Semi-attached homes are extremely common across Staten Island and Brooklyn. Under the City of Yes ADU proposal, these homes can often qualify for attached or internal ADUs, but with additional fire safety and setback considerations. The rules are not the same as detached homes, and homeowners should understand the limitations before planning.

What ADUs Are Allowed in Semi-Attached Homes

According to draft zoning text:

• Internal ADUs within the existing structure are generally allowed if code compliant.

• Attached ADUs may be permitted but must meet strict fire separation requirements between the primary and attached dwelling.

• Rear yard ADUs are possible, but the location must respect setback rules and access requirements.

• Side yard limitations often restrict expansion since semi-attached homes share a wall.

Key Restrictions for Semi-Attached ADUs

• Fire separation must meet updated residential code.

• No reduction of required side yard on the detached side.

• Egress and access requirements must be met without crossing another property.

• Rear yard coverage limitations apply.

Why This Matters in Staten Island and Brooklyn

Semi-attached homes dominate neighborhoods like Eltingville, Huguenot, Dyker Heights and Bensonhurst. These homes have limited side yard space, which affects where an ADU can be legally placed. Garage conversions are possible if the garage sits fully on the homeowner’s lot.

Homeowner Checklist

• Confirm lot lines and yard widths.

• Verify fire separation requirements.

• Consider internal conversions before external ones.

• Ensure ADU access meets code without crossing shared areas.

Semi-attached ADUs are possible but they require careful interpretation of the zoning.

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Joseph Ranola | Five-Star Staten Island & South Brooklyn Realtor® (30 + Google reviews)
Associate Broker · Matias Real Estate | Founder · Bridge & Boro Team
Serving 103xx and 11209 / 11214 / 11228 | $25 M + closed volume
📞 917-716-1496 | ranolarealestate.com