rooms in the home—not just bedrooms or bathrooms. This includes any room that could reasonably be used as sleeping space, such as offices, dens, finished attics, or basements. For example, even if a home has 3 bedrooms, if there are 9 total rooms, the septic system may be evaluated for the higher room count. Room count affects the property's design flow, which must not exceed the approved capacity of the system.

Note: Room count is also considered for sewer-connected properties. Projects that increase wastewater flow may be subject to a Sewer Improvement Fee (SIF).

Accessory Dwelling Unit (ADU) Guidance
In April 2025, the Massachusetts Department of Environmental Protection (MassDEP) issued updated guidance on Accessory Dwelling Units (ADUs). The document outlines how ADUs may impact septic system reviews and when additional Title 5 evaluations are needed:

When is a Review Required?
A Title 5 Building Review is required before applying for a building permit for any renovations, additions, or finishing of rooms that could impact wastewater flow or affect the septic or sewer connection.

What Do I Need to Submit?

  • Form C for septic-connected properties
  • Form S for sewer-connected properties
  • A detailed description of the proposed work
  • Existing and proposed floor plans of the entire building

A building permit cannot be issued until the Health Division has completed the Title 5 Building Review.

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