Sewer Pipe Lining (CIPP)

How cured-in-place lining works

A felt or fiberglass tube is saturated with resin, pulled or inverted into the cleaned host pipe, pressed against the wall with air or water, and cured with hot water, steam or UV light. When it hardens you have a new, jointless pipe inside the old one. The liner takes up a small amount of diameter, but its smooth wall flows better than corroded cast iron or offset clay. Lateral liners are typically rated for a 50-year service life.

What has to happen first

A camera inspection to map the line and every branch connection, hydro jetting to strip roots and scale so the resin bonds to clean pipe, and measurement so the liner is cut to length. After the cure, branch connections are reopened from inside with a robotic cutter and the line is filmed again.

When lining is the right fix

• Root intrusion at joints, longitudinal cracks, small offsets, pinholes or channeling in cast iron — on a pipe that is still round and holding grade.
• Lines under slabs, driveways, mature landscaping or streets, where the cost of a trench is mostly the cost of restoring what is above it.
• Coastal and high-water-table lots where an open trench means dewatering and shoring.

When it is not

Collapsed pipe, bellies that hold standing water, and lines that were undersized to begin with. A liner follows the host pipe's shape, so a bad shape stays bad. Those lines get pipe bursting or a spot replacement. Under-slab cast iron with several tight bends usually gets a spray-applied liner rather than felt.

Questions worth asking

What resin system and cure method will be used, what the liner's rated life is, whether the branch connections were counted, who pulls the permit, and whether you will receive the before-and-after video. A contractor who does this every week answers all five without hesitation.