The 80% Coinsurance Argument That 'No Single Fire Could Ever Be That Big'
A Norman, Oklahoma landlord insures a 12-unit brick apartment building on a replacement-cost commercial property form with an 80% coinsurance clause and a $2,500 deductible. The building's replacement cost at the time of loss is $1,200,000. To hold the premium down, the owner purchased a $720,000 limit. A kitchen fire causes $300,000 of damage, and the adjuster confirms that repair will cost exactly $300,000 and that a full rebuild would cost $1,200,000. The policy applies the coinsurance factor to the loss after subtracting the deductible. The owner objects: he has never had a total loss, $720,000 is "more than enough for any single fire," and he wants the penalty removed or an agreed-value endorsement issued instead.
1. Calculate what the insurer pays and what the owner absorbs, and explain why the owner's objection fails.
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Step 1 - limit required to avoid a penalty: 0.80 × $1,200,000 = $960,000.
Step 2 - coinsurance ratio: limit carried ÷ limit required = $720,000 ÷ $960,000 = 0.75.
Step 3 - loss after deductible: $300,000 − $2,500 = $297,500.
Step 4 - payment: 0.75 × $297,500 = $223,125.
Owner's out-of-pocket: $2,500 deductible + $74,375 coinsurance penalty = $76,875.
The objection fails because coinsurance does not measure the size of the loss. It measures whether the insured carried premium for a fair share of the value exposed to loss. The test is applied at the time of loss, comparing the limit to the required percentage of value, regardless of whether the loss is $3,000 or a total. A building that can burn to the ground is exposed to a total loss on any given night, and the rate was computed on the assumption that the owner would insure 80% of that exposure. Buying 60% of value for a chance that no large loss occurs is exactly the adverse selection coinsurance is designed to price.
2. The owner asks whether paying for the extra $240,000 of limit is worth it, and whether agreed value solves his problem. Advise him.
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The math favors buying up to $960,000. The added $240,000 of limit is a small fraction of the total property premium, while one $74,375 penalty in this claim alone would have paid for many years of the additional limit. A second insured building or a second large loss compounds the case. Recommend at minimum a limit equal to 80% of current replacement cost, and re-index it at each renewal because construction costs move.
On agreed value: an agreed-value endorsement suspends the coinsurance calculation for a stated amount accepted by the underwriter. It is useful, but understand three limits. It does not raise the limit - the agreed amount is still the most the insurer pays. It usually requires a current statement of values or appraisal, and underwriting may apply a higher rate or decline. It does not protect against underinsurance; if the agreed value is set at $800,000 on a $1,200,000 building, the total-loss shortfall simply becomes a contractual certainty instead of a penalty calculation.
Other tools to raise: a blanket limit across locations (watch the margin clause, which can cap recovery at a percentage of the last reported values) and inflation guard on the limit. Any of these is a better answer than arguing with the adjuster after the fire.
3. The building is destroyed by a gas explosion three months later. What does the insurer pay, and what lesson should the client take from the two claims together?
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Payment on a total loss: the insurer pays the $720,000 limit (less the deductible per the form's valuation clause), not the $1,200,000 replacement cost. The owner absorbs roughly $480,000 plus the deductible and any debris-removal or ordinance-and-law costs above the limit.
The lesson: the owner's argument was internally inconsistent. He defended the low limit by pointing to the absence of a total loss, but the only scenario in which the limit is tested absolutely is the total loss. A coinsurance penalty is a partial, calculable hit; exhausting the limit is an unrecoverable one. In both claims the deficiency traces to the same decision - insuring 60% of value to save premium.
Practical note: if the property is mortgaged, the lender's loss-payable clause does not fill the gap; it only directs who receives the limit. And ordinance-and-law coverage, if purchased, has its own limit and will not raise Coverage A. Advise the client to correct the limit at the next renewal, and document the recommendation in the file now - the recorded advice is the agency's best defense if the client later claims he was never told.