Guides
Slab leaks and tear-out coverage
A sudden slab leak is usually covered for the water damage and the cost of breaking in, not the pipe. How the HO-3 splits it and where company forms cut it off.
A slab leak is a leak in a water or drain line that runs in or under your home's concrete slab. Under the standard HO-3, a sudden leak from a plumbing system is covered for the water damage it causes and for the cost of tearing out and replacing the part of the house that has to be opened to reach it. The pipe itself is not covered, and many company forms cut the coverage back for lines in or below the slab, for slow leaks, or for foundation damage.
This guide describes the ISO HO-3 (form HO 00 03 05 11). Slab leaks are one of the claims where your insurer's own form and endorsements matter most, so find the water-damage language in your policy before you rely on any of this.
What the standard HO-3 pays and does not pay
The HO-3 excludes wear and tear, deterioration, rust and corrosion. A pinhole in a copper line that has been corroding for years is, on its face, in that category. Then the form adds an exception: unless the loss is otherwise excluded, it covers loss to the dwelling resulting from an accidental discharge or overflow of water or steam from within a plumbing, heating, air conditioning or automatic fire sprinkler system on your property. The exception includes "the cost to tear out and replace any part of a building, or other structure, on the 'residence premises', but only when necessary to repair the system or appliance." It ends: "We do not cover loss to the system or appliance from which this water or steam escaped" (ISO HO 00 03 05 11, Maine Bureau of Insurance copy).
The form also says its exclusions for surface water and for "water below the surface of the ground," which includes water that seeps or leaks through a foundation, do not apply to loss by water covered under that exception. In plain terms, a leaking supply line under the slab is treated as a plumbing event, not a groundwater event.
That gives a three-part split.
| Cost | Standard HO-3 | Comment |
|---|---|---|
| Water damage to flooring, baseboards, drywall, cabinets | Covered | Subject to deductible and replacement cost terms |
| Cost to break into the slab or wall and restore it | Covered when necessary to repair the line | This is the tear-out and replace language |
| Repairing or replacing the leaking pipe | Not covered | The system itself is excluded |
| Locating the leak | Varies | The ISO form does not mention it; many company forms or adjusters include it with the tear-out |
| Drying and mitigation | Covered as part of the loss | See reasonable repairs: what you can fix before the adjuster comes |
| Living elsewhere while floors are out | Covered under loss of use if the home is unfit | See loss of use and additional living expenses |
| Foundation heave or cracking from the leak | Disputed | See below |
Where company forms narrow it
The ISO text is the baseline, not a promise. Three changes are common.
Seepage language. Many forms limit the water peril to sudden leaks and exclude constant or repeated seepage over a period. The Texas Department of Insurance compared Texas forms in 2018 and found that some companies' water peril excludes seepage lasting 14 or more days, while others exclude seepage over "weeks, months, or years," and others exclude seepage that results in deterioration, corrosion, rust or rot (TDI, Texas Homeowners Policies, April 2018). A slab leak is often found only after it has run for a while, so the length of the leak becomes the argument. sudden vs gradual water damage: where insurers draw the line covers how that line is drawn.
Below-slab exclusions and limits. Some forms or endorsements cover plumbing discharge only above the slab. The Texas FAIR Plan's optional HO-400 endorsement, in its February 1, 2017 edition, is an example: it covered sudden discharge from plumbing only above the surface of the ground and above and outside the slab or foundation, excluded discharge from plumbing within or below the slab, excluded tear-out of a slab or foundation, and capped the peril at $5,000 per policy period (Texas FAIR Plan Association, Endorsement HO-400). That is one state plan's older edition, not a market standard, but it shows how a form can take slab-line leaks out entirely. Other insurers offer slab or foundation tear-out as a limited endorsement or a sublimit.
Foundation exclusions. Settling, cracking and earth movement are separate exclusions, and an insurer that sees the slab shift will often point to them.
Foundation damage is the contested part
A slab leak can saturate the soil, and the slab can lift, sink or crack. Whether the policy pays for that is a fight with no single answer. Under the ISO structure, the accidental-discharge exception covers loss "resulting from" the discharge, but the earth movement exclusion is written to apply "regardless of whether" the movement is caused by nature or otherwise, and insurers use it. Texas shows how unsettled this was. In 1997 the Texas Department of Insurance issued Commissioner's Bulletin B-0032-97, which took the position that the older Texas HO-B form covers foundation damage from accidental discharge of water from plumbing, in response to a Fifth Circuit decision that read the form the other way (TDI Bulletin B-0032-97). The bulletin concerned the HO-B form specifically. Texas policies today come in many forms, and the Texas Attorney General says most are HO-A policies, which generally cover only sudden and accidental water leaks (Texas Attorney General). See Texas and foundation cracks and settling: what's covered.
If foundation damage is part of your claim, you will probably need an engineer's report on cause and a plumber's report on the leak's duration and origin. engineering reports and causation disputes explains how those reports are used.
A hypothetical claim
Say a pinhole leak develops in a copper hot-water line under the slab of a single-story home. The family notices a warm spot on the floor and a high water bill. These are invented numbers.
- Leak detection company: $450.
- Cutting, removing and replacing concrete to reach the line: $3,000.
- Plumber's repair of the line: $900.
- Flooring, baseboards and drywall damaged by the water: $6,500.
- Drying and mitigation: $1,800.
- Deductible: $2,000.
Under the standard HO-3, the insurer treats the tear-out ($3,000), the water damage ($6,500) and the drying ($1,800) as covered, totaling $11,300. It declines the pipe repair ($900) and may or may not pay for locating the leak ($450). With the deductible applied once and leak detection excluded, the insurer pays $9,300 and the homeowner pays $3,350 out of pocket: the $2,000 deductible, the $900 pipe repair and the $450 detection. If the insurer's form excludes plumbing within the slab, the water damage and the tear-out could be excluded as well, and the homeowner would bear the whole $12,650.
Repair options and what the insurer pays
A plumber can repair a slab leak in several ways. Each changes the cost and the claim.
- Spot repair under the slab. The slab is cut, the soil excavated, and the pipe fixed. This is the case the tear-out wording was written for.
- Reroute. The line is abandoned and a new one is run through the attic or walls. It often avoids breaking the slab, but it is a plumbing upgrade, and the pipe is the part the policy excludes. Some insurers pay what the tear-out would have cost; others pay only for the access actually performed. Ask before you choose.
- Repipe. A whole-house repipe replaces old pipe. Insurers generally pay only for the section necessary to stop the leak and not for a repipe of the house, even if the pipe is failing everywhere.
Supply lines and drain lines. Most people mean a pressurized supply line when they say slab leak. A leaking drain line under the slab is also a discharge from a plumbing system under the ISO wording, but insurers often treat the damp soil, odor and slow seepage that come with it as gradual, and water coming up through a floor drain is a backup, which is excluded unless you bought water backup coverage.
Get written estimates for the route the plumber recommends and for the alternative. The adjuster's scope controls the claim, and a cheaper reroute that your insurer agreed to is better than a costly repair you did first.
What to do, in order
- Confirm and contain. Signs of a slab leak include a warm spot on the floor, the sound of running water with every fixture off, an unexplained jump in the water bill, and a moving water meter dial when everything is off. Close the main shutoff if the leak is active.
- Report the claim before anyone breaks concrete. The adjuster needs to see the source and the damage. Get the claim number.
- Have a licensed plumber or leak detection company document the leak. Ask for a written report that states the location, the type and age of the pipe, the cause and how long the leak likely ran.
- Photograph before and after. The damaged flooring, the slab opening, the pipe section removed, and any moisture readings.
- Dry the structure. Delay invites mold, which is capped or excluded on many policies; read does homeowners insurance cover mold?.
- Keep a loss-of-use record. If floors are torn out and you cannot live in the house, additional living expenses may apply.
- Ask about the next renewal. An older home with a history of pipe leaks can attract underwriting attention; polybutylene, galvanized and other pipes insurers dislike covers pipe types insurers dislike.
Key takeaways
- The standard HO-3 pays for the water damage and the necessary tear-out from a sudden plumbing leak, but not for the pipe that failed.
- Company forms vary more here than almost anywhere: look for seepage limits, below-slab exclusions, tear-out sublimits and foundation exclusions.
- Foundation damage from a slab leak is the most disputed part; expect to need an engineer's and a plumber's report.
- Report the claim before the slab is opened, and get a written plumber's report on cause and duration.
- Choose the repair route with the insurer's scope in hand, because rerouting can change what is paid.