Sewer scope
Also called: sewer line inspection, sewer camera inspection, drain line scope, lateral inspection
A camera inspection of the main drain line from the house to the street or septic tank, pushed through a cleanout and recorded, to find root intrusion, bellies, offsets, cracks or collapse. $150–$400 as a home-inspection add-on; the line it checks costs $5,000–$25,000 to replace.
The sewer lateral is the one system a standard home inspection can’t see and the one whose failure is among the most expensive in a house. Clay and cast-iron lines from before about 1980 crack, corrode and let roots in; Orangeburg (tar-paper) pipe from the 1940s–70s collapses; even newer PVC can have a belly — a low spot that holds water and waste — from settling. None of it shows until a backup.
A scope takes 30–60 minutes: a self-leveling camera on a push cable goes in through the cleanout and out to the city main or the septic tank, with a locator on the surface marking the depth and position of anything found. The report is video plus notes — the material, the distance to each problem, and a recommendation from cleaning ($200–$500) to spot repair ($1,500–$4,000) to full replacement ($5,000–$25,000, more under a driveway or street).
Order one on any house over about 30 years old, any house with mature trees between it and the street, any history of slow drains or backups, and any house on septic. Inspectors offer it as an add-on at $150–$400, or a plumber does it standalone for $200–$500. A rented camera ($150–$250 a day) can find the obvious — roots, a collapse — but reading a belly or an offset takes experience, and on a purchase the pro’s recording is the document the negotiation runs on.