The Warehouse Coinsurance Dispute
A Nebraska commercial building owner insures a warehouse for $600,000 under a replacement-cost policy with an 80% coinsurance clause and a $5,000 deductible. The building's replacement cost at the time of loss is $1,200,000. A windstorm tears off part of the roof and allows rain in, causing $200,000 in covered damage. The policy limit is $600,000. The owner argues that because he paid for $600,000 of coverage and the loss is only $200,000, the insurer should pay $195,000 after the deductible. The adjuster calculates a smaller payment.
1. Calculate the coinsurance payment and explain each step.
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Step 1 - Required insurance. 80% × $1,200,000 replacement cost = $960,000.
Step 2 - Coinsurance ratio. Limit carried ÷ required insurance = $600,000 ÷ $960,000 = 0.625 (62.5%).
Step 3 - Apply the ratio to the loss. $200,000 × 0.625 = $125,000.
Step 4 - Apply the deductible. $125,000 − $5,000 = $120,000.
Step 5 - Check the caps. The payment cannot exceed the policy limit ($600,000) or the actual covered loss ($200,000). $120,000 is below both, so the insurer pays $120,000.
The owner's error is applying the deductible to the full loss and ignoring the coinsurance ratio. The ratio is the mechanism that makes the insured share the cost of underinsurance.
2. How would the payment change if the limit were $1,000,000? What if it were $960,000?
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At $1,000,000: ratio = $1,000,000 ÷ $960,000 = 1.0417. Applying that to $200,000 gives about $208,333, but the insurer never pays more than the covered loss. Payment is capped at $200,000, then reduced by the $5,000 deductible = $195,000. Carrying more than the required amount does not create a profit; it just removes the coinsurance penalty.
At $960,000: ratio = 1.0. The full $200,000 loss is payable, less the $5,000 deductible = $195,000.
Lesson: once the limit reaches the coinsurance requirement, additional insurance does not increase payment on a partial loss, but it protects against a larger loss and avoids a penalty if values rise. The insured should review values at renewal because replacement cost changes.
3. The owner says the coinsurance clause is unfair because he never expected a total loss. Explain the purpose of the clause and the risk the owner accepted.
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Coinsurance is a rate-and-risk-sharing device, not a penalty. The insurer sets rates assuming the insured carries a stated percentage of value. If the insured carries less, the premium collected is inadequate for the exposure, so the insured shares the loss in the same proportion as the underinsurance.
Risk accepted: the owner chose a $600,000 limit against a $1,200,000 replacement cost-50% of value when 80% was required. A partial loss triggers the penalty just as a total loss would, because the coinsurance test is based on the limit versus the value at the time of loss.
Alternatives to consider:
- Increase the limit to at least $960,000 and update values annually.
- Ask about an agreed-value or margin clause, which can reduce uncertainty but is not free.
- Consider a higher deductible to control premium instead of cutting the limit.
Judgment point: the owner's expectation that “the loss is small, so the limit should not matter” is exactly the misunderstanding coinsurance is designed to test.