Sewer Pipe Relining

What Is Sewer Pipe Relining And Why Is It Important

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Sewer pipe relining is an innovative trenchless method for repairing damaged underground sewer pipes without having to dig them up. As per relining experts The Relining Company, this process essentially creates a “pipe within a pipe” by installing a new pipe made of PVC or epoxy resin inside the old, failing one. Relining can restore aging sewer systems, prevent leaks, improve flow, and avoid costly full replacement.

Introduction to Sewer Pipe Relining

Sewer systems are essential infrastructure that most people rarely think about. Underground sewer pipes quietly carry wastewater away from our homes and businesses for treatment. However, over time pipes deteriorate from age, ground shifts, tree roots, corrosion, and more. Relining offers a minimally invasive sewer repair solution that restores function and longevity.

What is Sewer Pipe Relining?


Sewer pipe relining (also called CIPP) involves installing a tight-fitting structural liner inside an old pipe to essentially create a “new” pipe within the damaged one. Epoxy resins or PVC materials are used to form the new pipe layer that adheres to the old pipe walls.


Specialized relining contractors start by using CCTV cameras on robotic transports to thoroughly inspect and measure the pipes. Next, the old pipe is cleared of debris and prepared. A flexible felt tube saturated with wet epoxy resin is then inverted or pulled into the original pipe. It expands and hardens to form the relining layer.

Materials Used

Epoxy resins (for CIPP relining) or PVC in spiral-wound or fold-and-formed configurations are used. These provide structural integrity, chemical resistance, smoothness for flow, and longevity.

Why Reline Sewer Pipes?

Instead of trenches, jackhammers, and expensive full replacements, relining offers major advantages:

Extend Life of Sewer System

Relining can restore pipes to like-new condition with an additional 50+ years of life. It is perfect for pipes that are structurally intact but deteriorated.

Prevent Failures and Backups

By stopping leaks, restoring flow capacity, and providing corrosion resistance relining prevents major problems like backups, overflows, and collapses.

Reduce Excavation and Disruption

Because no digging is needed, relining reduces surface-level damage, business impacts, traffic issues, and safety hazards.

Cost Savings Over Replacement

Relining costs 50-70% less than full replacement by avoiding major excavation, new pipe purchase/installation, street repaving, etc.

Determining if Your Sewer Pipe Needs Relining

Several indicators help determine if epoxy or PVC relining is warranted for your aging sewer:

  • Signs of Deterioration
  • Slow drains
  • Gurgling sounds
  • Sewer gas odors
  • Inspections and Tests
  • CCTV camera findings like cracks, blockages, corrosion etc.
  • Dye flooding to check for leaks
  • Pressure testing for blockages
  • Identifying Issues

Professional assessments pinpoint specific areas, lengths and directions needing repair.

The Relining Process Step-by-Step

Cleaning and Preparation: First, specialized sewer jet cleaners thoroughly clean the old pipe. Technicians then make any repairs needed to ensure proper installation.

Video Inspection: CCTV cameras on crawlers record detailed footage for pre- and post-install analysis to verify results.

Installation: Depending on the system chosen, PVC pipes are blown in, inverted resin tubes fully expand and cured lamps speed epoxy hardening.

Curing and Finishing: Final CCTV inspections confirm correct curing and smooth finishes. The pipe ends are trimmed for manhole connections.

Types of Sewer Pipe Relining Systems

Cured-in-Place Pipe (CIPP): This “resin impregnated tube” relining is most common. Flexible felt tubes saturated with liquid epoxy are inverted then hardened with hot water, steam or UV light. It works for pipes from 3-36 inches wide.

Fold-and-Formed PVC: Pliable accordion-fold PVC comes compressed for insertion then expands using heat and pressure to fit irregular pipe shapes and mild curves.

Spiral Wound PVC: Rigid PVC strips are wound helically inside a host pipe with steel reinforcement included in larger diameters. Joints are thermally fused for leak tightness.


Sewer pipe relining provides a minimally invasive and long-lasting solution for restoring damaged pipes without excavations or property disruption. Investing in professional pipe relining keeps waste safely flowing while protecting the structural stability, environment, and health of both homes and commercial buildings over the long term.

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