Skip to content
Old House Sewer LinesSewer lines and drains in older Westchester homes
Topics

When a sewer line can't be lined

Updated October 30, 2026 · 2-minute read · Old House Sewer Lines

Trenchless sewer repair by lining will not work when the old pipe is collapsed, back-pitched or too fragile to clean. The City of Fairfax, Virginia states the reason plainly in its lateral program: whatever shape the old pipe has, the cured liner inherits, so a host in any of those three conditions is disqualified (City of Fairfax, archived).

Fairfax adds two rules that apply anywhere. Lining does not correct structural defects, which must be repaired first, and a CCTV recording of the line decides whether it qualifies.

The three disqualifiers

Collapsed pipe. A liner needs an open path to travel through and a wall to cure against. Where a section has caved in, there is nothing to line. Roots are a common cause: a Traverse City, Michigan sewer FAQ says root growth in a crack or joint can break the pipe "and may result in total collapse" (Traverse City).

Back-pitched pipe. If part of the lateral runs uphill or sags into a belly, waste settles there. A liner follows the same profile, so the low spot survives the repair. Section 704.1 of the state plumbing code calls for uniform alignment and uniform slope, and its table sets the least allowable fall for typical house-sewer sizes (PCNYS chapter 7). Only excavation resets the grade. Sewer line slope and depth covers the code numbers.

Fragile pipe. Fairfax singles out Orangeburg, the tar-and-paper fiber pipe, saying the hydro-jetting used to clean a line before lining may damage it and make it ineligible. The City of Tempe, Arizona describes the same material flattening out of round as it deteriorates (City of Tempe, archived). Tempe's dates are for Arizona; when Orangeburg was used in Westchester was not confirmed. See Orangeburg pipe.

What the video has to show

Eligibility rests on the camera, and the camera has limits. NASSCO's CCTV specification names, as an unforeseen hazard, a hole that sits beneath the waterline in the pipe where the lens cannot see it, and calls for flow to be controlled so the whole circumference shows (NASSCO). Ask whether the recording covers the entire lateral, from the house to the main, with the water held back. What a sewer camera cannot show has more.

What is left when lining is out

Open-trench replacement remains, in EPA's 2004 words, the most widely used and proven fix for a failing lateral (EPA Appendix L). A mixed approach is also possible: excavate the collapsed or sagging stretch, then line sound pipe on either side, following Fairfax's rule that structural defects come first. EPA describes pipe bursting as fracturing the old pipe into the soil while pulling in new pipe of the same or larger size; the state code limits it on house sewers to 6 inches and smaller. Spot repair versus full replacement and the repair topic page compare the options.

Lining, bursting and excavation are licensed contractor work with permits. In Westchester, ask the city or village building department which permits apply, since this site could not confirm them town by town.

Key facts

  • Fairfax, Virginia bars lining where the host pipe has collapsed, slopes backward or is too brittle (Fairfax).
  • Lining does not correct structural defects; they are repaired first, and the CCTV recording decides eligibility.
  • Fairfax warns that pre-lining jet cleaning can wreck brittle Orangeburg fiber pipe.
  • The state code's minimum grade for 3-inch through 6-inch drainage lines is one-eighth inch of drop per foot (Table 704.1) (ICC).
  • Defects submerged below the flow can escape the camera, per NASSCO's CCTV guideline (NASSCO).

Sources