What it means
A standard commercial property policy lists what it will and will not pay for, and the exclusions are usually where the real money sits: flood, earthquake, earth movement and sometimes windstorm in coastal areas. Difference in conditions cover is bought as a stand-alone contract, often from a different insurer, to pick up some or all of those excluded perils.
The two policies are designed to interlock so that between them the business has close to all-risk protection. Finance teams care because an uninsured catastrophe is not a small line item; it is a solvency question.
A single flood can destroy inventory, equipment and months of trading, and lenders often write covenants requiring evidence that named perils are insured. Buying DIC cover converts an unpredictable and potentially fatal loss into a known annual premium.
In practice the broker maps the primary policy's exclusions, then places a DIC policy with its own limit, sublimits and deductible for those perils. The DIC policy normally responds only after the primary insurer has declined the claim or exhausted its limit, so recoveries are settled in sequence rather than shared.
Deductibles on catastrophe perils are often expressed as a percentage of the insured value rather than a flat dollar amount. Two variants are worth recognising.
Difference in limits cover tops up a primary policy whose limit is too low for the exposure, while difference in conditions proper addresses perils the primary policy excludes entirely, and many contracts do both, described as DIC/DIL. Multinational groups also use DIC/DIL wrappers to top up thin local policies in countries where they are required to buy insurance from a domestic carrier.
Treat the premium as an operating cost and the deductible as a planned worst-case cash outflow that belongs in your liquidity model. Review the cover whenever asset values, locations or lender requirements change, because a limit set five years ago rarely matches today's replacement cost.
In practice
Real-world examples.
Example
A grocery chain with 40 stores along a coastal strip holds a property policy that excludes named windstorm. Its broker places a DIC policy covering windstorm with a $25,000,000 limit and a 3% deductible on the insured value of each damaged location. When a storm damages six stores, the primary insurer declines and the DIC policy funds the rebuild.
Example
A precision engineering firm in an earthquake zone owns $18,000,000 of machinery that its main policy will not cover for earth movement. It buys DIC cover for earthquake only, at a limit of $12,000,000, on the reasoning that a total loss of every machine at once is very unlikely. The finance director records the uninsured tail in the risk register.
Example
A software group with a subsidiary abroad must buy property cover from a local insurer whose maximum limit is $3,000,000. The group places a DIC/DIL policy at head office level that both broadens the perils covered and lifts the effective limit to $20,000,000. Group treasury pays one premium and stops worrying about a mismatch between local and group cover.
Formula
Calculation
DIC recovery = (Loss amount - amount paid by the primary policy - DIC deductible), capped at the DIC limit.
A distribution business suffers $2,400,000 of flood damage to a warehouse and its stock. The primary property policy excludes flood, so it pays $0. The DIC policy carries a $5,000,000 limit and a $250,000 deductible.
DIC recovery = $2,400,000 - $0 - $250,000 = $2,150,000.
That figure is below the $5,000,000 limit, so the insurer pays the full $2,150,000 and the business absorbs $250,000 of cash cost. The DIC premium for that $5,000,000 limit is $95,000 a year, a rate on line of $95,000 / $5,000,000 = 1.9%. Set against a $2,150,000 recovery, the premium covers itself many times over in a single event year.Case study
Seen in the real world.
Harbourline Cold Storage is an illustrative, fictional company operating three refrigerated warehouses in a river delta. Its property policy carried a $30,000,000 limit but excluded flood, an exclusion nobody on the finance team had read closely because the sites had never flooded. During a lender review, the bank asked for evidence that flood was insured and the gap surfaced.
The broker placed a DIC policy covering flood and storm surge with a $10,000,000 limit and a $500,000 deductible, at a premium of $210,000 a year. Eighteen months later a river breach flooded the lowest site, causing $4,100,000 of damage to the building, chillers and stored product. The primary insurer declined, the DIC policy paid $3,600,000 after the deductible, and Harbourline funded the remaining $500,000 from its cash reserve.
The illustrative lesson is that the value of DIC cover is invisible until the year it is needed, so the decision has to be made on exposure rather than on claims history. Harbourline now reviews its exclusion schedule annually alongside its insured values.
Watch out
Common mistakes.
- Assuming an all-risk property policy really covers all risks, when flood and earth movement are almost always carved out.
- Buying a DIC limit equal to the book value of the assets rather than their replacement cost, which leaves the business short after inflation in construction and equipment prices.
- Forgetting that DIC deductibles on catastrophe perils are often a percentage of insured value, so the out-of-pocket cost is far larger than a typical flat deductible.
Questions
People also ask.
Does DIC insurance replace my main property policy?
No, it works only in combination with it, responding to perils or limits the primary policy does not cover.
Can DIC cover include business interruption?
Yes, many policies extend to lost gross profit caused by the excluded peril, and that extension is often the more valuable half of the contract.
Who typically buys DIC cover?
Businesses with concentrated property values in catastrophe-exposed locations, and multinational groups topping up small local policies.
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