Certificates of Occupancy vs. Letters of No Objection

A Certificate of Occupancy is a government-issued document that specifies the legal use and/or occupancy of a given building.

For instance, a CO might designate a house as a two-family dwelling, rendering it illegal for the owners to rent out space to a third family. A new CO is issued when a construction project will either create an entirely new building or change how an existing building will be occupied or used.

Normally, a building can’t be legally used or occupied without a CO. However, COs only began to be issued after 1938, so buildings built before then that haven’t been modified since may not have one. If you need a CO to do work and your building doesn’t have one, you may request a “Letter of No Objection” (LNO) from the Department of Buildings. A LNO means what it states–the DOB has no objections to your changing the use, occupancy, or egress of a building.