Trenchless Sewer Repair Explained

What is “trenchless sewer repair”?

“Trenchless” sewer repair is a minimally-invasive technique to repair damaged drainage pipes without the major excavation normally associated with sewer repair. The “trenchless” term refers to doing underground construction work without extensive digging.

The main benefit of trenchless sewer repair is that it can be performed without having to re-route traffic or dig a trench through your house. It’s faster than conventional methods and can usually be performed in hours rather than days. The faster service, combined with the costs saved from not having to reconstruct damage to the house, often makes trenchless sewer repair a less expensive alternative to traditional repair methods. Trenchless methods often require only one or two small pits outside the house, just enough to access the pipe.

The four most common types of trenchless sewer repair are:

· Cured-in-place-pipe lining (aka CIPP or structural pipe lining) involves creating a new pipe within the old one by inserting an epoxy-soaked liner into the damaged pipe and leaving it to cure for a few hours to make the pipe as good as new.

· Spray lining and brush coating is a technique similar to structural pipe lining, but instead of using a felt liner to create a new inner pipe, an epoxy or flexible polymer is sprayed or brushed onto the inside of the damaged pipe.

· Pipe bursting is used to replace a damaged pipe by using a winch with an attached bursting head to pull a new HDPE pipe into the old pipe. The old pipe breaks, and the new one takes its place.

· Slip lining involves inserting a smaller diameter pipe into the damaged one and then filling the area around it with grout. Slip lining dates back to the 1940s, and although it’s considered a trenchless technique, it’s more invasive because a larger pit must be excavated to lower the new inner replacement pipe sections.

Trenchless repair techniques are just as effective as traditional methods. In fact, the HDPE replacement pipes used in pipe bursting have a 50-100 year life expectancy. However, these methods don’t work in all cases.

The suitability of trenchless repair depends largely on the condition of the damaged pipe. If the pipe is collapsed, back-pitched, or improperly graded, trenchless methods might not work. Or, if the damaged pipe is easy to access, then traditional repair techniques might be more cost-effective. Contact a qualified sewer replacement contractor to determine if trenchless sewer repair will work for your home’s specific problem.

Interested in seeing step-by-step photos that explain the trenchless pipe lining method? Jump over to the PlumCore website of Birmingham, Al, and take a look at the process.