Cured-in-place pipe lining.

§ I · How it works

The host pipe is first cleaned by a combination of mechanical cutting (sectional auger, root saw) and high-pressure water jetting (typically 3,500 psi at 18 gpm). Roots, scale, and bituminous joint material are removed; the bore is verified clear by a second CCTV pass. The pipe is then dried with compressed air. A length of polyester or fiberglass felt tube — pre-saturated under vacuum at the shop with a thermosetting resin (we use either a styrene-free vinyl-ester, depending on the application, or a UV-cure GRP from Brawoliner when the sleeve has to negotiate a 90° bend at the foundation) — is inverted into the bore through the cleanout, turning inside-out as it goes so the resin-coated face ends up against the host pipe wall.

Once fully inverted to the termination point at the city main, the sleeve is pressurized to a working differential of 8–14 psi against the host pipe and held there for the duration of the cure. The cure time is the variable: ambient cure, 18–24 hours; hot-water cure (the most common method on residential laterals), 4–6 hours; UV cure (the fastest, most consistent, most expensive option), 30–80 minutes. The internal pressure prevents wrinkling and ensures the cured liner conforms tightly to the host bore — including across bell-and-spigot joints, lateral connections, and minor offsets up to about 10% of the nominal diameter.

After cure, the sleeve is cooled, the ends are trimmed flush, and any branch connections that were sealed off by the liner are reinstated by a robotic cutter (a remotely operated cutter on a tracked carriage that cuts a precise-diameter circular opening at the location of each lateral connection, indexed off the pre-install survey). The result is a continuous, jointless polymer-composite liner with a minimum thickness of 4.5 mm for a 4-in. pipe, 6.0 mm for a 6-in. pipe, sized per the ASTM F1216 design equations and the survey-day diameter measurement.

§ II · When it's the right answer

CIPP is the right answer when the host pipe is structurally compromised but bore-continuous. Specifically, when the survey shows any of the conditions in the Failure Atlas at the following severities:

• Root intrusion at any severity that doesn't physically prevent the inversion (we mechanically remove the roots first; the liner seals the joint they came in through).
• Longitudinal cracks of any length, provided the pipe is still circular in section.
• Joint offsets up to approximately 10% of the nominal diameter (i.e. ≤ 0.6 in. on a 6-in. pipe, ≤ 0.4 in. on a 4-in. pipe).
• Bell-and-spigot deterioration with leaking but intact joints.
• Hairline circumferential cracks at the spigot end, the most common pattern under heaved foundations.

§ III · When it isn't

CIPP is the wrong answer when:

• The pipe is collapsed in any section. There is nothing for the liner to take a shape from.
• Joint offsets exceed 15% of nominal diameter; the liner will not bridge them cleanly and you will get a wrinkle that traps solids.
• The lateral has a substantial belly > ½″/ft. The liner will harden in the dip and the dip will remain.
• The pipe is undersized for current household demand. CIPP reduces the inside diameter by 4–6 mm; if you're already at the limit, you can't afford to lose another quarter inch.
• The customer is selling the house in 90 days and the buyer's lender wants documentation of replacement, not rehabilitation. Some lenders will accept CIPP. Some won't. Ask first.

§ IV · The toolchain we use

Our inversion drum is a Perma-Liner Quik-Shot 50, mounted on a 16-foot trailer with the resin barrels and a propane-fired hot-water boiler for cure heat. The robotic cutter is an iPEK Rovion (Marie's spec; replaced an older Aries unit in 2022). The CCTV crawler is a CUES KP-380 with an LACP-compliant overlay. The hot-water boiler is a Reimers Electra-Steam, the only piece of equipment we own that pre-dates the founding of the shop.

§ V · Cost & warranty

The posted range for a 40–60 ft residential lateral lining, 4 to 6 in. ID, in our service area, is $5,800–$9,200. The variable is access — a clean, dry basement cleanout with a straight shot to the main is the low end; a flooded crawlspace with a 22.5° bend at the foundation entry is the high end. The price includes the BSA permit, the post-install CCTV verification video, NYS sales tax, and a 1-year workmanship warranty on our portion of the work. The cured liner itself carries a 10-year structural warranty from the resin manufacturer²; ASTM F1216's design life is 50 years.

§ VI · What we won't pretend

CIPP lining is not new. The first commercial installation was in London in 1971 by Insituform.³ The technology is mature, the failure modes are well-understood, and the chemistry has improved meaningfully since the 2010 EPA review⁴. There is real research, including from Purdue's 2017 study, on cure-time air-quality concerns; we use styrene-free chemistries on residential interior installs because of that work. We will hand you the manufacturer's safety data sheet on request and we'll wait while you read it.