Service 19
Accessory Apartments & Conversions
Legalize a second unit, garage conversion or two-family use where the code allows it.
Second units are among the most common unpermitted conditions on Long Island, and among the most locally regulated. Egress, parking, ceiling height, owner-occupancy and separate utilities all get examined, and the rules differ between neighbouring towns.
Scope
- Accessory apartment permit applications
- Garage and basement conversion legalization
- Two-family use applications and conversions
- Egress, light, ventilation and ceiling height analysis
- Parking and lot requirement review
- Fire separation and life safety compliance
- Rental permit and registration support
Who we work with
Homeowners with an existing second unit, buyers of properties with one, and owners planning to add one.
Where we deliver this
Across every town in Nassau and Suffolk, the East End and all five boroughs:
- Long Island
- New York City
- The Hamptons
- Hempstead
- North Hempstead
- Oyster Bay
- Glen Cove
- Long Beach
- Babylon
- Brookhaven
- East Hampton
- Huntington
- Islip
- Riverhead
- Shelter Island
- Smithtown
- Southampton
- Southold
Related services
- Professional Engineering Services
- Structural Engineering
- Civil & Site Engineering
- Design & Construction Documents
- Inspections & Site Observation
- Forensic Engineering
- Engineering Reports & Certifications
- Permitting & Expediting
- Violations, Open Permits & Compliance
- Legalizations
- Additions & New Construction
- NYC DOB & Agency Filings
- Pool Design & Permitting
- Health Department Permitting
- Project & Construction Management
- Variances & Zoning Relief
- Property File Review
- Certificates of Occupancy & Compliance
- House Lifting & Flood Elevation
- Wetlands & Environmental Permitting
- Solar Structural Letters
- Storm & Insurance Damage Assessment
- Demolition & Change of Use
- Construction Cost Estimating
Related guides
Common questions
The unit already exists. Can it be legalized?
Often, though it depends on the town, the zoning district and whether the space can meet egress and ceiling height. A site visit and a look at the record answers it.
Does the owner have to live in the house?
Many Long Island jurisdictions require owner-occupancy for an accessory apartment. Which rule applies depends on the municipality.