The Certificate of Occupancy (CO) is one of the most important yet often overlooked documents in a real estate transaction. It defines the legal use of a building and can directly impact your investment, your insurance, and even your ability to obtain a mortgage.
What Is a Certificate of Occupancy?
A Certificate of Occupancy is a document issued by the New York City Department of Buildings (DOB) that certifies a building's legal use and type of occupancy. It specifies:
- The number of dwelling units permitted
- The type of use (residential, commercial, mixed-use)
- The number of floors and rooms
- The building classification
- Any special conditions or restrictions
Why the CO Matters to Buyers
Legal Use vs. Actual Use
One of the most common problems we see is a property being used in a way that does not match its CO. For example, a two-family house being used as a three-family, or a basement being rented out as a separate apartment when the CO only permits use as storage. These discrepancies can create serious legal and financial problems.
Common CO Issues
- Illegal conversions: A basement or attic converted to living space without proper permits or an updated CO
- Commercial use in residential zones: Operating a business from a property zoned only for residential use
- Missing CO: Older buildings (pre-1938 in NYC) may not have a CO on file, which requires a Certificate of Completion or Letter of No Objection instead
- Expired temporary CO: New construction may have a Temporary Certificate of Occupancy (TCO) that has expired
Consequences of CO Problems
- Mortgage denial: Lenders may refuse to finance a property with CO issues
- Insurance problems: Insurance companies may deny claims related to illegal use
- DOB violations and fines: The city can issue violations and impose daily fines for illegal occupancy
- Tenant liability: If tenants are injured in an illegally converted space, the landlord faces significant legal exposure
- Difficulty selling: CO issues will surface when the next buyer's attorney conducts due diligence
How to Check the CO
You can look up a property's Certificate of Occupancy through the NYC Department of Buildings website (BIS — Buildings Information System). Enter the property address to find:
- The most recent CO or TCO on file
- Any open DOB applications or permits
- Active violations
- Complaints history
Your Attorney Should Verify
While you can do a preliminary check yourself, your real estate attorney should conduct a thorough review of the CO as part of the due diligence process. The attorney will compare the CO against the actual property conditions, identify any discrepancies, and advise you on the risks and potential remediation steps.
Conclusion
Never assume that a property's actual use matches its legal use. The Certificate of Occupancy is a critical document that affects your legal rights, your financing, and your investment. Always check the CO — and always have your attorney verify it before closing.
Contact Huang & Associates, P.C. for a thorough property review before your next purchase.