Slab Leak Causes
There are several reasons that a water leak can develop in a slab foundation.
Slab leak causes:
- Settling or shifting slab: sometimes the slab itself shifts or cracks, causing plumbing to rupture and develop leaks. This could be due to expanding soils, soil erosion, earthquakes, etc.
- Copper pinhole leaks: copper piping can develop pinhole leaks over time. It may have been low quality and/or defective copper piping to start with, or had reactions to either the concrete it is encased in, or water chemicals.
- Pipe abrasion: particularly with copper piping used on hot water lines, any movement in the pipe (i.e. from temperature expansion) or slab over time, can eventually abrade the piping until it fails.
- Old plumbing: all plumbing systems have a limited life, and can eventually fail anywhere in a home. In older homes, a slab leak may not have anything to do with the slab itself - and simply be the result of plumbing reaching the end of its service life and needing replumbing.
A slab leak isn't always completely obvious, and can go undetected for extended periods of time. Homeowners with slab foundations should regularly check their slabs for tell-tale signs of a leak, as undetected slab leaks can cause serious problems, including; soil erosion & slab settling, mold in wall cavities or behind cabinets, flooring damage, or simply wasted water and an excessive water bill.
Signs of a slab leak:
- Warm areas: hot water line leaks will usually cause hot spots in a slab. Regularly walk barefoot around all areas of a slab, and see if warm spots are noticeable. Wood floors or carpeting may mask temperature differences however.
- Signs of mold: dampness can build up over time under carpets, below cabinets, near wall bases; all leading to potential mold growth. Check under rugs and carpets, in closets, under cabinets: basically any areas with limited ventilation on the ground floor that you can access.
- Excessive water use: pay attention to water usage patterns, looking for unexplained increases. You could also do a test by shutting off all water for a period of time, and then compare the before/after water meter readings (this method may not detect slow leaks).
If you suspect a water leak, but can't tell for certain - there are leak detection companies with specialized leak detection equipment. They can usually detect even very small, slow leaks. We generally recommend using a leak detection specialist, rather than a plumber. Most detection companies will charge a fee for their service - but have no conflicting incentive to "find" a leak, since they don't typically offer leak repair services.
Should I Repair or Repipe After a Slab Leak
This is an easy answer: if you've had a slab leak, repiping is almost always the more cost-effective solution.
We've actually had situations where our full repipe quotes were less than what customers had previously paid for temporary slab leak repair solutions. Repairing leaks in slabs can be expensive and intrusive, as it requires opening large (and often multiple) portions of a slab - and then relaying concrete, in the middle of your home interior.
We've also performed many repipes for homeowners who had no plumbing issues, but wanted to be proactive and avoid the headaches and costs their neighbors experienced with unplanned slab leaks.
A repipe does not require cutting in to the concrete slab. We instead re-route all the plumbing through walls, ceilings, and attics - bypassing the slab entirely. Not only is this more cost-effective than repairing pipe in a slab: you'll have the benefit of never having to worry about a slab leak again.
What Are My Repipe Options for Slab Leaks?
Most repipes are now done with either PEX tubing or copper piping (we offer lifetime warranties for copper repipes and PEX repipes). Read our article about PEX repiping: it is the most commonly chosen option by our customers here at Repipe Specialists.
Most of our repipes are priced between $4,500 for a smaller home, and up to $15,000 for larger more complex projects. Read more in How Much Should A Repipe Cost. We also offer repipe financing options to take the sting out of unplanned repipe expenses.
A Repipe Specialists local estimator would be happy to explain all your options, either in person or in a remote consult session - schedule a free repipe quote.