Per project aggregate
An endorsement that gives each construction project its own general aggregate limit, so claims on one job can't use up the limit for yours.
CG 25 03On the certificate
The general aggregate line has boxes for policy, project and location. The project box should be checked.
What to check
The project box and an attached endorsement such as CG 25 03, the Designated Construction Project(s) General Aggregate Limit.
The common gap
A per policy aggregate shared across every job the contractor runs. A busy year elsewhere can leave little of the limit for your project.
Go deeper on forsured.ai: How to check a contractor COI against your project requirements
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General information, not legal or insurance advice. Ask your broker what your policies actually carry.