By Jared McCaskill, President — Nova Lining Company, LLC | June 2026
If you’ve been around the trenchless rehabilitation industry long enough, you’ve heard the war stories. A liner that wrinkled at a joint because a grease deposit was missed. A bypass pumping job that went sideways because the line wasn’t adequately flushed before installation. A client who paid twice — once for a CIPP liner, and once again to dig up the section and do it right — because the prep work wasn’t taken seriously the first time.
I’ve been doing this long enough to know: the liner is only as good as the pipe you install it into. Cleaning is not a line item you negotiate away to sharpen a bid. It is the foundation of every successful CIPP rehabilitation we do at Nova Lining.
In this post, I want to walk through exactly why proper pre-installation cleaning matters for small-diameter pipe — the 4", 6", and 8" laterals and mains that make up the majority of residential and commercial work in the DMV — and explain our process for getting it right every time.
"The liner is only as good as the pipe you install it into. Cleaning is not a line item you negotiate away. It is the foundation of every successful CIPP rehabilitation we do."
Why Cleaning Is Non-Negotiable for Small-Diameter CIPP
CIPP — Cured-In-Place Pipe lining — works by inserting a resin-saturated felt tube into a deteriorated pipe and curing it in place to form a seamless structural liner. When it works well, it’s one of the most elegant rehabilitation solutions the industry has ever developed. When it fails, cleaning — or the lack of it — is usually the culprit.
Here’s what most people don’t think about: in a small-diameter pipe, there is very little room for error. In a 48" culvert, you can have some residual debris and the liner will still find its shape. In a 4" or 6" lateral, a calcium deposit the size of a golf ball, a root mass that wasn’t fully cleared, or a grease buildup at a belly can mean the liner folds, bridges, or fails to fully seat against the pipe wall. That creates voids — and voids mean water infiltration, structural weakness, and a callback that no contractor wants.
Beyond liner performance, there’s a structural concern that gets overlooked: brittle pipe. A significant percentage of the small-diameter pipe we rehabilitate in the DMV is old — clay tile from the 1940s through 1960s, Orangeburg that’s been softening for 50 years, and deteriorated cast iron that’s been corrosively attacked from the inside out. These pipes are fragile. The wrong cleaning method — too much pressure, the wrong nozzle, a chain flail cutting through a structurally compromised section — can turn a candidate for CIPP lining into a candidate for emergency excavation.
"In a 4" or 6" lateral, a calcium deposit the size of a golf ball can mean the liner folds or fails to seat against the pipe wall. Voids mean water infiltration, structural weakness, and a callback that no contractor wants."
The Nova Lining Pre-Installation Process
At Nova Lining, we treat cleaning as a multi-step protocol, not a single task. Here’s how we approach it:
Step 1: CCTV Inspection Before a Single Drop of Water Hits the Pipe
We don’t start cleaning blind. Every project begins with a pre-cleaning CCTV inspection using a calibrated pan-and-tilt camera. We’re doing a PACP (Pipeline Assessment and Certification Program) coded assessment — not just a look-see. We’re documenting:
- Root intrusion locations and severity
- Grease and debris accumulation
- Structural defects (cracks, fractures, joint separations, deformations)
- Pipe material and condition to assess fragility before we select cleaning method and pressure
This step tells us what we’re walking into. It dictates whether we start with light jetting or need to sequence milling first. It tells us if we’re dealing with a pipe that needs to be treated with a light touch rather than full high-pressure attack. Skipping this inspection and going straight to a hydro jet at 4,000 PSI on a 70-year-old clay tile line is how you turn a lining job into a dig.
Step 2: Mechanical Root Cutting and Milling When Required
Root intrusion is one of the most common defects we find in small-diameter residential laterals in the DMV. Roots infiltrate through joint gaps, cracks, and deteriorated sections. A hydro jet alone is not sufficient to address a moderate-to-heavy root intrusion. Water pressure will blast away fine root tendrils, but it doesn’t address root masses at joints or established root plugs.
When our CCTV inspection identifies root intrusion, we deploy a mechanical root cutter — a high-speed rotary cutting tool matched to the pipe diameter — to remove root material before jetting. We never skip this step because if roots are compressed against the pipe wall and then a liner is installed over them, those roots continue to grow. Over time, they exert pressure against the liner, cause deformation, and can compromise the rehabilitation entirely.
For calcium and mineral encrustation — common in older cast iron and galvanized pipe — we use chain flails or purpose-built descaling tools. We match the flail weight and speed to the pipe condition. On fragile or heavily deteriorated pipe, we use lighter tooling and make multiple passes rather than one aggressive pass that risks fracture.
Step 3: Hydro Jetting — The Right Nozzle, the Right Pressure, the Right Technique
Once mechanical prep is complete, we move to high-pressure water jetting. This is where most of the cleaning work gets done — grease, sediment, loose debris, residual root matter, scale — but it’s also where the most damage can be done to brittle pipe if it’s executed carelessly.
Our operators are trained to adjust jetting pressure based on pipe condition, not just pipe diameter. We use rotating nozzles for general cleaning and penetrating nozzles for grease-heavy sections. On structurally compromised pipe, we reduce pressure and increase pass count rather than force a single high-pressure pass through a defective section.
We also pay attention to what’s coming out of the pipe during jetting. A sudden change in debris type — a shift from grease to soil, or the appearance of sand and aggregate — can indicate a fracture or a void in the pipe wall. We stop, re-camera, and assess before continuing. That discipline has saved us from several situations where an aggressive contractor would have continued jetting and collapsed a section.
Step 4: Post-Cleaning CCTV Verification — No Exceptions
After cleaning, we run CCTV again. This is non-negotiable. The post-cleaning inspection:
- Confirms that the pipe interior is clear and ready to accept the liner
- Verifies that the cleaning process did not cause or expose additional structural defects
- Identifies any remaining obstacles that need to be addressed before liner installation
- Provides a documented baseline that protects both us and the client
If the post-cleaning camera pass reveals a pipe that isn’t ready — a remaining root plug, a collapsed section that was obscured by debris, a joint that opened up during jetting — we know it before the liner goes in. This is exactly the kind of discovery that saves a project from failure.
The Risk of Wrong Cleaning Methods on Brittle Pipe
I want to be direct about this because it’s something the industry doesn’t talk about enough: aggressive cleaning methods on the wrong pipe can cause catastrophic damage, and that damage is the contractor’s liability.
The pipes at highest risk are:
Orangeburg pipe — bituminized fiber pipe installed primarily between the 1940s and 1970s. It absorbs water, softens, and deforms. High-pressure jetting can blow through Orangeburg walls or cause a collapsed section.
Severely deteriorated clay tile — clay is inherently brittle, and old clay laterals with multiple joint separations or longitudinal cracking will not tolerate aggressive mechanical cutting or high-pressure jetting without risk of collapse.
Thin-wall cast iron with heavy tuberculation — the corrosive pitting on the pipe wall can extend through the pipe wall in severe cases. Mechanical flails on heavily tuberculated cast iron can punch through weakened sections.
Asbestos cement (AC) pipe — we treat AC pipe with extreme care due to the fiber release risk when pipe walls are breached or disturbed by aggressive cleaning tools.
We’ve been called in on projects where a previous contractor ran aggressive cleaning on fragile pipe without first camera-inspecting the line, and the result was a collapsed section — turning what should have been a no-dig CIPP liner into an emergency excavation. The pipe that should have been rehabilitated had to be replaced. The homeowner paid for it. The contractor’s reputation absorbed it.
Our process specifically protects against this. When we identify fragile or severely deteriorated pipe during our pre-cleaning CCTV, we adapt. We use lighter tooling. We use lower pressures. We make more passes. We re-camera between passes. If we determine that a section is too compromised for cleaning without risk of further damage, we communicate that to the client before proceeding — not after we’ve caused a collapse.
"When we identify fragile or severely deteriorated pipe, we adapt. We use lighter tooling, lower pressures, more passes. If we determine a section is too compromised to clean safely, we tell the client before proceeding — not after we’ve caused a collapse."
What Proper Cleaning Means for the End Result
The payoff for doing all of this correctly is a liner installation that performs the way it’s supposed to — fully bonded to the host pipe wall, free of voids and wrinkles, with consistent resin saturation throughout the felt tube.
A well-cleaned and well-prepared pipe:
- Allows the liner to seat uniformly during inversion
- Means the curing process produces a smooth, tight bond with no air pockets
- Reduces the risk of post-installation wrinkles or folds at defect points
- Extends the functional service life of the rehabilitation — our LMK liners are designed and warranted for 50-year service life, and achieving that requires the prep work to match
We’ve also found that clients who walk away from a Nova Lining project with a clean pre- and post-installation CCTV video, a documented inspection report, and a liner that was installed into a properly prepared pipe don’t come back with problems. That’s the goal — not just doing a good job on installation day, but having the pipe perform correctly for the next five decades.
The Bottom Line
If you’re evaluating contractors for a CIPP lining project — residential lateral, commercial mainline, or anything in between — ask them about their cleaning process. Ask specifically:
- Do you CCTV before cleaning, or do you go straight to jetting?
- How do you handle root intrusion versus grease blockage — different tools, different approach?
- What pressure do you jet at on fragile or deteriorated pipe?
- Do you CCTV again after cleaning before the liner goes in?
- What’s your protocol if you find additional structural damage during cleaning?
If a contractor can’t answer those questions in detail, that’s a red flag. Cleaning isn’t a commodity — it’s a technical process that requires trained operators, the right equipment, and the judgment to adapt when conditions require it.
At Nova Lining, we’ve built our reputation in the DMV on doing this work the right way. That means investing in pre-project CCTV, deploying the right mechanical tools for the conditions, jetting with the right equipment by trained operators, verifying our work before the liner goes in, and never cutting corners because a bid needs to be sharpened. The pipe we’re rehabilitating will be in service for decades. The prep work deserves to match that standard.
Jared McCaskill is President of Nova Lining Company, LLC, a full-service trenchless pipe rehabilitation contractor headquartered in Springfield, VA. Nova Lining specializes in CIPP lining, manhole rehabilitation, CCTV inspection, cementitious and epoxy spray lining, Vac-A-Tee cleanout installation, and utility locating, serving residential, commercial, and government clients throughout the DMV and Mid-Atlantic region. Contact us at www.novalining.com.