Sewer inspection terminology

Cast iron was the dominant residential lateral material from the early 1900s through the 1970s. It's heavy, dimensionally stable, and tolerates high water temperatures — but corrodes from the inside out, eventually losing wall thickness and forming rust scale that catches grease and toilet paper. Most residential cast iron you'll inspect today is at or past its 50-75 year design life.

• ·Typical lifespan: 50-75 years
• ·Failure modes: pitting, scale build-up, channeling along bottom
• ·Replacement: usually with PVC or HDPE
• ·Identification: dark grey/black, sometimes with red rust scale

Vitrified clay was the standard outside-the-building lateral material from roughly 1900 to the early 1980s. Fired clay is essentially impervious to chemical corrosion and lasts indefinitely IF undisturbed — but it's brittle, joins are mortared (offering an easy root entry path), and earth movement cracks it. The classic 'roots in the line' homeowner call is almost always vitrified clay.

• ·Typical lifespan: indefinite if undisturbed
• ·Failure modes: root intrusion at joints, cracking from earth movement
• ·Joint sealant: originally mortar, later bituminous compound
• ·Identification: orange/brown/tan exterior, smooth glazed interior

PVC (polyvinyl chloride) became the dominant residential lateral material starting in the 1970s. It's lightweight, easy to join with primer+cement, and immune to most chemical corrosion. Failure modes are mechanical — crushing under load, joint pull-out from earth settlement, or solvent-weld failure on a bad install. Most modern repairs and replacements use Schedule 40 PVC.

• ·Typical lifespan: 50-100 years
• ·Failure modes: crushing, joint separation, brittleness in cold
• ·Common spec: ASTM D3034 SDR-35 or Schedule 40
• ·Identification: smooth white interior, slip-fit gasket or solvent joints

Orangeburg pipe — bituminous-impregnated wood fiber — was widely installed from the 1940s through the early 1970s as a cheaper substitute for cast iron. It famously deforms under load: the cross-section goes from round to oval and eventually collapses. If you scope a 1950s-era house and see what looks like a slightly egg-shaped pipe, it's almost certainly Orangeburg and almost certainly at end-of-life. Replacement is the only durable repair.

• ·Typical lifespan: 30-50 years (most are now failing)
• ·Failure modes: deformation, delamination, total collapse
• ·Class action: yes, in some states — check local statutes
• ·Identification: dark interior, oval cross-section, layered wall

ABS (acrylonitrile butadiene styrene) was used heavily for residential DWV (drain-waste-vent) inside the building footprint, particularly on West Coast new construction from the 1970s through the 1990s. Newer ABS is fine; some early ABS runs developed brittleness and longitudinal cracking. Joints are solvent-cemented like PVC. Most under-slab failures we see are in pre-1990 installations.

• ·Typical lifespan: 50+ years (some early runs failing early)
• ·Joints: solvent-cement (black ABS-specific glue)
• ·Common spec: ASTM D2661 or D2680
• ·Identification: black with smooth interior

HDPE (high-density polyethylene) is the workhorse of modern trenchless replacement. It comes in long fused sections (no joints between fusion welds) so root intrusion is essentially eliminated. Pipe-bursting installs pull HDPE through the old failing line, expanding the bore as it goes. Expected service life is 100+ years.

• ·Typical lifespan: 100+ years
• ·Joints: heat-fused (no glue or gaskets)
• ·Install method: trenchless pipe-bursting or open trench
• ·Identification: smooth dark interior, no visible joints

CIPP (cured-in-place pipe) is the dominant trenchless rehabilitation method. A resin-saturated felt or fiberglass sock is inverted into the existing pipe and cured with heat, steam, or UV light — creating a structural liner with a smooth interior. The liner is typically rated for 50+ years and eliminates root intrusion at joints (the joints are now sealed under the liner). Identified on camera as a uniform light-colored smooth wall with no visible joints.

• ·Typical lifespan: 50+ years
• ·Install: no excavation, single access pit
• ·Visual: smooth, uniform color, no joints visible
• ·Common materials: felt+epoxy, fiberglass+UV resin

Concrete pipe is more common in larger-diameter laterals (8"+) and municipal mains than in 4" residential service. Reinforced concrete pipe (RCP) carries a rebar cage. Concrete's principal failure mode in sewers is sulfide corrosion of the crown (top half) from hydrogen sulfide gas produced by anaerobic bacteria. Identified by a rough grey/tan interior, often with visible aggregate.

• ·Typical lifespan: 50-100 years
• ·Failure modes: H2S crown corrosion, joint deterioration
• ·Common in: large-diameter laterals, municipal mains
• ·Identification: rough grey/tan interior with aggregate

A CCTV inspection where a self-leveling camera is pushed through the lateral on a flexible rod, recording video of the pipe interior from the cleanout to the city main. Standard length for residential is 50-100 feet. Used pre-purchase, pre-repair, and as the routine diagnostic for chronic backups.

The pipe running from a single home to the municipal sewer main in the street. Typically 4 inches (sometimes 6) in diameter and 50-150 feet long depending on lot depth. Property owners are responsible for the lateral up to the main connection (and sometimes the connection itself, depending on jurisdiction).

The standard inspection-coding system developed by NASSCO (National Association of Sewer Service Companies). Every observation in a PACP-coded report uses standardized codes (RFC, CC, F, etc.) with severity grades 1-5. Most municipal acceptance standards and many insurance claim processes require PACP-certified inspectors.

An access point in the lateral with a removable cap, typically at the foundation wall or in the yard. The cleanout is where the inspection camera enters and where rodding/jetting equipment is fed.

Pipe repair or replacement that doesn't require digging a continuous trench. Includes CIPP lining (cured-in-place pipe), pipe bursting (HDPE pulled through the old line), and point repair (localized liner at a single defect). Generally more expensive per foot than open-trench but avoids landscape destruction.

A sagging section of pipe where the slope reverses, creating a pool of standing water. Bellies catch debris and grease, requiring more frequent cleaning. Caused by soil settlement under the pipe or improper original install grade.

High-pressure water cleaning using a flexible hose with a forward/reverse nozzle. Cuts roots and emulsifies grease much more effectively than mechanical rodding. Often the recommended cleaning before a CIPP lining install.