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Cold water supply

The water company will provide from their mains tapping plug cock a communication pipe to a stop valve and protection chamber just outside the boundary; this is a chargeable item to the building owner. The goose neck bend is included to relieve any stress likely to be exerted on the mains connection.
A service pipe is taken from this stop valve to an internal stop valve, preferably located just above floor level on an internal wall or at least 600 mm from an external wall. The stop valve should have a drain off valve incorporated in it, or just above it, so that the service pipe or rising main can be drained.
Care must be taken when laying a service pipe that it is not placed in a position where it can be adversely affected by frost, heavy traffic or building loads. A minimum depth of 750 mm is generally recommended for supplies to domestic properties; where the pipe passes under a buildĀ¬ing it should be housed in a protective duct or pipe suitably insulated within 750 mm of the floor level .
Suitable materials for service pipes are copper, PVC, polythene, lead and galvanised steel. Copper service pipes can be laid on and covered by a layer of sand to prevent direct contact with the earth or alternatively wrapped with a suitable proprietary insulating material. Plastic coated copper pipes are also available for underground pipework. Steel pipes should have a similar protection but plastic pipes are resistant to both frost and corrosion.