What Descaling Does That Snaking and Jetting Cannot
Inside aging cast iron, corrosion forms a hard, layered rust crust called tuberculation that neither a cable nor water pressure fully removes. It grows inward over decades until it narrows the pipe and catches everything that passes. Descaling uses a chain knocker or cutting head to mechanically grind that crust off the wall, restoring the pipe toward the diameter it had when it was installed.
This is a middle path between endless cleanings and full replacement. We camera the line first to confirm the cast iron is sound enough to descale rather than replace, grind the scale back, then jet-flush the loosened material so none of it settles into a low spot to start a new clog. On the right pipe it can add years of service to a line you might otherwise have replaced.
