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SLAB LEAK REPAIR
SLAB LEAK DETECTION
Advanced Foundation Repair has trained its estimators to use data collected during a foundation evaluation to help spot slab leaks. In addition, Advanced has its own full service plumbing affiliate. This is important for two reasons. First, we can help identify and locate leaks which may mean that foundation repairs are not needed. Second, it means that once foundation repairs are completed, we can rapidly respond to any plumbing issues caused by foundation repairs.
HOW DO I KNOW IF I HAVE A LEAK
Under slab leaks generally come in two forms, sewer leaks and leaks in water lines. If your water lines are leaking, you usually find out as soon as you get you get your water bill. Even a pin hole in a water line can leak out over 10,000 gallons in one month. In contrast, sewers can leak for years without anybody knowing. Unless a sewer is in expansive soils and a leak is adding enough water to swell the soils, there may be no signs of the leak.
When a water line or a sewer line leaks enough water into expansive soils, the soils can actually swell up and lift a building. This is called heaving. Often when a leak is causing heaving, the presence of the leak may be suggested by the way the overlying slab is being bent. Domes in slabs often indicate the presence of leaks.
Of course, once a foundation begins to move, all sorts of cosmetic damage can appear. In some cases, the damage can indicate the presence of a leak under the foundation. The shape and location of the damage can be a good indicator.
At Advanced Foundation Repair, all of our estimators are trained to prepare contour diagrams, which helps them to spot slab deformations that are typical of plumbing leaks. Estimators are also trained to correlate foundation damage with slab deformations, which helps to get an even better fix on slab leaks.
HOW DOES ADVANCED TEST FOR A LEAK
For water lines, there is a simple two step test. First a pressure gauge is attached to a spigot and the spigot is opened. As long as all water use is stopped, the gauge will show the pressure at which water is delivered from the street. Next, the water meter is turned off. If there are no leaks, the pressure on the gauge will remain constant. If the pressure falls, it means that water is escaping from the lines in and under the house. Generally, if a pressure drop is found, taps, toilets, and other water outlets are rechecked for drips or slow use. If no drips or slow use, such a running toilet, is found, then the lines must be leaking under the house.
For sewers, there is also simple two step test. First, the sewer line is blocked off with a balloon where it comes out from under the foundation. Next the sewer is filled with water. Given that the sewer is blocked off from the main, if the water level in the sewer drops, there must be a leak. Generally, when a leak is detected, the balloon is reset and the lines are retested.
Sometimes the test for a sewer leak gives a false reading, which is why the test should be repeated before going on to leak location.
Leak tests only tell you if there is a leak, they do not tell you where the leak is located.
HOW DOES ADVANCED LOCATE LEAKS
Sewer leaks are located with cameras that can be pushed down sewer lines, or by isolating and flooding individual sections of pipe. Water line leaks are usually located with listening devices of various sorts.
WHAT DOES IT COST TO FIX A SEWER LEAK
Repairing sewer leaks can cost from as little as $800 to over $20,000. The cost depends on the condition of the lines and the nature of the problem. If your home has old iron lines that have largely rusted away, then a major repair may be necessary. The only way to find out  is to have a camera inspection of the lines, which should include the use of a locating device, which helps to map the locations of the sewer lines.
WHAT DOES IT COST TO FIX A LEAKING WATER LINE
To repair a leaking water line, it is necessary to break though the foundation, cut out the damaged pipe, and then install new pipe. Such repairs are much simpler that sewer leak repairs and can often be fixed for less than $1,000. | 
