SewerOwner

Sectional lining

Lining a defined length within the line rather than its full run.

What this page cannot establish

  • SewerOwner cannot establish whether sectional lining is appropriate for your property
  • this approach cannot establish the condition of the line outside the placed length
  • this approach cannot establish that the identified condition was the only one present
  • this approach cannot establish that no further work will be needed

What it attempts to do

Place a liner across one identified length, leaving the rest of the line as it is.

When contractors may discuss it

These are circumstances in which the approach comes up, not a checklist that makes it correct. There is no situation in which one method is universally right.

  • when a condition is confined to an identified length
  • when the rest of the line has been inspected and is being left in place
  • where access and configuration allow placement

What has to be known before applicability can be judged

If a proposal for this work is priced without these, it is priced against assumptions. That is not necessarily wrong — but the assumptions should be written down.

  • the location and extent of the condition
  • what is known about the rest of the line
  • whether branch connections fall within the length

Access and site considerations

  • requires an access point suitable for placement
  • placement accuracy depends on measurement from a stated reference

What to clarify in a proposal for this work

These are the details that most often differ between two proposals for what sounds like the same job.

  • the exact length and its start and end points
  • how placement position is verified
  • what happens if the condition extends beyond the sectional length
  • whether an inspection follows placement

What to keep afterwards

  • pre-work and post-work footage
  • the recorded position of the placed section
  • warranty terms as written

Alternatives worth asking about

Asking why one approach is proposed rather than another is a reasonable question, and the answer tells you what the contractor believes about your line.

Cured-in-place lining

Installing a liner inside the existing pipe that hardens in place.

Create a new pipe wall inside the existing line, using the existing pipe as the host, without excavating the full route.

Cannot establish: that lining is appropriate for a given line without inspection; the condition of the ground around the host pipe; that the host pipe’s surroundings are unaffected; that this method is preferable to any other for a given property.

Spot repair

Repairing a defined length of the line rather than the whole run.

Address a condition at one identified location, leaving the remainder of the line as it is.

Cannot establish: the condition of the rest of the line; that no further work will be needed; that the identified condition was the cause of a symptom.

Traditional excavation

Digging along the line to expose and replace pipe directly.

Expose the line so that pipe can be removed and replaced, and so that what is uncovered can be observed directly.

Cannot establish: the condition of any section outside the excavation; that no further conditions exist elsewhere; that the new installation will perform for any stated period.

What would change the answer

  • the location and extent of the condition
  • what is known about the rest of the line
  • whether branch connections fall within the length

What to do next

A sectional placement is only as good as the measurement it is placed against.

Check how the placement position is verified

If your situation is different

Related, and why