What it means
A catastrophe can damage thousands of properties over several days, rather than producing one cleanly timed accident, and the clause turns that spread of losses into a contractual unit that the insurer and reinsurer can price, report and settle. The Singapore Reinsurers Association describes consecutive periods commonly of 72 or 168 hours, especially for property catastrophes.
These are common examples, not universal requirements, since the actual treaty can specify different windows for different perils and locations. The insurer that buys reinsurance is the cedant, and it usually keeps an agreed first slice of loss, called the retention, before the reinsurer covers an excess layer up to its limit.
Grouping losses matters because a separate occurrence can mean another retention. Conversely, one large occurrence can exhaust a single limit even when the cedant still has capacity available for another event.
A treaty may allow the cedant to choose the start of a window, subject to restrictions. Selecting the period with the most damage can improve recovery, but that choice must follow the wording rather than hindsight alone.
The reporting date is also not necessarily the damage date, since a claim reported on Monday might concern damage suffered on Saturday, and delayed discovery does not automatically place it inside a later window. Loss adjusters therefore need evidence about when damage happened, and weather records, policyholder accounts, inspections and location data can matter as much as the eventual repair invoice.
An hours clause works alongside the definition of the peril, territory and occurrence. It does not make every loss during a storm recoverable, waive exclusions, or replace the underlying policy's coverage tests.
For managers, the important issue is the difference between insured customer losses and recoverable reinsurance losses. A company can owe policyholders money that falls outside its reinsurance window, leaving an unexpected capital and cash requirement.
Finance teams should therefore test several plausible loss timelines before renewal.
In practice
Real-world examples.
Example
An insurer records 18 million dollars of hurricane damage over five days. Its 72-hour clause requires it to identify the covered three-day period rather than submit the five-day total as one automatic recovery.
Example
Two storms strike different regions during the same week. A time overlap alone does not combine them if the treaty requires losses to arise from the same event or cause.
Example
A warehouse owner reports roof damage a week after an earthquake. The adjuster establishes that the damage happened during the covered occurrence, so a late report is considered separately from the time-of-loss test.
Formula
Calculation
For a simple excess-of-loss layer, recovery equals the smaller of the layer limit and covered occurrence losses minus the retention, with no recovery below zero. This simplified calculation ignores exclusions, expenses, reinstatements and aggregate limits.
Suppose losses within an eligible 72-hour window total 12 million dollars, the retention is 3 million and the layer limit is 8 million. Recovery is the smaller of 8 million and 12 million minus 3 million, so the reinsurer pays 8 million.
The insurer retains 4 million of that occurrence, including 1 million above the layer. If another 2 million of otherwise insured damage lies outside the chosen window, that amount cannot simply be added to this recovery; its treatment depends on the treaty's remaining wording.Case study
Seen in the real world.
The following is an illustrative and fictional case. Cedar Vale Insurance sold commercial property cover along a coast and bought catastrophe reinsurance with a 72-hour windstorm window. After a slow-moving cyclone, its claims team initially projected recovery from all six days of damage. Treasury used that estimate to plan payment of contractors and emergency accommodation providers. The reinsurance team reconstructed damage by location and time.
The permitted window captured most losses, but repairs outside it could not all be included in the same occurrence. Cedar Vale revised its cash forecast before paying the largest claims and used its reserve funds for the gap. At renewal, it compared the extra premium for broader occurrence wording against the capital needed for long storms. The lesson was not that a longer window is always better. It was that treaty assumptions must enter the operating cash forecast before a catastrophe exposes the difference.
Watch out
Common mistakes.
- Treating a time window as the whole coverage test. Peril, cause, territory, exclusions and limits still apply.
- Using the date a claim arrives as the date damage occurred. That can put losses in the wrong contractual occurrence.
- Assuming every new window creates fresh capacity. Retentions, reinstatements and annual aggregate limits can restrict later recovery.
Questions
People also ask.
Is an hourly clause the same as a claims deadline?
No. It normally concerns the period during which damage occurs, while notice and submission deadlines are separate contractual duties.
Who chooses the start of the window?
The treaty decides. Some wording gives the cedant a choice, but conditions can prevent overlapping windows or arbitrary regrouping.
Does it always benefit the reinsurer?
No. It can limit liability, but aggregation can also help a cedant exceed its retention and recover losses that would otherwise remain below it.
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