There are three ways to replace or rehabilitate a residential sewer lateral, and each is genuinely the correct answer in some situations and genuinely wrong in others.
The choice is decided by two facts: what kind of damage the pipe has, and what sits on top of it. Not by which method a contractor owns equipment for.
I’ve watched this decision get made backwards more than once. A few years back, I walked onto a job where a previous crew had already lined a run with a visible dip in it, and nobody had checked whether the pipe still held grade before quoting the liner. The backup was right back within the year, because a liner just takes on the shape of whatever it’s cured inside. In my experience, the contractors worth hiring show up with a camera before they show up with an opinion about which method they’d rather sell you.
| Criteria | Open trench | CIPP lining No-dig | Pipe bursting |
|---|---|---|---|
| Cost per foot | $50–$250 | $80–$250 | $60–$200 |
| Yard & driveway damage | Severe — full excavation | Minimal — 1–2 access pits | Minimal — 2 pits |
| Works on collapsed pipe | Yes | No — needs open path | Usually |
| New pipe lifespan | 50–100 yrs | ~50 yrs | 50–100 yrs |
| Typical time on site | 2–5 days | 1 day | 1–2 days |
| Best for | Shallow lines, full failure, bellies | Cracks & root damage under landscaping | Old clay pipe, same-size swap |
Open trench replacement
What happens: a trench is excavated along the full run, the old pipe is removed, new PVC or HDPE is laid on properly compacted bedding at correct grade, and the trench is backfilled.
Cost: $50–$250 per foot, before restoration.
When it is right
- Collapse. Trenchless methods need a continuous path through the pipe. A collapse has no path.
- A belly. This is the decisive case. Grade can only be corrected by re-bedding the pipe, which means getting underneath it. No liner and no bursting head changes slope. See sewer line belly.
- Under lawn. If the only thing above the pipe is grass, the trenchless premium buys you very little.
- Where the diameter must increase or the alignment must change.
- Shallow lines, where excavation is quick and cheap.
The real cost
The pipe work is rarely what makes an open trench expensive. Restoration is. A driveway is $1,500 to $6,000 to demolish and replace. Mature landscaping cannot meaningfully be replaced at all.
CIPP lining (cured-in-place pipe)
What happens: a resin-saturated felt or fiberglass liner is inverted or pulled into the existing pipe, then cured — with hot water, steam or UV light — into a hard, jointless pipe inside the old one. One or two small access pits, no trench.
Cost: $80–$250 per foot.
When it is right
- Cracks and fractures in pipe that still holds its shape.
- Root intrusion at multiple joints. The liner seals every joint at once, permanently removing the entry points. This is its strongest use case. See tree roots.
- Under driveways, patios, mature trees, additions. Where restoration would exceed the pipe work, lining almost always wins on total cost.
- Corroded cast iron under a slab, where cutting concrete is the dominant expense. See cast iron replacement.
Where it fails
- Collapse — nothing to line against.
- A belly — the liner follows the existing shape, dip included. A lined belly is still a belly.
- Severe offsets — the liner cannot negotiate a step beyond a certain size.
- Badly deformed Orangeburg — usually not a viable host.
Two things to check
A liner reduces the internal diameter slightly. Liner manufacturers typically spec 3 to 6 mm of wall thickness, which is why the effect on a 4-inch lateral in good condition is usually immaterial, and it is often offset by the far smoother surface. On an already-restricted line, ask what the finished bore will be.
Second, lateral connections are covered by the liner and must be reinstated by a robotic cutter afterwards. On a residential lateral there is usually only one. Ask how reinstatement is handled and confirm it is included.
Pipe bursting
What happens: a cone-shaped bursting head is winched through the old pipe, fracturing it outward into the surrounding soil while towing new HDPE in behind it. Two access pits, one at each end.
Cost: $60–$200 per foot.
When it is right
- Old clay pipe — brittle, fractures cleanly, the ideal host material.
- Same-size or upsized replacement — unlike lining, bursting can increase diameter.
- You want new pipe rather than a liner, with the full 50-to-100-year life of HDPE.
- Hardscape above, where a trench would be ruinous.
Where it fails
- Insufficient clearance to other utilities. Bursting displaces soil outward. A gas or water line running close alongside is at real risk, and this is the main reason a contractor will decline the method.
- Non-fracturing pipe. Ductile iron and some steel do not burst cleanly.
- Bellies — the new pipe generally follows the old alignment, sag included.
- Rock or very dense soil — nowhere for the fragments to go.
Choosing, in the right order
Work through this sequence. It is the same order a competent contractor uses. Most professional inspectors grade what the camera finds against the NASSCO PACP (Pipeline Assessment and Certification Program) scale, a 1-to-5 severity rating that gives everyone bidding the job the same reference point for how bad the cracking or root intrusion actually is.
- Is the pipe collapsed? → Open trench. Nothing else is possible.
- Is there a belly? → Open trench for that section. Grade cannot be fixed any other way.
- Is the damage a single isolated defect in sound pipe? → Spot repair, $650–$3,200. Do not buy a full-run solution for a one-point problem.
- Is the pipe intact but cracked or rooted along its length? → Lining or bursting.
- Now look at what is on top. Lawn → open trench is usually cheapest overall. Driveway, patio, mature trees, slab → trenchless usually wins on total cost.
- Is the host pipe clay? → Bursting is well suited. Is it cast iron under a slab? → Lining avoids the concrete.
Trenchless per-foot rates look higher and total project costs frequently come out lower, because the dominant expense in an open trench is putting the surface back. Insist that every quote states, in writing, exactly what restoration is included. A quote reading “backfill only, restoration by others” is not comparable to one that puts your driveway back.
Comparing quotes fairly
Ask every bidder the same seven questions:
- What footage are you replacing or rehabilitating, from where to where?
- What depth are you assuming, and what is the rate if it is deeper?
- What pipe or liner material, and what diameter after installation?
- Are permits included, and who pulls them?
- Exactly what surfaces do you restore, and to what standard?
- What is the warranty — how many years, and does it cover labor?
- What is the named rate for rock, unmarked utilities, dewatering or asbestos-cement pipe?
Give all three the same camera footage and the same locate marks. Otherwise you are comparing assumptions, not prices. Model the expected total with the cost calculator before the quotes arrive.
Frequently asked
Is trenchless always better?
No. Under an open lawn, with a collapsed pipe, or with a belly, open trench is either the only option or the cheaper one. Trenchless earns its premium when restoration would be expensive — which is often, but not always.
How long does a CIPP liner last?
Around fifty years is the standard design assumption, with the material standard being ASTM F1216. Installation quality is what actually determines it: resin ratio, cure temperature and time. Ask what the warranty covers and for how long.
Can trenchless be done in winter?
Bursting and open trench become harder and more expensive in frozen ground. CIPP is comparatively insensitive since most of the work happens inside the pipe, though resin cure times change with temperature and a competent installer accounts for that.
Does the liner reduce flow?
Slightly reduced diameter, considerably smoother wall. On a residential lateral in reasonable condition the net effect on capacity is negligible and sometimes positive. On an already-restricted line, ask for the finished internal diameter.
Which method has the best warranty?
Warranty length varies far more by contractor than by method — anything from one year to fifty. What matters is what the warranty actually covers: materials only, or materials and labor, and whether it survives a change of ownership. Get it in writing before signing.
Pricing surveyed August 2026. See the Methodology.
