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ADU Zoning in Blackstone, MA

Yes, you can build an ADU in Blackstone — ADUs are approved by right under the Affordable Homes Act.

Complete ADU zoning guide for Blackstone, Massachusetts. Learn about allowed ADU types, approval process, size limits, and local zoning regulations.

Data verified as of March 2, 2026
State Baseline Only — Local Details Not Yet Researched

ADU Regulations in Blackstone

Blackstone follows the Massachusetts state baseline under the Affordable Homes Act. This means all Massachusetts state-level ADU rights apply — including by-right approval, no owner occupancy requirement, and standardized size limits. Blackstone may also have additional local regulations that supplement the state baseline.

By-Right Approval: No Hearing Required

ADUs in Blackstone are approved by right. This means you submit your building plans to the building department and receive a building permit without going through a public hearing or special permit process. By-right approval significantly reduces both the timeline and cost of your ADU project.

Allowed ADU Types

Blackstone allows the following ADU types: detached, attached, conversion.

  • Detached — standalone structure in your yard, offering maximum privacy and design flexibility
  • Attached — shares a wall with your existing home, reducing construction costs and utility connections
  • Conversion — transforms existing space (basement, attic, or garage) into a separate dwelling unit

No Owner Occupancy Required

Blackstone does not require owner occupancy for ADUs, a right guaranteed by the Affordable Homes Act. This means you can rent both your main home and the ADU, making it a viable pure investment property. You're also free to live in the ADU and rent the main house.

Historic District Considerations

Blackstone has historically significant areas including Blackstone Heritage Corridor, Blackstone Manufacturing Company Historic District. If your property is located within or adjacent to a historic district, your ADU design may need to go through additional design review to ensure compatibility with the neighborhood's architectural character. This can affect exterior materials, rooflines, and window styles. Consult with the local historical commission early in your planning process.

Conservation and Wetlands

Blackstone has conservation areas including Blackstone Gorge, Blackstone Park Conservation District, Blackstone River and Canal Heritage State Park. If your property is near a wetland, river, or conservation area, you may need approval from the Conservation Commission before building an ADU. Massachusetts requires a buffer zone (typically 100 feet) around wetlands, and construction within this area requires a Notice of Intent filing.

Important: State Baseline Data

The information on this page reflects Massachusetts state baseline rules. Blackstone may have additional local requirements. We recommend confirming with your local building department before starting your project.

Blackstone ADU Rules at a Glance

Max Size

900 sq ft

% of Home

50%

Parking

1 space(s)

Approval

BY RIGHT

Owner Occupancy

Not required

Rental Allowed

Yes

Short-Term Rental

Not allowed

Blackstone Building Department

Blackstone Town Hall

15 St Paul St, Blackstone, MA 01504, USA

Phone: (508) 883-1500

Visit Website →

Frequently Asked Questions

Are ADUs allowed by right in Blackstone, MA?

Yes. ADUs in Blackstone are approved by right — you submit your plans to the building department and receive a building permit without a public hearing or special permit process. This is guaranteed by the Affordable Homes Act.

What types of ADUs can I build in Blackstone?

Blackstone allows detached, attached, conversion ADUs. With up to 900 sq ft allowed, a detached ADU gives you the most flexibility for a full living space.

Do I need to live on the property to build an ADU in Blackstone?

No. Blackstone does not require owner occupancy — this is a right guaranteed by the Affordable Homes Act. You can rent both your main home and the ADU, making this a pure investment property if you choose.

How big can I build an ADU in Blackstone, MA?

In Blackstone, you can build an ADU up to 900 square feet or 50% of your home's living area, whichever is larger. With 900 sq ft, you have enough room for a full 2-bedroom cottage with a kitchen, bathroom, and living area. This is guaranteed by the Affordable Homes Act.

Does Blackstone have historic district rules for ADUs?

Yes. Blackstone has historically significant areas including Blackstone Heritage Corridor, Blackstone Manufacturing Company Historic District. If your property is in or near a historic district, your ADU design may require review by the local historical commission for architectural compatibility. This can affect timelines and design choices.

Can I rent out my ADU in Blackstone?

Yes, long-term rentals are allowed for ADUs in Blackstone. However, short-term rentals (like Airbnb) are not currently allowed for ADUs.

How accurate is the ADU data for Blackstone?

The information on this page reflects Massachusetts state baseline rules under the Affordable Homes Act. Blackstone may have additional local requirements that differ from the state baseline. We recommend confirming with your local building department before starting your project.

Check Your Address

See exactly what ADU rules apply to your specific property in Blackstone.