What are the disadvantages of trenchless pipe replacement?

It Cannot Fix Grade

This is the most consequential limitation and the least advertised. A liner follows the host pipe. If a section has sagged into a belly that holds standing water, lining it produces a smooth, watertight, warranted pipe that still holds standing water in exactly the same place. The symptom that brought you to the problem — debris settling in the low spot and blocking — continues.

Pipe bursting is better here, since new pipe is drawn through on a winch line and can improve alignment, but it is not a regrading method either. Where the fall is genuinely wrong, open-cut replacement is the honest answer. Any quote to line a pipe with a known belly deserves a direct question about what happens to the belly, and the camera footage discussed in relining versus replacement is where that shows up.

The Other Limits Worth Knowing

• Diameter loss. A cured liner occupies several millimetres of wall thickness. On a correctly sized lateral this is immaterial; on one already undersized for the fixture count, it is not.
• Reinstated branches. Lining covers every branch connection, which then has to be reopened with a robotic cutter. Done well this is invisible; done poorly it leaves a lip that catches debris, or an incompletely opened connection.
• Access pits are still excavation. Two pits, reinstated afterwards. Trenchless is quieter and narrower, not surgical.
• Host pipe condition governs. Collapse, severe offsets and deformed Orangeburg all rule lining out, so a method chosen before scoping can fall through late.
• Soil displacement in bursting. Fracturing a pipe outward pushes soil against whatever is nearby, which needs thought where a foundation or another utility sits close.
• Specialist dependency. It needs specific equipment and real operator experience, and the failure modes of a badly installed liner are expensive and hard to reverse.

When Digging Is Simply Better

On a short, shallow run across open lawn, open-cut frequently costs less and takes no longer. Trenchless carries mobilisation costs that a small excavator and a day of labour do not, and grass is inexpensive to reinstate. The economics flip in favour of trenchless when there is concrete, mature landscaping or a structure above the pipe — the reasoning is laid out in the cheapest way to replace a sewer line.

Digging also has one advantage nothing else offers: the pipe is visible. The bedding can be corrected, the fall set properly, a cleanout added cheaply while the trench is open, and the finished work inspected directly. On a lateral with multiple problems that is often worth more than keeping the lawn intact. We quote both where both are viable — see sewer line repair — and say plainly which the footage supports.