What Causes Slab Leaks?
Slab leaks occur when the pipes running in or under the concrete slab foundation of a home fail.
Leaks can occur in inbound pressurized fresh water lines, as well as outbound sewer or drain pipes. In this article, we will be primarily focusing on inbound fresh water piping located in or under slab foundations.
General causes of pipe leaks
There are several common causes of pipe leaks that can occur anywhere in a home's plumbing system; including in walls, attics, or in slabs. If they occur in or under a concrete foundation slab, they can be more difficult to detect and repair than leaks in other parts of the house. These general pipe leak causes can be due to:
Old copper pipes, corroded galvanized plumbing, and defective polybutylene piping can be prone to developing leaks under or in a slab.
If the water lines and fittings were not installed properly, they may be more prone to developing leaks over time.
High water pressure
Water pressure that is too high can put too much stress on the water lines and cause them to burst or leak.
Abrasion from pipes rubbing against other surfaces such as a concrete slab or other pipes, can cause them to eventually fail and leak.
The added chemicals (like chlorine) and PH of your water supply can interact with your plumbing and increase the likelihood of leaks. Copper pinhole leaks and polybutylene leaks have often been attributed to water chemistry issues.
Pipe leak causes unique to concrete slabs
In addition to the general causes listed above, some plumbing leaks occur due to reasons unique to their installation within or under a slab; primarily associated with ground movement.
Shifting or Settling Soil Causing Slab Leaks
Expansive or swelling soils are a common cause of pipe leaks in or under slabs.
According to the Colorado Geological Survey, it is estimated that expansive soil causes infrastructure losses in excess of tornadoes, floods, earthquakes, and hurricanes combined..
The American Society of Civil Engineers estimates that approximately 25% of all homes in America experience some form of damage due to expansive soil at some point in a home's lifetime.
There are two common causes of soil expansion and settling:
- Expansive clay soils: when clay soil experiences changes in moisture content, it will swell or shrink.
- Pockets of subsurface organic matter: it is common that pockets of trapped organic matter below the surface can oxidize or be compacted - resulting in surface soil settling.
Clay soils are common throughout the USA, with particularly high rates in Texas, Oklahoma, and parts of California. Sections of Florida are known have high levels of smectite clay (the most expansive type of clay), and also high levels of subsurface organic matter in the remains of prior wetlands.
Earthquakes Causing Slab Leaks
In earthquake prone regions like California, Nevada, Washington, and even Utah; earthquakes have had a significant impact on infrastructure, and have caused slab leaks. Any movement in the ground can cause cracks and movement in a concrete slab - which in turn can damage plumbing, causing leaks.
How to Prevent a Slab Leak
Other than not having a slab foundation in the first place, the only way to prevent a slab leak is to avoid having fresh water lines located in or underneath a concrete slab.
Our full home repiping service does just that. We cap off the fresh water lines that are already in or under your slab, leaving them in place. We then route all your new plumbing through walls, ceilings, and attics, avoiding the slab and preventing future slab leaks.
Our whole home repipes will also generally be much less disruptive than jackhammering open your slab to access and replace leaking pipes. With our One-Stop Repipe™ Process, we can complete a repipe of your entire home in just 1-2 days, and handle everything from inspections to wall patching- all backed by a lifetime warranty.
Slab Leaks: How Much Do They Cost to Fix?
The cost of fixing slab leaks by opening up a slab and replacing damaged pipes can vary significantly.
Here at Repipe Specialists, we only perform full home repipes.
We have heard from customers that in some cases, the cost of our whole home repiping services was lower than the cost of replacing a section of damaged pipe within a slab. This is particularly true for homeowners who've performed multiple in-slab repairs over time.
We consider an "in-slab" repair to be a temporary fix when compared to full home repiping. Whatever caused the original leak is unlikely to be a one-time event.
Most of our full home repipes cost between $4,500 for smaller homes and $15,000 for larger properties with more complex requirements and longer pipe runs. We have another article that covers whole house repipe costs in greater detail. We also offer financing options to help you manage any unplanned repiping costs.
Get the peace of mind that comes from never having to worry about slab leaks again: contact us to receive a free fixed price repipe quote from one of our local estimators.