Slab Leaks: How They Occur and 3 Options to Fix Them

A leaky pipe can be a headache, but there’s often a quick, inexpensive fix for this common plumbing issue. On the other hand, a slab leak can be a homeowner’s nightmare – and fixing it is best left to the professionals.

While you can search Google or YouTube for quick solutions to most common home plumbing issues, looking for a guide on how to fix a slab leak will only make you realize how big of a problem you’re dealing with.

When you have a slab leak at home, you need to fix it right away, or you can expect it to wreak havoc on your home and your bank account.

workers making a slab foundation of a building

What is a Slab Leak and How Does it Occur?

According to the Survey of Construction on the Characteristics of New Housing, 63.2 percent of newly constructed single-family homes in 2019 have slab foundations. If you live in Texas or another southwest state, there’s a higher chance your home has a slab foundation, as about 95.6 percent of new homes in the region are built on them.

Slab foundations have been gaining in popularity since the early 1900s because of their practicality, cost-effectiveness, and durability. While there’s a good deal of engineering involved during the construction of a slab foundation, simply put, it is formed by pouring concrete onto the ground. The main water pipes are installed underneath this foundation, and the house is built on top of it.

A slab leak occurs when a water pipe leaks under a concrete slab foundation. Since the water lines are beneath the house, you may not even realize that you have a major plumbing issue developing. 

Some of the most common causes of a slab leak are:

1. Soil Expansion or Contraction

Expansive soil shift is a typical culprit in houses suffering from slab leaks. This swelling and shrinking of the soil happen when the ground conditions change from dry to wet. Texas homes with slab foundations are especially prone to this, as the soil composition in Texas is largely cracking clay, sandy soil, and other ground types prone to vertical or lateral shifting. 

The movement of the soil under the foundation can potentially damage water pipes. The water from the leaking lines can then cause the ground to shift further, triggering a chain reaction that may go unnoticed for some time. 

2. Improper Construction or Plumbing Materials Used 

Another common cause of slab leaks is the improper installation of pipes. If your pipes were bent, dented, or kinked during construction, these damaged areas become weak. They are prone to bursting when subjected to varying water pressure and the abrasive property of the surrounding ground.

Likewise, the choice of plumbing materials can be a contributing factor to slab leaks. Cast iron and galvanized pipes are common in older homes, and while these materials are durable, they are also prone to rust and clogging as they age. Newer homes now use plastic pipes such as PVC (polyvinyl chloride pipe), CPVC (chlorinated polyvinyl chloride pipe), or PEX (cross-linked polyethylene) that are corrosion resistant and easy to work with.

3. Abrasion and Other Outside Pressures

During the course of their use, water pipes are subjected to friction while rubbing against nearby pipes, concrete, soil, and other materials. For hot water pipes, you can add expansion to the list of issues that may cause these structures to leak over time. 

Other factors that may cause slab leaks include growing tree roots, earthquakes, soil erosion, or an underground stream. 

4. Chemistry

The chemistry of water also contributes to the corrosion of pipes. Some water can be too acidic or too alkaline, and these imbalances can corrode pipes. Some types of soil and concrete may also have high alkaline levels, which may also potentially damage plumbing lines.

Slab leaks are silent foundation killers. You must be able to recognize signs that there’s a brewing problem below the foundation of your home.

Common Warning Signs You Have a Slab Leak

When dealing with a slab leak, you may first notice that you’re paying higher water bills. There’s also a good chance that you’ll experience a sudden drop in water pressure. Other homeowners hear a rush of water under their house, even when all faucets are tightly shut.

Below are some of the physical signs that you have a slab leak:

  • There are water spots on your floor.
  • Gaps appear between your flooring and wall.
  • It’s hard to open doors or windows.
  • You notice soft spots, water stains, or bubbling on your flooring.
  • There is an increase in mold and mildew in certain areas of your home.
  • You have a burned-out water pump or water heater.
  • The foundation is cracked.

In the worst-case scenario, slab leaks can lead to the eruption of your floor due to excessive pressure from the leak below. Some even end up with a geyser-like fountain flooding their homes.

With a slab leak, you have a constant source of leaking water that fast-tracks foundation damage. 

3 Options for Fixing a Slab Leak

If you suspect that you are dealing with a slab leak, the first thing you need to do is call a slab leak repair specialist. These experts can diagnose the problem quickly and pinpoint the location of the leak using modern equipment such as electronic listening tools and line-tracing equipment.

If required, sub-slab leak repair services also use water line video inspection to find the exact location of the leak.

Once the location of the slab leak is isolated, you have several options to repair it. Just like hospital surgeries, these can range from non-invasive repairs to major, invasive fixes.

1. Trenchless Slab Leak Repair

Trenchless plumbing repair to fix a slab leak requires minor demolition. Your contractor will only need to create access holes to do the slab leak repair. It is the most non-destructive method available, and it isn’t as costly as the traditional methods used to address sub-slab leaks.

The slab repair specialists will use epoxy pipe liners to seal the broken pipe. They will do a camera inspection to see the extent of the damage. If trenchless repair is viable, they will clean the pipe, place the epoxy pipe liner and inflate it, and then let it cure. The entire process can be completed in a few hours.

If there are badly damaged water lines, they can also do pipe splitting, which involves inserting new pipes that are slightly larger than the existing ones.

2. Pipe Re-Piping or Re-Routing

When multiple pipes are involved, plumbers often opt for re-piping. This method entails installing new pipes to create a leak-free system. 

Re-routing pipes also requires demolition if you have pipes under your floors and inside your walls that must be replaced too. This is the best solution if you only have to replace a small number of pipes.

Pipe re-routing repairs may take several days, depending on the efficiency of your contractor and the amount of work needed. Since it may involve breaking through the slab, you might need to leave your home and stay somewhere else while the work is completed. 

3. Tunneling Under the Slab

Most homeowners who want to salvage their expensive flooring choose tunneling as the method of repair. The repair crew will keep the mess out of your home, so you can stay during the repair process.

The slab leak repair crew will dig working tunnels under your home while making sure the structural integrity of the house is not affected. They will perform the necessary repairs, and then return the soil that was removed.

How Long does it Take to Fix a Slab Leak? 

Slab leak repair can take anywhere from a few hours to around three days, depending on the method used for the repairs. 

Finding the leak may involve an inspection that will set you back from $150 to $400. The slab leak repair itself may cost as little as a few hundred dollars for an epoxy repair, or up to between $2,000 and $6,000 depending on the method, materials, and labor that will be needed during the process.

Cracks in your foundation typically cost $250 to $800 to repair. If your foundation needs leveling, this will cost around $1,000 to $3,000 on average.

The total cost may or may not be covered by your homeowner’s insurance. It’s best to ask your insurance provider whether this type of damage is included on your policy before you begin seeking repairs.

Tap the Services of Slab Leak Specialists in Texas

When it comes to slab leak repair, trust the experts with proven experience in the field. Remember that you need to address slab leaks as soon as possible to avoid more serious problems.

Accurate Leak and Line can fix slab leaks and plumbing leaks using trenchless plumbing repair and traditional plumbing repair methods. Contact us today!