Preparing for lining

Lining installs a new pipe inside the existing one. Because it works through existing access points, the surface disruption is much smaller than an excavation — which is the whole appeal, and also the source of most of the misunderstandings.

A lining job has more preparation than a homeowner expects and less digging. Most of what can go wrong is decided before the day.

What this page cannot establish

SewerOwner cannot tell you what is wrong with your line, and nothing on this page is a diagnosis
the words a contractor uses have no agreed definitions in this trade, and two companies use them differently
no price, range, or cost driver on this site is a quotation, and none can be
nothing here establishes who is responsible for the length of pipe being described
SewerOwner cannot establish whether lining is suitable for your line
no lifespan or performance outcome is asserted for any lining product

What has to be true before lining is possible

the line has been cleaned, so the liner is going against pipe rather than debris
the existing pipe is intact enough to act as a host along the lined length
the line can be reached from existing access, or a new access point is in the scope
any branch connections along the length have been identified and there is a plan for them
the condition being addressed is one lining can address

What lining does not fix

It does not correct the shape of the ground under the pipe. A line with a genuine sag will still have that sag after lining, because the liner follows the host.

It also does not address a length that has separated far enough to lose its shape, and it does not reach beyond the access points it is worked from. If any of those describe your line, ask specifically how the proposal handles them.

Worth agreeing in writing beforehand

exactly which length is being lined, in distance from a stated access point
what happens to each branch connection along that length
whether any new access point will be created, and where
whether drainage is out of use during the work, and for how long
what the post-lining inspection will show, and that you receive a copy
what is warranted, for how long, and what voids it

What to ask

What did the pre-lining inspection show, and may I have it?
Which length exactly, measured from where?
What is the plan for the branch connections along it?
Will any digging be needed for access, and where?
Can we use water during the work, and for how long is it out?
What does the post-lining inspection have to show for this to be signed off?
What is not addressed by this work that we know about?

What would change the answer

the pre-lining inspection, showing the line was cleaned and is suitable
what the proposal states about access points and whether any will be created
what happens to any branch connections along the lined length
what the post-lining inspection will show and when you receive it

What to do next

What the method is trying to do is what determines whether the preparation makes sense.

Understand what lining attempts

If your situation is different

Only part of the run would be lined: Sectional lining
You are still comparing lining against digging: Repair or replace
You want to record the property first: Documenting before work

Project timeline
Where lining sits in the wider sequence.
Bellied line
The condition lining is least able to address.
What drives scope
No-dig avoids some cost drivers and not others.
Cleaning first
A line has to be cleaned before it can be lined or judged.
During the work
What to expect while the crew is on site.
After the work
What to keep once the work is finished.
Get help
A person reads it. It is not a contractor booking, and describing what you were told is often enough to work out which question is actually unanswered.