How to Fix a Slab Leak

If your home does not have a basement, it was built on a slab of concrete.  In many states, the plumbing codes require soft bendable copper piping under slabs because hard copper joints are not permitted.  Unfortunately, the construction process will leave these soft copper pipes with kinks and dents in them. Any ridge or kink in a pipe will tend to wear it down until it wears through.   The hot water pipes are usually the first to go because of the added stress of the expansion and contraction caused by the heating and cooling they are subjected to in the normal course of the day’s usage.  Add to that the hard water found in some areas, and you have a problem just waiting to happen.  Because ‘hard’ water is usually made up of calcium, lime and some iron, it is abrasive to the soft copper pipes. 

Some of the signs that you have a slab leak are;  moist or wet spots or stains on the flooring or carpeting, a warm spot on the floor, soggy or flooded landscaping, water coming through the foundation, a sudden settling of the foundation, low water pressure, or high water bills.  Leaks in the incoming water lines are continuous because there is a continuous water flow through these pipes.  If your foundation shifts, it will put extra pressure on your pipes and may even pull them apart.  Sometimes the diameter of your copper pipes is just too small for the volume of water that you need.  This will accelerate the corrosion of the copper pipes and help cause leaks to form where the pipes bend or change direction.  By the time you have realized that you have a leak, there is probably already extensive damage to the underlying pipes.  The ‘normal’ manner of repair involves using a leak detector to find the source of the leak to within three feet, taking everything off the top of that area – furniture, carpeting, flooring, etc.  Then you will use a jackhammer to get down to the leak, fix it, pour in replacement concrete, wait for it to dry and replace the flooring, the carpeting the furniture, etc.  Unfortunately, if one part of your piping has leaked, this means that the rest of it is probably not in the best of shape and will be likely to leak in the near future. 

            Now you have decisions to make regarding what to do with your slab leak.  Do you fix it with the jackhammer approach and hope that the rest of your plumbing will continue to work well?  Do you fix it with the jackhammer approach and use epoxy lining to restore the pipes that have had to be replaced and put epoxy-lining equipment on your existing fixtures and valves?  Do you fix it with the jackhammer approach and line the entire system with epoxy lining, or do you replace all the soft copper piping with aboveground hard copper piping that is guaranteed to last?  You will need to check your budget, check what is available in your area and what the cost of each approach is, and then decide what the best approach to solving your slab leak problem is.