Key takeaways
- The dwelling limit is a rebuild cost. Insurance does not cover the land, so market value measures the wrong thing — it can sit either side of replacement cost.
- The insure-to-value floor is commonly 80 to 90 percent, not a flat 80 percent, and which applies is a feature of your policy.
- Falling below it reduces what is paid "even if it's a small loss" — it is a discount on ordinary claims, not just a problem in a total loss.
- Extended replacement cost is a percentage buffer above your limit; guaranteed replacement cost rebuilds regardless of the limit. They are not the same promise.
- We will not give you a cost per square foot. Get your insurer's estimate and check its inputs — that is where the errors actually are.
Not sure whether your dwelling limit would actually rebuild your house? A licensed agent can walk through the estimate with you.
Call [PENDING][PENDING]. Calls are answered by [PENDING], a licensed insurance agency (NPN [PENDING]). HomeCoverDesk is not affiliated with any insurer. Calls may be recorded or monitored for quality and training purposes. Our partner does not offer every insurer or every product available in your state.The number is not what your house is worth
The most common way this goes wrong is not carelessness. It is using a sensible-looking number that measures the wrong thing.
Home insurance covers the building. It does not cover the land under it. So the market value of the property — which is mostly a statement about location and about the property market — is not the measure. California's insurance department is direct about it: the limit should reflect “the cost of labor and materials necessary to rebuild the dwelling, not fluctuations in the real estate market”.
Depending on where you are, replacement cost can sit well above market value or well below it. In an expensive market with modest houses, rebuild cost is often far lower than sale price. In a cheap market with a large or unusual house, it is often far higher. Neither case tells you anything about the other, and the coincidence when the two numbers are close is exactly that.
| Figure | What it is | Why it is not your dwelling limit |
|---|---|---|
| Replacement cost | “The amount it would take to replace or rebuild your home or repair damage with materials of similar kind and quality, without deducting for depreciation” | This one is. It is the cost of labor and materials to put the building back |
| Market value | “A real estate term describing the current value of your home if you were to sell it, including the price of the land” | It includes the land, which the policy does not cover, and it moves with the property market rather than with construction costs. It can sit either side of replacement cost |
| Actual cash value | “The value of your property when it is damaged or destroyed. This is usually figured out by taking the replacement cost and subtracting depreciation.” | It is a settlement basis, not an amount of coverage. It describes how a claim is paid, not how much coverage you bought |
| Assessed value or purchase price | What a taxing authority assigned, or what you paid | Neither has any necessary relationship to what a builder would charge to rebuild the structure today |
The floor, and why it matters on small claims
Here is the part that is usually reported wrong.
Replacement cost settlement is conditional. Wisconsin's insurance regulator states the condition plainly: “To qualify for full replacement cost coverage, the building is required to be insured at 80% to 90% of the replacement cost.” Not 80% flat — a range, and which end applies is a feature of your policy.
And the consequence of falling below it is not confined to a total loss. The same guide says that where coverage falls below the threshold, the insurer “is not obligated to pay the total amount of loss, even if it's a small loss” — the guide's own sentence opens “If you purchase an amount of coverage less than 80% to 90% of the amount required to have replacement coverage”, which is the condition that makes it bite. NAIC puts the mechanism the same way: below 80% of full replacement cost, an insurer “may reduce the amount that it will pay on a claim”.
So the exposure is not the dramatic one people imagine. Neither regulator spells out the arithmetic, but in the standard formula it is a proportional reduction — applied to the ordinary claims that make up almost all claims — a kitchen fire, a burst pipe, a section of roof. Being under-insured is a discount on every settlement, not an insurance policy with a small hole at the far end.
| The common version | What the regulators actually say |
|---|---|
| “You have to insure to 80%” | Wisconsin's guide: “To qualify for full replacement cost coverage, the building is required to be insured at 80% to 90% of the replacement cost.” It is a range set by the policy, not a single national threshold |
| “It only matters if the house burns down” | Wisconsin's guide, on falling below the threshold: your insurer “is not obligated to pay the total amount of loss, even if it's a small loss”. It bites on partial claims — which are the claims people actually make |
| “They just pay a bit less” | NAIC: “If it drops below 80% of the full replacement cost of your home, your insurance company may reduce the amount that it will pay on a claim.” How much less is not stated by either guide. In the standard formula the reduction is proportional to how far below the threshold you have fallen — our reading, not theirs |
| “I set it correctly when I bought the policy” | Construction costs move. A limit that was right at purchase can drift below the threshold without you doing anything, which is what inflation-guard endorsements exist to counter — and they are an estimate, not a guarantee |
Want to know where you sit against the insure-to-value threshold? A licensed agent can tell you what your policy requires.
Call [PENDING][PENDING]. Calls are answered by [PENDING], a licensed insurance agency (NPN [PENDING]). HomeCoverDesk is not affiliated with any insurer. Calls may be recorded or monitored for quality and training purposes. Our partner does not offer every insurer or every product available in your state.Extended, guaranteed, and the difference between them
These two terms are used almost interchangeably in marketing material and they are not interchangeable.
Extended replacement cost pays “your policy limits, plus a certain percentage above those limits”. It is a buffer. The question to ask is what the percentage is — and to notice that because it is a percentage of your limit, an understated limit produces an understated buffer. The error compounds rather than being absorbed.
Guaranteed replacement cost is a stronger promise. California's department states that a policy “cannot be sold as a ‘guaranteed replacement cost’ policy unless it will pay to completely rebuild the home regardless of the coverage limit” — stated flatly in its guide, without a statutory citation behind it. Where it is available it removes the insure-to-value problem entirely. It is not widely available, and it is least available where rebuild costs are most volatile.
| Option | What it pays | The catch |
|---|---|---|
| Replacement cost to the limit | Up to your Coverage A figure, without deduction for depreciation | If the rebuild costs more than the limit, the excess is yours. The limit is doing all the work |
| Extended replacement cost | “Your policy limits, plus a certain percentage above those limits” | A buffer, not a blank check. Ask what the percentage is — and note it is a percentage of your limit, so an understated limit understates the buffer too |
| Guaranteed replacement cost | California's guide states that a policy “cannot be sold as a ‘guaranteed replacement cost’ policy unless it will pay to completely rebuild the home regardless of the coverage limit”. The guide gives no section number, but the rule is codified: Cal. Ins. Code § 10102(e) bars issuing such a policy as guaranteed replacement cost if it carries “any maximum limitation of coverage”, and (f) applies the same bar on renewal | It is not widely available, and availability has tightened in higher-hazard areas. Where it is offered, read whether it is truly unlimited or extended coverage using the word loosely |
| Ordinance or law coverage | The cost of meeting current building codes during a repair or rebuild | Separate from all of the above. Without it, an insurer “may not pay for changes you may need to make to the structure of your home to bring it up to current building codes” — a real exposure on an older house |
Why we will not give you a cost per square foot
You will find a great many pages offering one, and they are the reason so many dwelling limits are wrong.
Rebuild cost per square foot varies by local labor market, by construction type, by finish level, by roof type, by how difficult the site is to work on, and by the year. A national average across all of that is not an average of anything you could build. Worse, it is usually quoted without a date, so it goes on being repeated after it has stopped being true.
What is worth doing instead is unglamorous: get your insurer's replacement-cost estimate, ask what inputs it used, and check those. The estimator is generally reasonable; the inputs are frequently wrong, and they are the part you can actually correct.
| Coverage | Usual relationship to Coverage A |
|---|---|
| B — Other structures | 10%, unless additional premium is paid |
| C — Personal property | 50% is the standard relationship Wisconsin's guide gives |
| D — Loss of use | Normally 20% |
| Personal property away from the premises | Wisconsin's guide does give a figure: its “Typical Coverages” table lists Unscheduled Personal Property off Premises at “10% of personal property” — ten per cent of the contents limit, not of the dwelling limit. Note the scope: that table is presented for Homeowners Form 2, so it is a form-specific illustration rather than a universal rule. Ask what yours is |
Arriving at a number
Nothing here is advice about your property and we have not seen it. This is the sequence the definitions above imply.
| Step | What to do | Why |
|---|---|---|
| 1 | Stop using the market value, the purchase price and the tax assessment | None of them measures labor and materials, and all three include or exclude the land in ways that have nothing to do with rebuilding |
| 2 | Ask your insurer for its replacement-cost estimate and the inputs | Most carriers run an estimator. The inputs — square footage, construction type, roof type, finishes — are where the errors are, and they are yours to correct |
| 3 | Check the finishes, not just the footprint | Two houses of identical size rebuild for very different amounts. Custom cabinetry, stone, plaster, tile roofs and non-standard windows are the usual gaps |
| 4 | Add ordinance or law if the house is older | Rebuilding to today's code is not the same job as rebuilding what was there |
| 5 | Ask where you sit against the insure-to-value threshold | It is the difference between full replacement cost settlement and a proportional reduction on every claim, including small ones |
| 6 | Re-check after any renovation, and periodically without one | An addition changes the rebuild cost immediately. Construction-cost movement changes it quietly |
Corrections to this page (1)
We publish these rather than editing quietly. Our corrections policy explains how we handle errors.
- — We retracted the 10 percent figure for belongings away from the premises, saying neither regulator guide stated one. That retraction was wrong: Wisconsin's guide gives it in its Typical Coverages table as “10% of personal property”, for Homeowners Form 2. We had searched the prose and not the tables. The figure is restored with that scope.
Methodology and sources
The definitions of replacement cost, market value and actual cash value, and the insure-to-value requirement, are quoted from the Wisconsin Office of the Commissioner of Insurance's Consumer's Guide to Homeowners Insurance, PI-015, revision 07/2026. One caution about that guide: its revision code is 07/2026 but its worked example still insures a dwelling for $60,000, so the code does not establish that every sentence in it was rewritten. The definitions we quote from it are stable ones. The parallel statement of the 80 percent threshold is from NAIC's A Consumer's Guide to Home Insurance, 2022. We quote both because they differ: Wisconsin states a range of 80 to 90 percent and NAIC states 80 percent, and reporting either one alone as the rule would be a false precision.
The dwelling-limit framing, the extended and guaranteed replacement cost definitions and the ordinance or law point are from the California Department of Insurance's Residential Insurance: Homeowners and Renters guide, revised May 2024. The guaranteed replacement cost sentence is quoted rather than paraphrased because what a policy may be called is the part that protects a buyer.
Correction, 24 August 2026. This page previously added that the guide “cites no statute” for that rule and told readers to treat it as the department's statement rather than something they could look up. It is statutory. Cal. Ins. Code § 10102(e) provides that a residential property policy “shall not be initially issued as guaranteed replacement cost coverage if it contains any maximum limitation of coverage based on any set dollar limits, percentage amounts, construction cost limits, indexing, or any other preset maximum limitation for covered damage to the insured dwelling”, and (f) imposes the same bar on renewal. We downgraded a statutory prohibition to an opinion because the guide we were reading did not carry the citation — the absence of a citation in one document is not evidence that no statute exists.
Correction, 23 August 2026, itself corrected on 25 August 2026. The derived-coverages table gave 10 percent of the personal property limit for belongings away from the premises. On 23 August we retracted that figure as an industry convention we had absorbed and printed as though sourced. The retraction was wrong and the original figure was right. Wisconsin's guide prints it in its “Typical Coverages” table as “Unscheduled Personal Property off Premises — 10% of personal property”. We had searched the guide's prose and not its tables. The figure is restored, with the scope we should have carried the first time: that table is presented for Homeowners Form 2. This is the second retraction on this site to need retracting, and the rule stands — a retraction is a published claim and needs the same proof as the thing it retracts. The proportionality of the insure-to-value reduction, and the legal status of the guaranteed replacement cost rule, are now marked as our reading rather than the regulators'.
The percentage relationships in the derived-coverages table are the standard defaults those guides describe, not universal rules; several are adjustable for additional premium and your own declarations page governs. Each is stated with what it is a percentage of.
There is deliberately no cost-per-square-foot figure anywhere on this page, and no dollar estimate of any rebuild. We have no defensible source for a national one, the figures that circulate are typically undated, and a number of that kind presented confidently is how dwelling limits get set wrong in the first place. Nothing here is advice about your property. If you find an error, our corrections policy explains how we handle it.
Frequently asked questions
Should my dwelling coverage equal what I paid for the house?
No, and the two figures are not measuring the same thing. The purchase price includes the land, which your policy does not cover, and it reflects the property market rather than construction costs. California's insurance department frames the dwelling limit as the cost of labor and materials to rebuild, not fluctuations in the real estate market. Depending on your area the rebuild cost can be well above or well below what you paid.
What happens if I am under-insured?
Full replacement cost settlement is generally conditional on insuring to a threshold — Wisconsin's regulator describes it as 80 to 90 percent of replacement cost. Below that, your insurer is "not obligated to pay the total amount of loss, even if it's a small loss", and NAIC describes the same mechanism as the insurer reducing what it pays on a claim. The reduction is proportional, so it applies to ordinary partial claims and not only to a total loss.
Is the rule 80 percent or 90 percent?
It depends on your policy, which is why we give the range rather than a single figure. Wisconsin's guide states the requirement as 80 to 90 percent of replacement cost, and NAIC's consumer guide uses 80 percent. The number that governs is the one in your own policy's loss settlement condition, and it is a reasonable question to put to your agent — particularly if your limit has not been reviewed for a few years.
What is the difference between extended and guaranteed replacement cost?
Extended replacement cost pays your policy limits plus a certain percentage above them — a buffer of a stated size. Guaranteed replacement cost pays to rebuild regardless of the limit; California's rules do not permit a policy to be sold as guaranteed replacement cost unless it does exactly that. The two are frequently described in similar language and are materially different promises, so it is worth confirming which one is on your policy.
Does inflation guard mean I do not have to think about this?
It helps and it is not a guarantee. An inflation-guard endorsement raises your limit automatically by an index or a set percentage, which counters gradual construction-cost movement. It does not know about your renovation, your new addition, or a local spike in labor costs after a regional catastrophe. It is a reason to review less often, not a reason not to review.
How much does it cost to rebuild per square foot?
We will not give you a number, and we would treat any site that does with suspicion. Rebuild cost per square foot varies by local labor market, construction type, finish level, roof type, site access and year — a national average across all of that is not an average of any house you could actually build, and the figures that circulate are usually undated. Ask your insurer for its replacement-cost estimate and check the inputs it used.
Do I need ordinance or law coverage?
It depends on the age of the house and your local code, but it is worth checking rather than assuming. It covers the cost of meeting current building codes during a repair or rebuild. California's department states that unless your policy has this coverage, your insurer may not pay for changes needed to bring your home up to current codes — and on an older house, rebuilding to today's code is a materially different job from rebuilding what was there.