Patch lining is the cheapest structural drain repair available and the correct first choice for isolated faults. The packer is towed to the defect on a survey camera, inflated to press the resin sleeve against the pipe wall, and removed once the resin has cured.
The result is a rigid, watertight sleeve bonded to the host pipe. It seals out roots and groundwater and restores structural integrity across the defect without touching the surface above.
Patch lining is not appropriate where the pipe has lost its shape, where there are many defects in one run (full-length lining is more economical), or where the pipe is broken at a junction that needs a specialist junction liner or hat liner.