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What is a Slab Leak and What Causes It?

 ABP-Water leaking from concrete slab porch

What is a Slab?

A slab is a concrete foundation where many houses are often built upon. This foundation is normally incorporated with the home’s water, sewerage, and gas lines. Over time, cracks and holes can develop in the piping system, eventually resulting in leakages that can damage the slab foundation.

What is a Slab Leak?

A slab leakage refers to a water leak that has sprung in the pipe lines installed below your home’s concrete foundation. Although this leak may seem minor, it can eventually cause significant water damage, higher water bills, and ultimately, expensive repairs. Unattended slab leaks can also cause the soil under your home to deteriorate, making your floors rough and the entire house to slowly sink. Given this, it’s important that you become aware of common slab leak signs.

Signs of Slab Leaks

As slab leaks can become serious plumbing problems, you have to take note of the following signs:

1. Unusually High Water Bills

When a leak forms beneath your home, the excess water will escape from your pipes and will be absorbed by the soil. This can lead to significant water loss and increase your water bill at the same time.

2. Strange Odors

The padding beneath your carpet will absorb moisture if there is a leak in the pipe below. This will encourage the growth of mold and similar fungi which will consequently produce strange but strong odors. To prevent this from happening, the padding must be replaced, especially if it becomes too moist.

3. Wet Floors

Wood is the most vulnerable of materials when it comes to water damage caused by a leak. If a pipe is damaged underneath your floors, water will seep into your wood-based living space, resulting in warping and discoloration.

4. Low Water Pressure

A large amount of water can escape from your shower or sink if there is a leak beneath your home’s concrete foundation. This can lead to a dramatic drop in water pressure even when all of your plumbing fixtures are turned off.

What Causes a Slab Leak

Slab leakage can be caused by a variety of factors, but the main reason is the same – water has broken through the concrete foundation of your home and has now reached your living spaces through unnoticed cracks. Nevertheless, a few other factors can come together to cause a leak in the slab.

1. Earthquakes

Ground vibrations caused by earthquakes can cause severe damage to the pipes installed beneath your home and result in slab leaks. Pipe joints can also loosen because of underground tremors. For this, a possible solution is to install a slab leak detection device.

2. Abrasion

The pipes that run from your home foundation to the sinks inside may rub against other objects such as dirt and gravel. This increases the friction between the concrete foundation and the pipes, resulting in untold damage, especially on the pipes’ exterior. This can lead to a pipe leak which can then move near your slab foundation.

3. Strong Water Pressure

When water pressure is too strong, it can cause the pipes to either crack or collapse below your slab foundation. This forces the concrete slab to absorb the excess water and consequently leak.

A water pressure gauge can be installed to determine if your household’s water pressure is too high. The device will measure the PSI (pounds per square inch) of your water line which could be different from the average water pressure rating in the city or suburb where you live. If your water pressure is too high or too low than the average, it can lead to a slab leak.

4. Poor Slab Installation

Poor installation of your home’s concrete foundation is the most common reason for slab leaks. When the ground where the copper pipes are laid down is rough and filled with debris, rocks, and gravel. it can cause pipe dimples. During installation, when the same pipes end up bent, they become susceptible to early damage, notably leaks. These will eventually reach the concrete slab, for which a slab leak repair will be needed.

5. Acidic Water

Hard water can be acidic, but will depend on where you live. In any case, if your water is too acidic, it can cause the pipes located below your slab foundation to crack and degrade. Many homeowners opt to have their water softened to prevent this problem from happening.

6. House Age

Time is another common culprit when it comes to a slab leak. Houses that were built in the 1980’s or even earlier often have copper or galvanized pipes. These are old pipes that are more susceptible to corrosion and cracking. Consequently, they have a higher risk of slab leakage due to prolonged stress or pressure.

7. Deteriorating Water Pipes

Copper and metal pipes will corrode over time, eventually leading to cracks. Even if these are less than a millimeter in length, this is just the start, because eventually, the cracks will grow larger, and this can only mean more water leaks that could reach the home’s foundation.

8. Home Foundation Movement

The ground upon which your house stands can shift once in a while, especially if it was built in an earthquake-prone area. While some movement is normal, if this has damaged the water pipes and has resulted in a slab leak, the situation can get worse. Dirt and other debris can settle in and around the slab foundation and cause it to move further.

The scenario is similar to an earthquake, but in this case, the disaster happens slowly and over a prolonged period. As the ground further shifts, it can put extra pressure on the leaky pipes, exposing them to further damage, such that the water will seep through the concrete slab foundation and into your home.

Key Takeaway

Slab leaks are dangerous because slabs serve as the foundation of the house. If this part begins to leak, the entire house could eventually come tumbling down. It is thus important that you address any signs of slab leakage to ensure that your home remains standing.

There are many factors that can cause a slab to leak. The age of the house, however, can be a prime reason since this could also mean that the water pipes are also deteriorating. To find out the exact cause of the leak, it’s always best to refer it to a reputable plumbing company.

Let Absolute Electrical Heating and Air Tell You How to Fix a Slab Leak

If you find your flooring wet most of the time, the problem could be due to a leak in your home’s concrete foundation. Absolute Electrical Heating and Air can make a quick diagnosis and determine if you have a leaking slab.

We offer a full range of plumbing services, including effective slab leak detection techniques. Call our plumber in Colorado Springs now to find out how we can help you.


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