Compliance

What is a certificate of occupancy in construction?

A certificate of occupancy (CO) is the document a local building official issues once a building passes final inspections, confirming it can legally be occupied for its intended use.

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A certificate of occupancy, usually called a CO, is the building department's final word on a permitted project. Until it is issued, nobody is supposed to move in, open for business, or store inventory in the space. Under the International Building Code, which most U.S. jurisdictions adopt with local amendments, a building cannot be used or occupied, and its occupancy classification cannot be changed, until the building official issues a CO.

The CO is tied to the building permit. It typically records the permit number, address, occupancy group, and the code edition used. Work that was exempt from a permit does not need one.

How a CO is issued on a real job

Picture a $480,000 tenant improvement turning a retail shell into a dental office. The GC schedules final inspections for building, electrical, mechanical, plumbing, and fire. The fire marshal tests the alarm and sprinkler. Once every final passes and any fees are paid, the authority having jurisdiction issues the CO. Only then does the tenant's lease start and the owner's lender treat the job as complete.

If one final fails, say the fire damper access panel is missing, the CO waits. The dentist cannot see patients, and the owner starts looking at the liquidated damages clause.

Temporary certificate of occupancy

The IBC lets the building official issue a temporary certificate of occupancy (TCO) for part of a building before all permitted work is done, as long as that portion can be occupied safely. The official sets how long the TCO is valid. TCOs are common on phased jobs, such as opening floors 1 through 3 of an office building while upper floors are still being finished.

What delays a certificate of occupancy

  • Open inspections or a failed final on any trade.
  • Missing third-party reports, such as special inspection, fire alarm acceptance, or elevator certificates.
  • Site items like parking striping, accessible routes, or landscaping that the zoning approval required.
  • Unpaid permit or impact fees.
  • A change in use that was never permitted, which forces a new review.

CO versus substantial completion

They often happen near the same week, but they are different things. The CO is a government approval. Substantial completion is a contract milestone between owner and contractor, documented with a certificate of substantial completion. Many contracts make a CO one of the conditions for substantial completion, so read yours.

Related terms

See building code, inspection, zoning, and closeout. For residential work, the guide on how to handle permits for residential jobs covers the permit side.

Frequently asked questions

Who issues a certificate of occupancy?

The local building official or building department issues it after final inspections pass. Fire and zoning approvals are often prerequisites.

Can someone move in without a CO?

Not legally in jurisdictions that require one. Occupying without a CO can bring fines, insurance problems, and lender issues. A temporary CO can allow partial occupancy.

Does every project need a new CO?

No. Work exempt from permits does not need one, and many alterations that keep the same use do not trigger a new CO. A change in occupancy classification usually does.

How long does a temporary CO last?

The building official sets the validity period. It varies by jurisdiction and project.

Sources

  1. University of Missouri System Facilities: Code determination 03, use and issuance of certificates of occupancy (IBC Section 111)
  2. Gig Harbor Municipal Code 15.08.050 (local amendment example)
Written and edited by

Maurice Francois writes and edits construction operations guides for Smart Business Automator. More from Maurice on the Scaling Legends podcast.

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