Inversion lining is an alternative CIPP installation technique where the resin-saturated liner is turned inside-out as it is pushed or pulled into the host pipe using water pressure or air pressure, rather than being pulled in on a mandrel. As it inverts, the resin-coated face is pressed against the pipe wall under the installation pressure, ensuring consistent contact along the full run before curing begins.

Inversion is particularly well-suited to pipes with significant bends, changes in direction, or access conditions where a pulled liner installation would be difficult to manage. The cured liner delivers identical structural and hydraulic performance to standard CIPP installation — a jointless, root-resistant, corrosion-proof pipe within a pipe — with design life exceeding 50 years.