Choosing a lining contractor: six questions and three documents

A finished liner is a smooth bore you will never see again. Everything that determines whether it lasts happened before the video was recorded, which means the way to judge a contractor is to ask about the parts you cannot inspect, which is to say the six stages of a lining job.

The six questions

1. Will I get the pre-cleaning and post-cleaning surveys, not just the final one? The post-cleaning survey is the evidence that the liner bonded to pipe rather than to debris, and what a camera survey finds is the whole of that evidence. Almost nobody offers it unasked.
2. What is the liner thickness, and on what calculation? Diameter, depth of cover, loading, and whether the host pipe is assumed to be structural. This is a calculation, not a product choice.
3. How will the cure be controlled and recorded? Method, target profile, and the record you will receive. An under-cured liner is invisible on video.
4. How many laterals are on this run, and at what distances? If they cannot answer from the survey, the survey was not read properly, and a missed lateral is the most common serious failure in this work.
5. Who does the work: employees or subcontractors, and which crew? Not a trick question. The answer just needs to be a fact rather than a reassurance.
6. What is excluded? Bypass pumping, surface reinstatement, permit fees, excavation of an access pit, disposal. This question finds the difference between two quotes more reliably than any other, because what should be included is the five lines every lining quote has.

The three documents you should end up holding

• The pre-lining survey, including the lateral schedule with distances.
• The cure record.
• The post-installation survey of the finished liner.

Those three are the asset. If a property is sold in five years, they are what a buyer’s surveyor will want, and a warranty certificate without them is a piece of paper from a company that may not exist.

On warranties, briefly

A long warranty from a contractor is worth exactly as much as the contractor’s continued existence and willingness to honour it. A materials warranty from a resin manufacturer generally covers the material rather than the installation, and installation is where things go wrong.

None of that makes warranties worthless. It makes them the fourth thing to check rather than the first.

Licensing, which is not optional

Work on sanitary drainage is licensed plumbing work in most states, and work in the public right of way usually requires a separate contractor registration. Ask for the numbers, and check them against the state board rather than against a badge on a website. Ours are on the about page.