DayCents

Insurance

Home Insurance Coverage Calculator

Home insurance pays to rebuild, not to replace what you paid. Those are different numbers, and construction costs have moved faster than most policies were updated. Fall below the co-insurance threshold and even a small claim gets reduced in proportion.

Square feet of finished living space.

Ask a local builder or your agent — this is not the price per square foot homes sell for.

Usually set as a percentage of dwelling coverage.

Pays to live elsewhere while the home is rebuilt.

Common for wind, hail and hurricane. Applies to dwelling coverage, not the claim.

Insure below this share of rebuild cost and claims are reduced proportionally.

Coverage meets estimated rebuild cost

$0

Your dwelling coverage covers the estimated cost to rebuild.

Rebuild cost is not market value. It excludes land, which is often a large share of what you paid, and includes demolition and current building codes, which market value does not. Ask your insurer for a replacement cost estimate rather than assuming.

Estimated rebuild cost
$400,000

Not the market value, and not what you paid.

Your dwelling coverage
$400,000
Co-insurance floor
$320,000

Insure below this and claims are cut proportionally.

Payout on a total loss
$400,000
Personal property coverage
$200,000
Loss of use coverage
$80,000
Deductible that would apply
$2,500
You pay on this claim
$2,500
Rebuild cost$400K
Covered$400,000100%

How this calculator works

Rebuild cost is square footage × local cost per square foot. The co-insurance floor is that figure × the requirement, usually 80%. When coverage falls below the floor, claims are multiplied by coverage ÷ floor before the deductible is applied — the standard proportional penalty. The effective deductible is the greater of the flat amount and the percentage applied to dwelling coverage.

Cost per square foot is a rough regional average that varies with finish level, terrain, and local code requirements — a professional replacement cost estimate is more reliable. Ordinance and law coverage, extended replacement cost endorsements, scheduled personal property, and the actual cash value versus replacement cost distinction on contents are not modelled. Flood and earthquake are excluded, as they are from the policy itself.

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Frequently asked questions

How much dwelling coverage do I need?

Enough to rebuild the structure at today's local construction costs — typically area × cost per square foot for your region. It is unrelated to market value, which includes land and reflects location rather than materials and labour.

Why is rebuild cost different from market value?

Market value includes land and location; rebuild cost does not. A house in an expensive area may sell for far more than it costs to build, while an older home with detailed construction can cost more to rebuild than it would sell for. Insuring to market value gets one of those badly wrong.

What is a co-insurance clause?

A requirement to insure at least a set share of rebuild cost, usually 80%. Fall below it and every claim is reduced in the same proportion as the shortfall. Insure a $500,000 rebuild for $300,000 against an 80% requirement and claims pay at 75 cents on the dollar, before the deductible.

How does a percentage deductible work?

It is a share of dwelling coverage, not of the claim. A 2% deductible on $400,000 of coverage is $8,000 regardless of whether the claim is $10,000 or $300,000. These are increasingly standard for wind, hail and hurricane in exposed regions, sitting alongside a lower flat deductible for everything else.

What is extended replacement cost?

An endorsement paying 10–50% above the dwelling limit if rebuild costs exceed it — valuable after a regional disaster, when demand spikes construction prices exactly when many claims arrive at once. It costs little and directly addresses the failure mode this calculator measures.

Does my policy cover flood or earthquake?

Almost certainly not. Standard homeowners policies exclude both. Flood coverage comes through the National Flood Insurance Program or private carriers; earthquake requires a separate policy or endorsement. This calculator does not model either, and neither does your policy unless you bought it.

Disclaimer: DayCents provides this calculator for educational purposes only. Results are estimates based on your inputs and the stated assumptions — they are not financial advice, a quote, or an offer of credit. Consult a qualified financial professional before making major money decisions.