# CIPP (DD-676) > 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. - Department: Tech - First published: 2025-12-05 - Last updated: 2025-12-05 - Permalink: https://detailenjoyer.com/case/cipp/ - Author: Marcus Easterling (DetailEnjoyer), The Detail Department ## On the timeline - **1971**: Eric Wood first uses cured-in-place pipe in London Full timeline: https://detailenjoyer.com/timeline/?case=cipp ## Quick facts - **DD-676-F01**: CIPP was first used in London in 1971. _(Write-up · Exhibit D (Track record))_ - **DD-676-F02**: Steam-cured CIPP sites can release chemical vapors such as styrene (Purdue, 2017). _(Write-up · Exhibit E (Emissions))_ ## Write-up A new pipe, no digging. Resin-soaked liners harden inside the old pipe. 1. **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. **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. **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. **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. **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. ## Related case files - [New York Hot Tub (DD-702)](https://detailenjoyer.com/case/new-york-hot-tub/): Another case involving city sewers - [Piston Pumps (DD-072)](https://detailenjoyer.com/case/piston-pumps/): Another case about industrial pipeline hardware - [Construction Covers (DD-631)](https://detailenjoyer.com/case/construction-covers/): Another low-disruption way to build in a city - [UV Curing (DD-640)](https://detailenjoyer.com/case/uv-curing/): UV light cures some pipe liners - [Hydrant Hygiene (DD-677)](https://detailenjoyer.com/case/hydrant-hygiene/): Another case about maintaining underground pipes - [Peristaltic Pumps (DD-689)](https://detailenjoyer.com/case/peristaltic-pumps/): Another case about tubes and pipes ## Reel vs. record - **Wording**: the standard term is 'cured-in-place pipe' (no hyphen before 'pipe'). The Reel's 'steam or, UV light' should read 'steam, or UV light'. - **Not quite seamless**: the liner is jointless, but side connections have to be reopened from inside after curing, usually with robotic cutters. - **Missing caveat**: curing can release chemical vapors. A 2017 Purdue-led study found styrene and other compounds in steam-curing plumes (ES&T Letters). - **Detail**: UV curing generally needs translucent glass-fiber liners. Felt liners are usually cured with hot water or steam. - **Missing history**: Eric Wood first used the method in London in 1971, and it was commercialized as Insituform. ## Video: CIPP: A New Pipe, No Digging - Duration: 26.4 s · Published: 2025-12-05 - File: https://detailenjoyer.com/assets/videos/DR5jw7WEsxG.mp4 ### Transcript 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! ## Questions & answers **Q: What does CIPP stand for?** A: 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)_ **Q: Where was CIPP first used in 1971?** A: 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)_ **Q: Which curing method generally needs glass-fiber liners?** A: 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)_ **Q: What chemical did the 2017 Purdue study detect at steam-cured sites?** A: 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)_ **Q: What reopens side connections after lining?** A: 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)_ ## Sources - [US EPA (2012): Retrospective Evaluation of Cured-in-Place Pipe (CIPP) Used in Municipal Gravity Sewers](https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P100DQFP.TXT) - [Teimouri Sendesi et al. (2017), Worksite chemical air emissions and worker exposure during CIPP installations, Environmental Science & Technology Letters](https://doi.org/10.1021/acs.estlett.7b00237) - [Wikipedia: Cured-in-place pipe](https://en.wikipedia.org/wiki/Cured-in-place_pipe) ## 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/