How To Fix a Slab Leak

Among the list of problems a homeowner can encounter, a slab leaks ranks high among the worst ones. Basically, a slab leak is one that occurs in the water pipes located under the foundation or in the concrete slab where the house rests. When this kind of leak occurs, lots of potential problems arise – can be severe water damage or humidity issues inside the house or other worse scenarios. This is why it’s very important to perform a slab repair in order to lessen the damages to your home. Otherwise, you will be paying a really hefty sum to get everything fixed.

A lot of homes were built on a concrete slab foundation which is a single layer of concrete that is several inches thick that rests on a bed of crushed gravel. What usually happens is that pressurized water pipes and sewer lines are installed underneath the foundation before pouring the concrete slab. Since these pipes can deteriorate as time passes (particularly copper piping in acidic soil), a slab leak is created.

Although slab leaks are hard to detect, there are some tell-tale signs that point to it being the problem. Among the signs include a sudden increase of the water bill, a very noticeable drop in water pressure, always hearing the sound of water running, finding the carpet or any other flooring to be damp, seeing foundation cracks or settling and spotting mildew in the wall or in the basement.

When you notice any one of the signs above, it’s best to find the slab leak and get it fixed as soon as possible. Why is it so important? For one, further damage can be very costly.

Even though slab leaks are difficult to detect, they are not so hard to repair. Then again, finding and getting access to it is a different story. So the first thing you should do is locate the area of the leak. After that, you will have to work your way through the concrete in order to repair the pipes.

Detecting a Slab Leak

A leaking pipe underneath your foundation can be either a water or sewer line. The biggest sign of a leak is seeing water or damp spots on the floor. In addition, hot water lines that are leaking create warm spots on the floor. You can try walking around barefoot in your home to find the location of a leaking hot water line.

Another sure sign of water lines leaking is hearing the sound of rushing water underneath the floor. Also, a good sign that there is a leak is seeing a really high water bill than what you are used to.

Sewer Line Leaks

It’s a whole different problem when a sewer line leaks. Why is that the case? For one, they can go undetected until visible signs appear indicating a damage to the foundation.

However, there are conditions when leaking sewer lines are easier to detect. For instance, in places with expansive soil, heaving (this is when a slab will swell enough to lift a building) occurs when there is a leaking sewer line. A dome or raised section on the floor is another good indication of a sewer line that is leaking.

Leaks That Are Hard To Find

Often times, slab leaks are hard to find. You will need to use specialized listening devices in order to find the leak. Air is pumped into lines in order to force the remaining water out after the water is turned off. After this is done, a plumber can then listen for escaping air from the damaged pipe. The best way to fix the issue can then be decided once the leak has been identified.

One of the most common fixes is to just re-plumb the entire house rather than just spend money on repairing plumbing that is rather old. This solution is recommended when a home uses old galvanized piping. These kinds of pipes are hard to fix and will continue to leak as they age therefore it’s best to consider re-plumbing.

Getting Access To Slab Leak

In order to fix a slab leak, you need to gain access to it. Doing so needs you to break a hole in the slab using a jackhammer. To expose the concrete slab, the finished flooring should be removed. There is an exception to this though: ceramic tile.

Keep in mind that a lot of dust is created when you open a slab. This is why it’s very important to cover all valuables and furniture before you attempt to expose the slab. Even better, if you have other storage options, it is best if you remove all your items there before doing repair work.

When the hole has been cut, removing dirt reveals the leaking pipes.

Repairing a Slab Leak Caused By Water Lines

Copper tubing is the most common kind of pipe used for water lines located underneath a slab foundation. When copper pipes age, they tend to wear thin and as such, are prone to leaking.

You will need to cut the damaged section of the pipe with a hacksaw in order to repair it. Other tools you can use are a reciprocating saw or tubing cutter. Once you have cut the damaged part, you have to remove it.

After doing all this, solder a new piece of tubing that is combined with copper couplings into place.

Repairing a Slab Leak Caused By Sewer Lines

Since dealing with sewer lines can be trickier, you might need the services of a plumber. One, sewer line issues are harder to detect and two, there are health issues involved when dealing with such lines (e.g. exposure to human waste). The kind of pipe you might have in your home also depends on the age of your property. So you can have cast iron, clay or PVC pipes.

Special rubber couplings can be used to fix the issue but they are not ideal for pipes located underneath concrete slabs. They might be good for connecting different kinds of pipes but they are not useful in this situation. In addition, the rubber boots can deteriorate as time passes, particularly when used outdoors.

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