Babylon, NY Accessory Structures: ADU Rental Restrictions (2026)
Key Facts
- Governing section
- § 153-18.D
- Minimum unit size
- 350 habitable sq ft
- One unit capped
- at 3 rooms
- No detached-building units
- main dwelling only
- No cellar units
- any part of unit
Summary
Town of Babylon accessory apartments must be at least 350 square feet, capped at three rooms, and can't sit in a separate building or in the home's cellar.
Each dwelling unit must have a minimum of 350 habitable square feet. One of the dwelling units shall be limited in size to a total of three rooms, not including a kitchen, a living room or bathrooms. No rental unit may be contained in any building or structure other than the main dwelling. No part of the rental unit may be contained in the cellar. This section shall apply to all new accessory apartment applications and all pending accessory apartment applications not yet decided by the Board and shall not apply to renewal applications and transfer applications. [Amended 9-2-2003 by L.L. No. 17-2003; 10-7-2003 by L.L. No. 23-2003]
E. The dwelling shall have only one front entrance; all other entrances will be on the side or in the rear of the dwelling. However, this requirement may be waived by the Commissioner of Planning and Development or his designee if, in his discretion, he determines that the additional door is in existence and is in keeping with the general character of the area. An entrance leading to a foyer, with entrances leading from the foyer to the two dwelling units, will be acceptable. The Board may waive these requirements if it finds them not to be feasible and upon recommendation of the Commissioner of Planning and Development.
F.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: rev 4941158; v66 updated 2026-05-13; through 05-13-2026).
Full Breakdown
Town of Babylon Code § 153-18.D sets the physical limits on a legal accessory apartment: each dwelling unit needs a minimum of 350 habitable square feet, and one of the two units in the home is capped at three rooms, not counting the kitchen, living room or bathrooms. The rental unit can't be placed in any building or structure other than the main dwelling, no freestanding garage or accessory-building apartments, and no part of it may be located in the cellar. The limits apply to new and pending applications, not renewals or transfers already approved.
Violations & Fines
Renting an accessory apartment that violates the size or location rules, including one built into a detached garage or cellar, is punishable under § 153-21: fines from $500 to $1,500 on a first offense, up to $2,500 for repeats.
Frequently Asked Questions
Can I put an accessory apartment in my detached garage?
Is a basement apartment allowed?
Sources & Official References
Other rules in Babylon
New York rules heatmap·Compare Babylon to another location·View the New York accessory structures overview
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