IRRIGATION WINTERISATION GUIDE FOR SOUTH LONDON GARDENS

When water freezes, it expands by about 9 per cent, creating destructive internal pressure in a closed irrigation system. In South London’s variable winter climate, unprotected solenoid valves, backflow preventers and lateral pipework are at serious risk of catastrophic failure. This guide explains how to decommission your system correctly so manifolds, valves and controllers survive the freeze–thaw cycle and are ready to restart in spring.