Nobody reads a policy properly until they need it. By then the useful questions have already gone unasked. These are the clauses that most often surprise people at the worst possible moment.

1. Conditions precedent to liability

Some obligations are not merely good practice — compliance is a precondition of cover. Alarm maintenance, key-holding arrangements, hot works permits and locking conditions all appear in this category. Breach one, and the insurer may decline regardless of whether it contributed to the loss.

2. Unoccupancy clauses

Cover on a property often narrows sharply once it has been unoccupied for a defined period — typically thirty or forty-five days — and may require weekly inspections and services to be isolated. Seasonal sites and premises between tenants are the usual casualties.

3. Late notification

Claims-made policies respond to notification, not to the incident. A circumstance that might give rise to a claim usually has to be notified during the policy period. Waiting to see whether something develops into a dispute is the fastest way to lose cover for it.

4. Contractual liability assumed

Liability policies cover what you are legally liable for, not everything you have promised in a contract. Broad indemnity wording accepted during commercial negotiation can sit entirely outside the policy that was meant to support it.

5. Wear, tear and gradual deterioration

Insurance responds to sudden and accidental events. Corrosion, gradual leakage and deferred maintenance are excluded almost universally — and a slow failure that ends in a sudden one is frequently argued on those grounds.

The practical answer

Ask three questions at every renewal: which conditions are precedent to liability, what notification obligations apply, and where does the policy stop following our contracts. Fifteen minutes of discomfort now is a far better trade than a declinature later.