What is a slab leak and how does it look like? The Best Answer

A slab leak is a type of leak that occurs when the drains under your home’s concrete slab break and water begins to pour out. The wastewater can come up from your home’s drains, go into the ground, and contaminate the soil around your house. 

 A slab leak can also cause sewer gases to seep into your home, making you sick. Slab leaks are very expensive to fix and can cause extensive damage to your property’s foundation. But there are some preventative measures you can take to avoid such a disaster.

These include installing an alarm system that will alert you when it detects a change in water levels, checking for any cracks on the surface of your home’s concrete slab, replacing any outdated pipes or pipes with visible splits, and making sure that all plumbing is well-maintained. Here are some ways to prevent leaking in your house before it becomes a bigger problem!


How do slab leaks occur: causes explained?

There are multiple causes of a slab leak. These can include an earthquake, heavy storms, or extreme heat. It is also possible that rodents chew on your drains. Tree roots can also damage your drains. It is also possible that they got damaged when the slab was poured. The most common cause is that the drains get old and start to crack. 

Often slab leaks go unnoticed for a while as the plumbing systems still function. A bad smell or an inspection is often the way that people find out about it. Given that these inspections cost a lot of money and time, they are not often performed.

It is also possible to go in the drain with a camera to see what is going on but this might not catch all the issues. More recently people are starting to use sensors to detect problems. To be sure that there are no problems, you will have to do a water pressure test. This involves closing the drains with a rubber ball. Water is then pumped into the closed drains.

Then we wait for 15 minutes and see if the water pressure changes or not. If it changes, it can indicate that water is leaking away. Further inspection is at that point needed. We might have to dig under the foundation to see where the leak is located. Often it is where two drains are connected (at the joint) that we will see a leak as these are weaker points. 

You should inspect walls and slabs often to make sure that there are no wet spots or other problems.

Pipes with city water generally run above the slab in the house so they are easier to work on. Leaks are easier to detect as your water meter will spin faster and you will get a big invoice. Furthermore, you can often see wet spots on the wall.

It is possible that the pipes run under the floor but they generally won’t go under the slab. It is quite easy to fix this as you can reroute the waterpipe without having to dig. For this reason, leaky pipes are generally not considered slab leaks

If you notice that there is a wet spot on the floor, it can be a slab leak.

How to fix a slab leak: repair cost and more

If you’ve detected a leak in your home, it’s important to take the necessary steps to fix it. The first step is to locate where the leak is coming from. This can be a challenge as it can involve digging under the slab. It is possible to open up the floor but this can be messy. For this reason, some people opt for a tunnel under the slab. 

 Once you’ve determined where the leak is coming from, you can fix it. This is often done by cutting the drain open. Drains are generally made from PVC (although other materials such as PE or cast iron can be used as well). This is then cut open and a new piece of PVC is glued to the old parts. In some instances, it is possible that a big part of the drain needs to be replaced.

If the leak also has damaged the slab itself, it is possible that an engineer has to check how it needs to be repaired. The plumber, engineer, and contractor will have to coordinate the works in these instances. This is generally something that you should leave to the pros as slab leaks can be dangerous and lead to a lot of other issues such as tears in your walls or pollution. 

It can be impossible to sell a house that has a slab leak so be sure to find a good solution for the problem. This can require expensive repairs. The plumber can check what is possible. Often it is best to work with a plumber that is specialized in this type of repair as it requires special techniques and tools. 

Repairing a slab leak can cost anywhere from a few thousand to tens of thousands of dollars. Often this can be deducted though so homeowners don’t end up paying that much.

 How to avoid a slab leaks: how common are they?

It can be quite hard to avoid a slab leak completely. There are some things that you can do though. If your plumbing system is older than 10 years, you might consider it from time to time. This can include using a heat camera to see if there are wet spots. You can run a camera through your drain as well. Your plumber can do a pressure water test every 5 years.

This is quite expensive but can be worth it if you can detect leaks early on. Once your plumbing system is 20 years old, you can consider replacing it if it is showing wear and tear. Each installation and location is different but regular inspections make sure that you can see what is going on. 

You can also check with your neighbors. Houses have often been built during the same period. If they have problems, it is possible that you have to check your system as well. Sometimes whole areas have to replace their drains as they are reaching the end of their lifetime.

It is to be expected that regulators will become stricter and require inspections in the future. Wastewater can leak into groundwater and this can lead to a lot of problems. For this reason, we can predict that there will be more regulations around this in place in the future. Especially when a home is being sold, certifications will be needed to make sure that everything is clean. 

To conclude, we can state that slab leaks can be annoying and expensive. You should try to find them as soon as possible as they can damage your house and the earth around it. For this reason, it can be worth it to inspect it every few years. If you have a leak, make sure to work with a professional as these are often complex repairs that you can’t do on your own. 

We have discussed the structure of a slab here (including stem walls).