Drain scaling involves the build-up of hard calcium carbonate deposits, commonly known as limescale, on the internal surfaces of pipework, traps and fittings. The deposits form gradually wherever heated or evaporating water passes through, and over time they reduce effective bore, trap organic residue and increase the risk of blockage. London sits in a recognised hard water area, drawing supply largely from chalk and limestone aquifers, so scaling is particularly common in dishwashers, washing machines, shower wastes and central heating returns. Engineers usually address common causes by descaling traps, jetting affected sections and recommending water softeners or scale inhibitors where appropriate. BS 6700 and Building Regulations Part G cover water supply provisions, and routine cleaning of waste fittings can help slow further scale accumulation.
Drain scaling (limescale build-up)
Hard limescale deposits inside drain pipes, restricting flow in hard water areas.
