Written by

Jennifer Carlson

May 20, 2024

Edited by

Kristen Cramer

Fact-checked by

Tara Farmer

Average cost to fix a slab leak

Concrete slab leak repair costs $500 to $3,500 for installing a pipe lining. Digging into the foundation and replacing damaged pipe costs $700 to $5,000 on average. Completely replacing the slab costs $5,400 to $10,800. The final cost depends on the scope of the damage, repair method, and leak location.

Sealing cracks

Sealing cracks in a concrete slab costs $100 to $200 on average, depending on the size of the crack. Large cracks indicate a more complex problem that may need larger-scale work, like a partial or full slab replacement. Sealing is also preventative as it keeps the concrete from absorbing moisture.

Patching

Using patching to repair a foundation costs $250 to $800, depending on the scope of the damage or number of cracks. Patching is just one element of fixing a leak and won’t solve the problem on its own. Most professionals use epoxy or hydraulic cement to patch.

Replacing pipes

Replacing plumbing costs $0.40 to $8.00 per linear foot, or $200 to $2,000 total, depending on the material. Instead of completely rerouting plumbing, plumbers can remove and replace the damaged section. They may also be able to seal pipes in relatively good condition with epoxy or another sealant.

Repairing a water main

Fixing your water main costs $400 to $5,000 depending on the damage and if it's a repair or replacement. The water main is somewhat easy to access because it’s on the edge or exterior of the slab. This vital fixture connects all your home’s piping to the municipal water supply or your well.

Digging

Breaking the slab or digging a trench to get to a badly damaged pipe will cost $500 to $3,000. Sometimes you can save any existing flooring over the concrete. Excavation services cost $2.50 to $15.00 per cubic yard or $100 to $300 per hour.

Pipe lining

Installing a pipe lining instead of replacing a damaged pipe costs $500 to $3,500. Cured-in-place pipe lining (CIPP) costs $90 to $250 per linear foot and coats the inside of damaged piping instead of digging it up and replacing it. This method is expensive but does not require any digging or excavation.

Rerouting plumbing

Instead of digging into the slab, you can close off your existing plumbing and reroute the lines. Rerouting plumbing costs $3,900 to $7,500 on average. This is a complex, time-consuming project but is often less invasive than digging into a home’s foundation.

Replacing slab

Replacing a concrete slab costs $6 to $12 per square foot or $5,400 to $10,800 total on average. If you only need to break part of the slab and the rest of it is in good condition, you may only need to replace the broken section instead of the whole thing.

Slab water leak repair cost factors

Several factors influence the final repair cost:

• Inspection: If you can’t find the leak yourself, a foundation inspection costs $300 to $750. A professional will look at the entire slab, find leak entry points, and determine the scope of the damage.

• Method: The leak type and extent of the damage will determine the repair method, which ranges from simple patching to a complete replacement.

• Location: Repairing a leak in an easy-to-reach area like a garage or utility closet costs less than a leak under a kitchen or bathroom.

• Disposal: The contractor will have to remove any debris or concrete pieces. Ask them if they included this service in their estimate or if they’ll add a disposal fee later.

• Permits: A permit for plumbing jobs costs $30 to $500. Many contractors include the cost of permits in their overall cost.

• Emergency repairs: Emergency plumbing costs $120 to $450 per hour if you need help on nights, weekends, or holidays. Calling right away will cost a bit more in the short run, but you’ll end up spending much more if you wait until the damage is severe.

• Mold: Mold remediation costs $1,500 to $6,000 for the average remediation job. Leaks can potentially cause major mold damage, so address the problem as soon as possible to prevent further damage and health complications.

Labor

Plumbers charge $45 to $150 per hour to fix slab leaks, depending on the complexity of the repair and how much experience the plumber has. More experienced plumbers cost more upfront, but they have the expertise to get the repair done right the first time, which can prevent more repairs later.

Signs of a slab leak

Some signs of a leak are obvious, like visible water on the floor. Others are less clear:

• Cracks in your foundation

• Abruptly high water bills

• Sudden changes in water pressure

• Hearing running water when all fixtures are off

• A warm area on the floor over hot water pipes

Slab leak repair FAQs

What is a slab leak?

A slab leak involves broken or damaged pipes underneath a concrete slab foundation or a crack in the slab that lets moisture in. The most common slab leak causes include:

• Corroded cast iron or other metal pipes

• Stress on the pipe from excessive heat or pressure

• Weak points in plastic or PEX pipes

• Damage from hard or acidic water

Does homeowners insurance cover slab leak repair?

Your homeowners insurance policy may cover slab leak repairs if the leak was directly caused by a covered event. These are usually natural disasters like an earthquake, severe flood, frozen pipes, or a tree falling on your home.

How long does it take to repair a slab leak?

Plumbers can usually fix a slab leak in 1 to 3 days, depending on the leak severity and repair method. If the leak causes damage to flooring or cabinets, the repair may take several weeks, including the delivery of new materials.

How do you fix a leak under a concrete slab?

Once the plumber pinpoints the leak’s location, they normally either break into the slab to access the pipes or insert a liner without breaking the slab. In some situations, they can cap off the old pipes and reroute the plumbing system to a new location.

Getting estimates from slab leak repair companies

Before hiring a leak repair company or leak detection company near you, be sure to:

• Get at least 3 in-person estimates to compare. Beware of companies who recommend a full slab replacement without a thorough inspection.

• Look for companies with positive reviews on HomeGuide and Google.

• Choose a licensed, bonded, and insured company with a solid track record.

• Avoid extremely low prices as this could indicate poor-quality work.

• Ask for a written estimate and warranty before they start the repair.

• Avoid any large, upfront payments. Work out a payment schedule for large jobs.

Questions to ask a leak repair professional

A trustworthy repair professional should be able to answer these questions before you hire them:

• Is your company licensed, insured, and bonded?

• How long have you been repairing slab foundation leaks?

• Can you give me a list of references I can contact?

• Can you give me an itemized quote?

• Will this repair require a permit? Will you obtain it?

• Does your quote include all labor, materials, disposal fees?

• Are there any other potential expenses I should be prepared for?

• Do you have experience with homeowners insurance claims?

• How long will the repair take?

• What does the warranty include?

• Can we set up a payment schedule?

• Do you offer financing for large repairs?