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Proceed With Caution When Replacing Your Main Drain Line

Pipe being dug up in front of a house It may not be able to speak, but your home has ways of telling you when something is going wrong. Make sure to pay close attention to signs of damage to the main drain or sewer system in your home.

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The main drain is the sewer line that runs from the house and connects to the city sewer system. Residential lines typically are four inches in diameter and can vary in length anywhere from 15 to 100 feet. Houses built in the late 1970s to present day usually have PVC drain lines, but older homes may have cast iron or clay tile main drains.

These older systems can be problematic for a few reasons. First, the inside of the line can become rough over time, as scale can build up inside the pipe. Clay and cast iron piping were installed in sections, and as the ground settles or changes over time, these sections can move apart from each other resulting in an “offset tile.” Both offset tile and scale in the line can result in the drain clogging up, as paper and waste can become caught and form a blockage.

The other big problem with the main drains in older homes is the potential for tree roots to grow inside the line. Since the pipe was installed in sections, the roots will grow between the sections in search of water. The newer PVC pipe is smooth on the inside, and the joints are glued together, keeping the roots out.

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Due to age and/or root damage, the older clay and cast iron drain pipes eventually can collapse. When this happens, you may need to have the line replaced, which can be a costly proposition. The average cost to repair a sewer main is $2,400, however, you could spend anywhere from $1,000 to $3,700, depending on the damage.

Drains are under the ground, and the problems are not always obvious to many homeowners, so having a company you trust to make sure the line truly needs to be replaced is always a good thing. Consumers should use caution and not be pressured on the spot into costly repairs. There are always dishonest people looking to take advantage of others, especially in a time of crisis and high emotion.

When asking how much it costs to repair the main sewer line, a homeowner should consider the cause and complexity of the project, all repair options, and related projects caused by the damage. The positive is that, if the line is installed properly when it is replaced, you should have to do it only once.

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