Why the Right Contractor Matters for Pipe Relining

Pipe relining—often performed with cured-in-place pipe (CIPP) technology—has revolutionized drain repair by eliminating the need for invasive excavation. But the success of a relining project rests almost entirely on the skill and integrity of the contractor you hire. A poorly installed liner can delaminate, develop leaks, or fail within a few years, wasting thousands of dollars. Choosing a certified, experienced contractor is the single most important decision you will make for a long-lasting, trenchless repair. This guide expands on the core criteria to evaluate and provides the questions you need to ask before signing a contract.

Verify Certification and Licensing

Every reputable pipe relining contractor should hold both a valid general plumbing or specialty license (as required by your state or municipality) and industry-specific certifications. Licensing proves the contractor meets minimum competency and financial responsibility standards; certification demonstrates advanced training in trenchless repair methods.

Key Certifications to Look For

  • NASSCO PACP/LACP: The National Association of Sewer Service Companies offers the Pipeline Assessment Certification Program (PACP) and Lateral Assessment Certification (LACP). A contractor with PACP-certified technicians can conduct proper CCTV inspections before and after relining.
  • Manufacturer Certifications: Top resin and liner manufacturers (e.g., NuFlow, Perma-Liner, Wavin) provide training and certification for installers. Ask which brand the contractor uses and whether they are factory-trained for that system.
  • State Trade Licenses: In many states, pipe relining qualifies as plumbing or general contracting. Verify the license number online and ensure it is active and without recent complaints.

Do not accept vague promises. Request copies of certifications and license bonds. A trustworthy contractor will provide these documents without hesitation. Visit the NASSCO website for a directory of certified professionals in your area.

Assess Experience and Specialization

General plumbing experience does not automatically translate to pipe relining expertise. Pipe relining requires knowledge of resin chemistry, inversion versus pull-in-place methods, lateral reinstatement, and correct liner thickness calculations. Look for a contractor who has completed at least 50–100 relining jobs, and ask about the types of pipes they have relined.

Questions to Gauge Experience

  • How many pipe relining projects have you completed in the past year?
  • What pipe materials have you worked with (clay, cast iron, PVC, concrete, Orangeburg)?
  • Can you provide references from jobs similar to mine (residential lateral, commercial main, or storm drain)?
  • Do you have before-and-after CCTV video I can review?

An experienced contractor will freely share project examples and explain why certain resins or liner thicknesses were chosen. Avoid contractors who rely on vague answers like “we’ve done hundreds.” Ask for specific addresses of recent jobs (even if redacted) and talk directly to those homeowners.

Check Reviews and References

Online platforms like Google, Yelp, and the Better Business Bureau (BBB) offer a window into a contractor’s reliability, customer service, and workmanship quality. But go beyond star ratings: read the negative reviews to see how the company handled complaints. A consistent pattern of missed deadlines, poor communication, or failed liners is a serious red flag.

How to Verify Reputation

  • Ask for at least three references from projects completed within the last two years. Contact each reference and ask: Did the liner hold? Was the job completed on time? Were there any surprises?
  • Check the BBB rating for unresolved complaints or accreditation status.
  • Look for reviews on sites that focus on home services, such as Angi or HomeAdvisor. Note the volume of reviews—a few dozen positive reviews are more reliable than a handful.

Contractors with strong track records often have repeat customers or referrals from local plumbers. Conversely, if a contractor refuses to provide references or has a history of unaddressed complaints, move on.

Request Detailed Quotes

A pipe relining quote should be itemized to show exactly what you are paying for. Vague “lump sum” bids may hide cheap materials or unexpected add-ons later. Reliable contractors provide transparent estimates that break down all charges.

What a Quote Should Include

  • Materials: epoxy resin type, liner manufacturer, thickness (typically 3–6 mm for residential drains).
  • Labor: time for CCTV inspection, cleaning, resin mixing, inversion/installation, curing, and final inspection.
  • Mobilization: travel or equipment set-up fees.
  • Permits: if required by your municipality.
  • Warranty: length and what it covers (materials, workmanship, root intrusion).
  • Payment schedule: deposit (if any), milestone payments, final payment after inspection.

Be wary of quotes that are significantly lower than the competition. Cheap materials, insufficient curing time, or undertrained crews can lead to early failure. Get three to four quotes and compare not just the total price, but the scope and quality promised. Angi's guide offers a helpful overview of typical pricing.

Ensure Warranty and Guarantees

A strong warranty signals that the contractor stands behind their work. Reliable pipe relining contractors typically offer a 10- to 50-year warranty on materials and workmanship. However, read the fine print: some warranties exclude damage from tree roots, ground shifting, or improper maintenance.

Warranty Terms to Clarify

  • Is the warranty transferable if you sell the home?
  • Does it cover the full cost of relining the same section if the liner fails, or only the supply of a new liner?
  • Are there exclusions for certain pipe materials or chemicals (e.g., hot water, drain cleaners)?
  • Who covers the cost of re-digging if a liner fails and must be excavated?

Do not accept a verbal guarantee. Insist on a written warranty document that specifies duration, coverage, and the process for filing a claim. Contractors who hesitate to provide a written warranty likely lack confidence in their work.

Prioritize Safety and Compliance

Pipe relining involves handling epoxy resins, hot water or steam curing, and confined space entry. A responsible contractor follows Occupational Safety and Health Administration (OSHA) guidelines, obtains proper permits, and disposes of chemical waste according to environmental regulations.

Safety and Environmental Checks

  • Does the contractor have written safety protocols for handling resins and cleaning solvents?
  • Are their technicians trained in confined space entry and equipped with appropriate PPE (respirators, gloves, eye protection)?
  • Do they store and dispose of waste materials properly, including unused resin and chemical residue?
  • Do they pull permits for work that requires them (e.g., city sewer connections)?

Failure to follow safety rules can not only endanger workers but also contaminate your property or cause structural damage. The EPA provides guidelines for trenchless technologies that responsible contractors should follow.

Understand the Pipe Relining Process

Before you hire, take time to learn the basic steps of CIPP pipe relining. This knowledge helps you evaluate a contractor’s competency during the interview.

Core Steps of a Typical Relining

  1. Inspection: The contractor uses a high-definition CCTV camera to inspect the pipe interior, measure length, and identify obstructions, cracks, or collapsed sections.
  2. Preparation: Pipes are cleaned with high-pressure water jetting (or mechanical scraping) to remove debris, roots, and scale.
  3. Lining: A felt or fiberglass tube saturated with epoxy resin is inserted into the pipe—either by inversion (air or water pressure) or pull-in-place (winch).
  4. Curing: Hot water, steam, or UV light hardens the resin against the host pipe, forming a seamless, jointless, corrosion-resistant liner.
  5. Final Inspection: A final CCTV survey documents the finished liner, verifying no wrinkles, delamination, or blockages. Lateral cuts (connections to branch lines) are reinstated robotically if needed.

Understanding these steps allows you to ask informed questions: “How long will the curing process take?” or “What method do you use for lateral reinstatement?” A contractor who cannot clearly explain each step should raise concerns.

Equipment and Technology Matters

The quality of a relining job depends heavily on the equipment used. Advanced tools improve accuracy, reduce curing time, and detect hidden issues.

What to Look For

  • High-resolution CCTV cameras: The best systems pan, tilt, and zoom (PTZ) to capture detailed images. Standard definition may miss small cracks or root fibers that cause future leaks.
  • Robotic cutters: For reinstating lateral connections, robotic cutters are far more precise than manual methods, minimizing the risk of cutting into the liner.
  • Calibration tubes and liners: Contractors should use liners that match the exact diameter of your pipe. Poorly sized liners lead to wrinkles or failure.
  • State-of-the-art curing units: UV curing is faster and more energy-efficient than hot water, but requires expensive lamps. Ask which curing method they use and why.

Trenchless Technology magazine publishes reviews and comparisons of equipment that can help you understand the value of modern gear.

Red Flags and Warning Signs

Certain behaviors should immediately disqualify a contractor:

  • No written contract: Reputable contractors always provide a detailed, signed agreement that includes scope, timeline, payment schedule, and warranty terms.
  • Large upfront payments: Never pay more than 20–30% before work begins. Genuine contractors have enough capital to buy materials and pay crews.
  • Pressure to decide immediately: “This price is only good if you sign today” is a classic high-pressure tactic. Legitimate contractors give you time to compare quotes.
  • Uninsured or underinsured: Contractors must carry liability insurance (at least $1 million) and workers’ compensation. Ask for a certificate of insurance and verify its validity.
  • Refusal to show work examples: A contractor who cannot or will not share photos or references likely lacks experience or has poor results to hide.

If you encounter any of these red flags, walk away. The cost of fixing a failed relining job often exceeds the original savings.

How to Interview a Potential Contractor

A short phone call or on-site visit can reveal a lot. Prepare a list of 10–15 questions and take notes on the answers. Look for clarity, honesty, and willingness to educate rather than impress.

Top Questions to Ask

  1. What certifications do you hold, and can you send copies?
  2. How long have you been performing pipe relining specifically?
  3. What brand of liner and resin do you use, and why?
  4. Will you provide a written warranty, and what are its exact terms?
  5. Do you use a CCTV inspection before and after the job? Will I receive a copy of the final video?
  6. What is the estimated curing time for my job, and how long will the drain be out of service?
  7. Do you handle all necessary permits, or do I need to pull them?
  8. Can you provide three recent references I can call?
  9. What happens if the liner fails within the warranty period?
  10. Do you subcontract any part of the work? If so, who are they, and are they also certified?

The contractor’s answers should be direct and confident. If they hedge or offer irrelevant information, consider it a warning.

The Importance of Insurance

Pipe relining involves moderate risk: damaged water lines, accidental sewer backups, or worker injuries. A contractor without proper insurance can leave you liable for property damage or medical bills.

Insurance Types to Verify

  • General Liability Insurance: Covers damage to your property (e.g., if a water jetting operation breaks a window or floods a room). Minimum recommended coverage is $1 million per occurrence.
  • Workers’ Compensation Insurance: Required in most states for any business with employees. Without it, you could be responsible for medical expenses if a worker is injured on your property.
  • Umbrella or Excess Liability: Large contractors may carry additional coverage above the primary limits.

Ask for a certificate of insurance (COI) naming you as an additional insured for the duration of the project. Contact the insurance company to verify the policy is active. Never accept a verbal assurance or a photocopy that looks altered.

Conclusion: Making an Informed Choice

Selecting a certified and experienced pipe relining contractor requires thorough research, clear communication, and a willingness to compare options. Verify certifications and licensing, scrutinize experience through references and reviews, and demand detailed written quotes and warranties. Pay attention to safety protocols, equipment quality, and red flags. By investing time upfront, you ensure a durable, long-lasting repair that saves money and stress over the long term. Trust your plumbing to someone who earns it—through proven results, transparency, and a genuine commitment to quality workmanship.