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Do You Have a Slab Leak? 5 Potential Causes

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If you’ve lived in the Dallas area for the last four years, you’ve witnessed four of the wettest years on record. If you stick around for the month of May, you’ll likely see even more water around town. May is the typically the wettest month of the year.

Rain isn’t the only thing that’s wet in Texas. Dallas area homes experience a hidden danger when it comes to water—slab leaks.

A slab leak occurs in the hot or cold water pipes underneath the foundation of a home. The heavy rains in the area and the resulting ground shift is one cause of slab leaks.

One thing that worries homeowners about slab leaks is the fact that they’re not like the common leaky pipe under a sink or a dripping faucet. These leaks remain hidden, usually until they cause property damage.

Curious about what else causes this type of plumbing problem? Learn more here about 5 possible causes of slab leaks.

Damage Down Below

Let’s take a minute first and clear up one myth about slab leaks. In most homes, the pipes are under the slab. If you have a slab leak, it’s under the foundation, not in the concrete slab.

That said, damaged plumbing pipes under the slab is a common cause of slab leaks. This usually happens during the building process.

Damage can happen due to improper installation or poor-quality pipes. Since pipes are no longer made from cast iron, they’re susceptible to denting. They’re also susceptible to developing kinks.

Pipes bent or dented during installation can develop leaks. Ignoring signs of leaks under the slab sets you up for significant water damage.

Hint: You can still have leaks in any of the pipes installed behind walls or in ceilings. Don’t forget checking those on a routine basis can help prevent property damage too.

Water Is Abrasive

Have you ever seen exposed pipes when they have water through them? A better question is have you heard them?

When water moves through pipes, they rattle. The force of expansion and contraction due to fluctuations in water temperature causes the noise.

Installing pipes under concrete means it’s normal for rubbing to occur against the concrete surface. Over time, the rubbing causes abrasion. Abrasion leads to pipe leaks.

To be fair, it’s not the water that’s abrasive. Abrasion occurs because of the way pipes behave when water rushes through them.

While the problem of abrasion is more common in hot water lines, cold water lines aren’t immune.

Time Isn’t a Friend

If you live in an older home, it’s more susceptible to developing a slab leak.

When we say older we mean homes built before 1970. In the 1970s plumbing trends moved away from clay and cast iron pipes to plastic. Plastic plumbing pipes made from PVC or CPVC (polyvinyl chloride and chlorinated polyvinyl chloride) are strong, resilient, and cost-effective.

Many older homes still have galvanized steel or copper piping. While durable, over time, both types of piping can develop corrosion.

Remember what we said about hot water pipes and abrasion? The same holds true for hot water lines and corrosion. Due to the reaction between hot water and the pipe materials, pipes can corrode from the outside.

We also mentioned cold water pipes can corrode too. Instead of corroding from the outside, cold water pipes corrode from inside the pipe.

Time also equals years of stress and pressure on pipes. This puts them in the higher risk category for slab leaks.

Pressure on the Pipes

Another possible cause of slab leaks is pressure.

Of course, one type of pressure comes from inside the pipes—water pressure. The kind of pressure we’re talking about right now is pressure put on your pipes.

One cause of pressure on your pipes is shifting soil. When the soil under your home shifts it can cause movement of the foundation. While you don’t feel the movement, it can exert pressure on your pipes.

Another cause of pressure on plumbing pipes is poor construction.

Pressure can crush or crease the pipe. When creases form they can restrict water flow and reduce water pressure.

Ignoring leaks caused by pressure on your pipes can cause serious property damage due to flooding.

You Have Bad Water

Don’t take offense. We know you have clean water in your home. Even so, your clean water won’t protect your home from slab leaks.

When we talk about bad water, we’re talking pH level.

The pH level in your water can determine whether pipes corrode. To make things more confusing, water that’s either excessively alkaline or acidic can corrode pipes.

Know what’s even more interesting about the pH level in your home’s water? A sudden increase in alkalinity could indicate a slab leak.

To understand this, let’s look at concrete. Generally, the concrete used in foundations has a high alkaline level, somewhere between and 12 and 13.

When you have a pipe leak, water can come in contact with the concrete slab. When it contacts the concrete, the water may pick up minerals in the concrete. The result is often an increase in pH.

Most homeowners don’t keep a pH testing kit in their toolbox but your plumber can help you find a good test kit.

Need Help Detecting a Slab Leak?

No homeowner gets excited about a water leak. It is always better when you’re informed rather than caught off guard.

You know now that the most common causes of a slab leak in your home are pressure, abrasion, corrosion, and possibly water quality.

Of course, routine maintenance and plumbing check-ups help ensure your plumbing system continues performing properly. Routine checks can even help prevent slab leaks. If check-ups don’t prevent them, they can at least detect them before you end up with a plumbing disaster.

If you suspect you have a leak in the pipes under your foundation, or any other plumbing problem, contact us today. We have the expertise needed to take care of all your plumbing needs.

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