Methodology
Every figure the tools use, imported directly from the same code they run. If you disagree with an assumption, you can see exactly which number to change.
Pipe work, per foot
Installed cost per linear foot before restoration, from HomeAdvisor and NuFlow cost data (2025–26).
| Method | Per foot |
|---|---|
| Dig and replace (open trench) | $100 – $250 |
| Pipe bursting | $80 – $220 |
| Pipe lining (CIPP) | $90 – $250 |
| Spot repair (one section) | $1,000 – $4,000 per section, regardless of line length |
| Open trench under a slab | plus $300 – $350 per foot |
Depth and regional factors
Depth multiplies open-trench and spot-repair pipe work fully, pipe bursting by half as much (pits are deeper but the pipe isn’t trenched), and lining not at all. Regional labour multiplies pipe work, restoration, the cleanout and the street section; permit and camera fees are not scaled.
| Depth | Factor |
|---|---|
| Shallow — under 4 ft | × 0.85 |
| Typical — 4 to 8 ft | × 1 |
| Deep — over 8 ft | × 1.35 |
| Region | Factor |
|---|---|
| Lower-cost area | × 0.85 |
| Average | × 1 |
| High-cost metro | × 1.3 |
Restoration, by method and surface
An open trench restores the whole run, bursting restores two pits, a spot repair one pit, and lining usually nothing. Driveway replacement ranges draw on NuFlow’s $1,000–$5,000+ figure.
| Method | Lawn | Landscaping, trees or a fence | Driveway, patio or sidewalk | Under the house slab |
|---|---|---|---|---|
| Dig and replace (open trench) | $300 – $1,200 | $1,500 – $4,000 | $2,000 – $6,000 | $1,500 – $4,000 |
| Pipe bursting | $200 – $600 | $500 – $1,500 | $800 – $2,500 | $2,000 – $6,000 |
| Pipe lining (CIPP) | $0 – $300 | $0 – $300 | $0 – $500 | $0 – $500 |
| Spot repair (one section) | $150 – $500 | $400 – $1,200 | $700 – $2,000 | $1,000 – $3,000 |
Fixed items
| Item | Range | Source |
|---|---|---|
| Permit and inspection | $100 – $500 | HomeAdvisor lists about $200; municipal fees vary |
| Camera inspection | $150 – $500 | HomeAdvisor $100–$500 |
| New outdoor cleanout | $650 – $2,000 | Angi, one-way cleanout $650–$2,000 |
| Street or right-of-way section | $3,000 – $15,000 | Widest range in the model; city standards vary and some cities pay for it |
All lines are rounded to the nearest $50. Emergency and after-hours pricing — commonly 25–100% more — is not included.
How the quote check works
A quote more than 25% below the bottom of the range, or more than 30% above the top, is flagged as well outside it; anything beyond the range by less is flagged as slightly outside. Scope flags don’t depend on price at all — they compare the method quoted with the defect reported: lining for a belly or through a collapse, lining or a spot repair on Orangeburg, bursting under a slab, open trenching under concrete, and any large job quoted without camera footage.
How the clog-or-broken checker scores causes
Each cause carries a weight from 1 to 5 for each symptom it explains. A cause’s score is the sum of its weights for the symptoms selected, divided by five times the number selected, so a cause that strongly explains everything ticked scores close to 100%. The weights are set so that cheap, local causes outrank a broken line unless there is outdoor evidence.
| Cause | Symptoms it explains (weight) |
|---|---|
| A clog in one fixture's drain | Only one drain is slow or blocked (5); Smell in one room only (1); Toilet or drains gurgle (1) |
| A dry trap, failed wax ring or blocked vent | Smell in one room only (5); Sewage smell through the house (3); Toilet or drains gurgle (2) |
| A clog in the main sewer line | Several drains are slow at the same time (5); Backs up when the washer drains or a toilet flushes (5); Water comes up at the lowest drain (4); Toilet or drains gurgle (3); Sewage smell through the house (2) |
| Tree roots growing into the line | Roots came out on the snake (5); The clog keeps coming back (5); Several drains are slow at the same time (2); A strip of greener, faster-growing grass (2); Water comes up at the lowest drain (1) |
| A belly (sag) in the line | The clog keeps coming back (4); Several drains are slow at the same time (2); Water comes up at the lowest drain (1); Backs up when the washer drains or a toilet flushes (1) |
| A broken or collapsed section | Soggy patch, sinkhole or sewage smell in the yard (5); Rats, roaches or flies coming from drains (4); A strip of greener, faster-growing grass (3); The clog keeps coming back (2); Sewage smell through the house (1); Several drains are slow at the same time (1); Water comes up at the lowest drain (1) |
| Cracks letting groundwater into the line | It only happens during or after heavy rain (3); Soggy patch, sinkhole or sewage smell in the yard (1); The clog keeps coming back (1); Water comes up at the lowest drain (1) |
| A blockage or overload in the public sewer | Neighbors have the same problem right now (5); It only happens during or after heavy rain (4); Water comes up at the lowest drain (3); Several drains are slow at the same time (1) |
How the protection plan calculator works
Annual cost is the monthly fee times twelve. The plan pays the lower of the repair cost and its cap, less any deductible. The break-even interval is what the plan pays divided by the annual cost — how often a covered repair would need to happen for fees and payouts to match. The calculator doesn’t estimate a failure probability, because no public data supports one for an individual lateral.
- Default plan: $8.99 a month with a $10,000 cap — within the $4.99–$11.99 range published for Service Line Warranties of America plans.
- Service line add-on comparison: $20–$50 a year, a $10,000 limit and a $500 deductible (NerdWallet), evaluated at the middle of the price range.
| Material | Service life used for context | Basis |
|---|---|---|
| PVC or ABS plastic | 50–100 years | Joints are glued or gasketed and roots rarely get in. Failures are usually installation faults — poor bedding causing a belly. |
| Cast iron | 50–100 years | Corrodes from both sides. The bottom wears into a channel first; corrosive or salty soil can cut life to 25 years. |
| Clay (vitrified clay) | 50–100 years | The fired clay lasts; the joints every two to three feet do not. Root intrusion at joints is the usual failure. |
| Orangeburg (fiber pipe) | 30–50 years | Wood-pulp fibre and tar that softens and ovalises under soil load. Known to fail in as little as 10 years. |
| I don't know | 30–100 years | A camera inspection identifies the material in minutes, and it is the single biggest factor in the answer. |
Principal sources
- HomeAdvisor — sewer main repair cost data, per-foot costs by method, restoration and permit figures.
- NuFlow — residential sewer repair cost estimates, trenchless versus excavation comparison, lining versus bursting.
- Angi — sewer cleanout installation cost.
- NerdWallet — service line coverage cost, limits and deductibles.
- Agency for Toxic Substances and Disease Registry — hydrogen sulfide ToxFAQs and medical management guidelines.
- Wikipedia, the City of Ann Arbor and Nordic Home Inspection — Orangeburg pipe composition, eras and lifespan.
- ConsumerNotice.org and plumbing contractor guidance — cast iron lifespan and failure modes.
- Los Angeles County Public Works, NYC DEP, the City of St. Louis and EBMUD — sewer lateral responsibility and programmes.