← Back to the archive★ Support my pages
DD-676TechFiled Last updated

CIPP

Short answer: Cured-in-place pipe (CIPP) is a trenchless way to rehabilitate sewer, storm, water and other pipes. A flexible tube of felt or fiberglass is soaked in thermosetting resin (polyester, vinyl ester or epoxy).

It's either inverted into the host pipe with water or air pressure, or pulled in and inflated. The resin is then cured with hot water, steam or, for glass-fiber liners, UV light. The result is a jointless pipe-within-a-pipe, usually a few millimeters to a few centimeters thick. Engineer Eric Wood first used the method in London in 1971, and it was commercialized as Insituform. A 2012 US EPA retrospective found sampled municipal sewer liners generally in good condition after years in service. Researchers at Purdue (2017) reported that steam-cured installations release a mix of chemical vapors, including styrene, which raised worker- and public-exposure concerns. Service connections have to be reopened from inside, usually by robotic cutters.

VideoWrite-up3 sources

In collections:Engineering Oddities

More like this★ Support my pagesCite this file

What should you know about CIPP?

Quick facts. Each one stands alone and has a stable ID you can cite.

  1. CIPP was first used in London in 1971.

    DD-676-F01 · Write-up · Exhibit D (Track record)

  2. Steam-cured CIPP sites can release chemical vapors such as styrene (Purdue, 2017).

    DD-676-F02 · Write-up · Exhibit E (Emissions)

Video transcript: CIPP: A New Pipe, No Digging

DID YOU KNOW? Cured-in-place-pipe, or CIPP lining, is a trenchless method used to repair damaged or aging pipelines without the need for extensive excavation. The process involves inserting a flexible liner saturated with a thermosetting resin into the existing pipe, and then expanding it using air or water pressure so that it conforms to the pipe's interior walls. Once in place, the resin is cured using hot water, steam or, UV light, hardening the liner into a durable, seamless new pipe inside the old one. NOW YOU KNOW!

Burned-in captions, read frame by frame (see transcript.md) · 26.4s Reel ·

Video coming soonCIPP · Instagram Reel
CIPP: A New Pipe, No Digging Instagram Reel · · 26.4s

The write-up

A new pipe, no digging. Resin-soaked liners harden inside the old pipe.

  1. Exhibit A

    The idea

    Instead of digging up a failing pipe, crews line it from inside through existing manholes or access pits. The liner becomes a new structural or semi-structural pipe.

  2. Exhibit B

    The liner

    A felt or fiberglass tube is impregnated with thermosetting resin and inserted by inversion (turned inside out by water or air pressure) or pulled in and inflated so it presses against the host pipe.

  3. Exhibit C

    Curing

    Hot water, steam, or UV light (used with translucent glass-fiber liners) cures the resin into a hard, jointless pipe. Robotic cutters then reopen the side connections.

  4. Exhibit D

    Track record

    First used by Eric Wood in London in 1971 and later commercialized as Insituform, CIPP is now one of the most widely used sewer rehabilitation methods. The EPA's 2012 retrospective found sampled liners generally performing well.

  5. Exhibit E

    Emissions

    A 2017 Purdue-led study measured chemical plumes, including styrene, at steam-cured worksites and called for more research on worker and public exposure.

Questions people ask about CIPP

What does CIPP stand for?

Cured-in-place pipe.

Source: Write-up · Exhibit A (The idea) · US EPA (2012): Retrospective Evaluation of Cured-in-Place Pipe (CIPP) Used in Municipal Gravity Sewers; Wikipedia: Cured-in-place pipe

Where was CIPP first used in 1971?

London, by Eric Wood.

Source: Write-up · Exhibit D (Track record) · Wikipedia: Cured-in-place pipe; US EPA (2012): Retrospective Evaluation of Cured-in-Place Pipe (CIPP) Used in Municipal Gravity Sewers

Which curing method generally needs glass-fiber liners?

UV light needs translucent liners.

Source: Write-up · Exhibit C (Curing) · Wikipedia: Cured-in-place pipe; Teimouri Sendesi et al. (2017), Worksite chemical air emissions and worker exposure during CIPP installations, Environmental Science & Technology Letters

What chemical did the 2017 Purdue study detect at steam-cured sites?

Styrene and other compounds.

Source: Write-up · Exhibit E (Emissions) · Teimouri Sendesi et al. (2017), Worksite chemical air emissions and worker exposure during CIPP installations, Environmental Science & Technology Letters

What reopens side connections after lining?

Robotic cutters working inside the pipe.

Source: Write-up · Exhibit C (Curing) · Wikipedia: Cured-in-place pipe; Teimouri Sendesi et al. (2017), Worksite chemical air emissions and worker exposure during CIPP installations, Environmental Science & Technology Letters

Test Your Knowledge

All quizzes →

5 questions, all from this case file. Answers are revealed instantly.

  1. What does CIPP stand for?

    1. Cured-in-place pipe
    2. Concrete-insulated plastic pipe
    3. Cast-iron pressure pipe
    4. Coated industrial polymer pipe
    Show the answer

    Answer: A. Cured-in-place pipe Cured-in-place pipe. Source: Write-up · Exhibit A (The idea) · US EPA (2012): Retrospective Evaluation of Cured-in-Place Pipe (CIPP) Used in Municipal Gravity Sewers; Wikipedia: Cured-in-place pipe

  2. Where was CIPP first used in 1971?

    1. London
    2. New York
    3. Tokyo
    4. Berlin
    Show the answer

    Answer: A. London London, by Eric Wood. Source: Write-up · Exhibit D (Track record) · Wikipedia: Cured-in-place pipe; US EPA (2012): Retrospective Evaluation of Cured-in-Place Pipe (CIPP) Used in Municipal Gravity Sewers

  3. Which curing method generally needs glass-fiber liners?

    1. UV light
    2. Hot water
    3. Steam
    4. Air drying
    Show the answer

    Answer: A. UV light UV light needs translucent liners. Source: Write-up · Exhibit C (Curing) · Wikipedia: Cured-in-place pipe; Teimouri Sendesi et al. (2017), Worksite chemical air emissions and worker exposure during CIPP installations, Environmental Science & Technology Letters

  4. What chemical did the 2017 Purdue study detect at steam-cured sites?

    1. Styrene
    2. Chlorine
    3. Ammonia
    4. Ozone
    Show the answer

    Answer: A. Styrene Styrene and other compounds. Source: Write-up · Exhibit E (Emissions) · Teimouri Sendesi et al. (2017), Worksite chemical air emissions and worker exposure during CIPP installations, Environmental Science & Technology Letters

  5. What reopens side connections after lining?

    1. Robotic cutters
    2. Explosives
    3. Excavators
    4. Divers
    Show the answer

    Answer: A. Robotic cutters Robotic cutters working inside the pipe. Source: Write-up · Exhibit C (Curing) · Wikipedia: Cured-in-place pipe; Teimouri Sendesi et al. (2017), Worksite chemical air emissions and worker exposure during CIPP installations, Environmental Science & Technology Letters

Cite this case file

Easterling, Marcus. "CIPP." The Detail Department (DetailEnjoyer), case file DD-676, last updated Dec 5, 2025. https://detailenjoyer.com/case/cipp/

Permalink: https://detailenjoyer.com/case/cipp/ · Last updated

Markdown version

Cite a single fact by its ID, for example DD-676-F01 → https://detailenjoyer.com/case/cipp/#DD-676-F01

Collection · Engineering Oddities Case file 12 of 29

Next in Collection · DD-689Peristaltic Pumps →