What it is
Legalization means fixing the City’s paperwork so it matches reality. It applies when parts of the building were built or changed without the Department of Buildings approvals—or when what you see at the building no longer agrees with what appears on official records.
Why it matters to address
Unresolved issues can block loans, refinancing, a sale, and insurance. Owners may face mounting fines, stop-work orders, or orders to vacate. Certificates of Occupancy and new permits stall until facts and filings line up.