Cured-in-place lining

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

"No-dig" is a description of surface disturbance, not a statement of quality. Lining is neither better nor worse than excavation in general; it depends on conditions that have to be established rather than assumed.

What this page cannot establish

SewerOwner cannot establish whether cured-in-place lining is appropriate for your property
this approach cannot establish that lining is appropriate for a given line without inspection
this approach cannot establish the condition of the ground around the host pipe
this approach cannot establish that the host pipe’s surroundings are unaffected
this approach cannot establish that this method is preferable to any other for a given property

What it attempts to do

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

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 the existing line can host a liner and the route allows installation
when surface disturbance along the route is a significant concern
when the affected length has been established by inspection

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 condition and configuration of the host pipe, from inspection
the length and any bends or transitions along it
whether any branch connections enter the lined section
access at each end
whether cleaning is needed first

Access and site considerations

requires access at one or both ends
requires the line to be prepared beforehand
reduces the internal dimension of the host pipe
branch connections within the lined length need specific treatment

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 lined length, stated as start and end points
what preparation is included, and whether cleaning is priced separately
how any branch connections in the lined section are handled
what conditions would make lining unsuitable once work begins
whether an inspection is performed after curing
what happens to the price if lining cannot proceed

What to keep afterwards

pre-work and post-work footage
the permit record where applicable
warranty terms as written
the record of what length was lined

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.

Sectional lining

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

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

Cannot establish: the condition of the line outside the placed length; that the identified condition was the only one present; that no further work will be needed.

Pipe bursting

Pulling a new pipe along the existing route while displacing the old one.

Replace the pipe along its existing route by drawing new pipe through while the existing pipe is displaced outward, using pits rather than a full-length trench.

Cannot establish: that the route is suitable without site-specific assessment; the position of other buried services; that this method is preferable to any other for a given property.

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.

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.

What would change the answer

the condition and configuration of the host pipe, from inspection
the length and any bends or transitions along it
whether any branch connections enter the lined section
access at each end
whether cleaning is needed first

What to do next

Lining depends on the host pipe cooperating, and the proposal should say what happens to the price if it does not.

Ask what happens if lining cannot proceed

If your situation is different

Only one length is affected: Sectional lining
You are comparing this against replacement: Pipe bursting

Change orders
Method-dependent contingencies belong in the written change-order process.