A certificate of occupancy is issued by the building department (the authority having jurisdiction) after final inspections pass. Those typically include building, fire, electrical, mechanical, plumbing, elevator, health department and sometimes zoning or site inspections. The certificate states the approved use and occupancy classification, and sometimes an occupant load.
Many jurisdictions also issue a temporary certificate of occupancy (TCO), which lets the owner occupy all or part of a building before everything is complete, as long as life safety systems are working. TCOs usually expire and come with a list of conditions to clear.
On construction documents, “CO” usually means change order. To avoid confusion, many teams write “C of O” or “CofO” for the occupancy certificate.
Why it matters
Owners can’t move in, lenders won’t convert construction loans, and tenants won’t start rent without it. Contracts often tie substantial completion to obtaining a CofO or TCO, which means it can trigger the start of warranties, the retainage release schedule and the end of liquidated damages exposure.
Common mistakes
- Treating final inspections as a closeout task instead of scheduling them on the critical path.
- Assuming a TCO means the project is finished, then missing its expiration conditions.
- Mixing up change orders and certificates of occupancy in project logs.
- Leaving inspector comments untracked until the last week.
How os.construction handles it
We’re building closeout tracking where inspections, commissioning and punch items roll up to the substantial completion milestone, so the path to occupancy is visible on one record. It’s in development.