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Repairing a slab leak ranges from $630 to $4,400, but the national average cost is around $2,300.* A concrete slab foundation supports a home’s weight and houses its plumbing system. Though concrete slab foundations are highly stable and unlikely to have many problems, they aren’t unbreakable. We’ll break down the cost factors so you can budget accordingly.
*Article cost data via Angi, Fixr, and Home Advisor.
Slab Leak Repair Major Cost Factors
The cost of slab leak repair is determined by leak detection, repair method, and labor costs.
Slab leak detection is the first step in repair. The damaged pipe’s location isn’t always obvious, so sometimes a plumber will need to drill holes or run a camera into a pipe to find the leak’s location. Detection can cost anywhere from $150 to $600 depending on the required methods.
Leak Repair Methods
Depending on the leak location, type, and extent of the damage, a professional plumber will choose from a number of repair methods to fix the problem. These methods range from simple sealing and patching to large-scale foundation repair. We’ll explain these methods in a later section.
Cost by Repair Method
Here are some price ranges for common types of slab leak repair.
|Repair Method||Cost Range|
Broken pipe repair
Water main repair
Leak Repair Labor
Slab leaks should be repaired by licensed plumbers, who charge $45 to $200 an hour depending on their years of experience and the repair services required. The bulk of slab leak repair costs go to labor rather than materials. If you require emergency leak repair services, the cost could increase substantially.
Additional Factors Affecting Slab Leak Repair Cost
Here are some common reasons you may encounter additional costs.
The best access point to the leaking pipe may be underground. If so, you’ll need to excavate and remove landscaping features around a portion of the slab. Excavation costs are usually based on the amount of dirt moved, anywhere from $50 to $200 per cubic yard. This dirt will also need to be filled back in afterward.
If your home’s foundation has suffered extensive damage in the form of cracks, shifting, sinking, or erosion, you’ll need to have it fixed to maintain the house’s structural integrity. Crack repair may cost as little as $250 to $800, but some processes, such as mudjacking to level the slab, can cost up to $3,000.
Both plumbing jobs and foundation repair require local building permits, which generally cost between $75 and $200 each. If your home’s water main requires repair, the permit is likely to be costlier. Check with your local permit office to find out what is required.
Subfloor Repair or Replacement
Some leaks can cause water to pool under the wooden subfloor and cause mold, mildew, or warping. When this happens, the subfloor will need to be replaced—a cost of $500 to $1,000. Note that the concrete floor will need to be completely dry before new subflooring can be installed.
Depending on the water leak’s size, damage may not be confined to the subfloor. Flooring materials like carpet and hardwood may be affected, as might baseboards and drywall if the problem is extensive. The cost of drying and repairing the damage depends on the type of leak. Clean water leaks are easiest to remedy at about $3 to $4 per square foot, but gray or black water—which can come from serious sewer line breaks—can cost up to $7.50 per square foot, plus the cost of replacing damaged materials. If the water quality is bad enough, a special remediation team will be necessary.
How to Reduce Slab Leak Repair Costs
Although slab leak repair can be costly, you can keep the overall cost down with these tips.
- Address the problem as soon as you see warning signs to avoid further damage.
- Check your homeowner’s insurance policy to see if it covers slab leaks.
- Unless there’s widespread mold or sewage involved, do as much water damage cleanup yourself as possible.
- If there is a substantial mold infestation, hire professional remediators to mitigate the health hazard. You’ll save on potential medical bills down the line.
- If it’s not an emergency, get estimates from at least three local plumbing services.
Signs of a Slab Leak
Some signs of a slab leak are obvious, such as standing water or wet spots on the floor. But, even if you don’t see puddles, look for the following.
- High water bills with no other obvious cause
- Changes in water pressure from faucets, shower heads, and hoses
- Sound of running water when it’s not in use
- Warm spots on the floor from a hot water line
- Cracks in the foundation
Types of Slab Leak Repair
Here are the most commonly required slab leak repairs.
Sealing and Patching
Patching and sealing alone aren’t enough to fix a slab leak, but they can be part of repair. Minor cracks or holes in the slab, such as those formed by leaks or by drilling to find leaks, will need to be injected with epoxy or patched with hydraulic cement. This will prevent the cracks from widening over time and costs between $250 and $800.
Sealing is also a preventive measure. Coating the slab with $100 to $200 of concrete sealant will keep it from absorbing moisture. These are fairly simple do-it-yourself (DIY) projects and don’t require a plumber.
Repairing Broken Pipes
Depending on the pipe’s location and condition, it may be repairable, rather than requiring rerouting or replacement. Pipes in relatively good condition with small leaks may be sealed with epoxy, which is the most cost-effective method. Other times, pipe repair may require replacing pipe sections that are leaking due to cracks or corrosion. This process can cost between $200 and $2,000, depending on how difficult the pipe is to access.
Water Main Repair
The water main is the entry point for clean water from a municipal water source, so it’s an important pipe that deals with heavy flow. Luckily, it’s also easy to access because it’s typically located at the edge of a concrete slab. Repairing a water main, which feeds all the other water pipes in your home, usually costs between $330 and $1,360, and it doesn’t require as much concrete repair as some other projects.
Pipe lining, also called trenchless pipe repair, is a way of repairing leaks without needing to break up the slab or even dig into the ground. Basically, the plumber feeds a new liner into the existing pipe and creates a new channel for water to flow through without needing to remove and replace the old pipe. This is a much less invasive process, but it’s not possible for all pipes within a slab. Because it involves the use of special machinery, pipe lining costs between $500 and $2,000 depending on the pipe’s length.
Breaking the Slab
If the broken pipe is located deep within the slab and isn’t a good candidate for pipe lining, contractors must break into the concrete to access it. This is done by removing the flooring and subflooring and using machinery to break up the concrete. Sometimes the flooring can be saved and replaced, but you’ll need to have new concrete poured once the repiping is complete. Breaking a concrete slab can cost $500 to $3,000 depending on how much needs to be demolished and disposed of.
If you don’t want your floors disturbed and trenchless repair isn’t an option, you can request that contractors tunnel beneath the foundation to access the leak. This costs between $900 and $2,000, but it isn’t possible in all areas because the soil needs to be stable enough to continue to support the house’s weight. Tunneling is also not an option in areas with high water tables.
Slab foundation areas that are broken in order to access pipes must be repaired afterwards by pouring new concrete. Unless the slab is severely damaged or sinking, you can typically replace only the broken portion instead of replacing the whole thing. Depending on how much concrete is required, you may pay anywhere from $4,000 to $8,000.
If accessing the pipes within the slab isn’t possible or if there are multiple problems, plumbers may cap off old pipes and reroute your home’s plumbing and water heater to a new location. Typically, this means running new pipes up over the house through the attic. This is a labor-intensive process that requires a significant investment—usually between $4,000 and $15,000 for the whole system—but it’s less invasive than breaking into a foundation or tunneling beneath it.
How to Hire a Professional
Unfortunately, slab leak repair is not a DIY project—it requires special equipment and expertise that most homeowners don’t have, so it should only be completed by a licensed plumbing company. Here’s how to find the right contractor for the job.
- All states require plumbers to have a special license, so ask for proof of up-to-date licensure.
- All contractors who work on your home should be bonded and carry valid insurance.
- Look each potential plumbing repair company up on the Better Business Bureau website. You’ll see how the BBB has rated the company, whether it’s accredited, and how customer complaints are handled.
- Check other customer review sites such as Trustpilot and ask the company for recent references.
- When possible, get an itemized estimate.
- Make sure you understand the project and payment timelines.
If you suspect a leak in your slab foundation, call a professional plumber as soon as possible. Left unchecked, a slab leak can cause substantial water damage, and a health hazard if mold or bacteria are left to grow. Your best bet is to catch it and have it repaired before the slab is compromised, so know the warning signs and act quickly.
Slab Leak Repair Cost FAQ
How urgent is a slab leak?
Because your foundation is crucial to your home’s stability and a leak can erode both soil and concrete over time, a slab leak is an urgent problem. While it might not warrant emergency repair unless there is flooding or standing water, you should have any slab leak inspected as soon as you suspect you have one.
How do you fix a leak under a slab?
Once a leak’s location has been pinpointed, the most common repair method is to break into the slab to access the pipes. In some cases, it may be possible to tunnel into the ground to get to the pipe or insert a lining into the old pipe to fix it. Finally, the old pipes can be capped off and the plumbing system can be rerouted to a new location.
How long does a slab leak take to fix?
Depending on the problem’s severity and repair method, plumbers can usually fix a slab leak in one to three days.
Are slab leaks easy to fix?
Slab leaks should only be fixed by licensed plumbers who have the training, tools, and experience to do the job properly.
Does a home warranty cover slab leaks?
Most home warranties don’t cover slab leaks. However, your insurance company may cover repairs if the slab leak is the result of a covered event such as a natural disaster.