BS 6700 (water supply systems)

BS 6700 was a long-standing British Standard giving design and installation guidance for cold and hot water services in buildings. While now formally withdrawn and superseded by BS EN 806 and related standards, BS 6700 is still regularly referenced in older specifications and historic project documentation across UK plumbing, including London commercial fit-outs. Practical implications for homeowners and contractors include recognising that designs originally compliant with BS 6700 are not automatically non-compliant under the current European standards, but new work should be specified to BS EN 806 and the Water Supply (Water Fittings) Regulations 1999. The standard covered cold water storage, hot water generation, pipework sizing and corrosion prevention. The formal current references are BS EN 806 parts 1 to 5 covering specifications, design, installation, commissioning and operation of water supply systems.