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  • Plumbing regulations: need to know

    Notifying us of work

    In most cases the installer, owner or occupier must get our consent before work starts on any proposed installation.

    This applies to water system installations or alterations in connection with any of the following:
    • the erection of a building or other structure, not being a pond or a swimming pool
    • the extension or alteration of a water system on any premises other than a house**
    • a material change of use of the premises
    • the construction of a pond or swimming pool over 10,000 litres capacity designed to be replenished automatically with water supplied by us.*

    It also applies to the installation of:
    • a bath having a capacity, as measured to the centre line of the overflow, of more than 230 litres
    • a bidet with an ascending spray or flexible hose**
    • a shower unit of a type specified by the regulator (none specified as yet)*
    • a unit which incorporates reverse osmosis
    • a water treatment unit which produces a waste water discharge or which requires the use of water for regeneration or cleaning
    • a reduced pressure zone (RPZ) valve assembly or other mechanical device for production against a fluid which is in Fluid Category 4 or 5
    • a garden watering system except one designed to be operated by hand
    • any water system laid outside a building either less than 750mm or more than 1,350mm below ground level.

    * see details to be notified below
    ** installation by an approved plumber doesn’t need prior consent but on completion compliance certificate copies must be sent to us and to the person who asked for the work to be done.

    Bathroom bath 300

    Choice of materials and fittings

    Plumbing materials and fittings must meet the standards in the regulations and must:
    • carry an appropriate CE mark in accordance with the EU Council Directive 89/106/EEC

    • conform to an appropriate harmonised standard or European technical approval

    • confirm to an appropriate British Standard or some other European Economic Agreement state specification which provides an equivalent level of protection or performance

    • conform to a specification approved by the regulator.

    Prevention of backflow

    Where water or water-using equipment is used with fluids or materials which could contaminate it, there must be adequate protection to stop the backflow of potentially contaminated water to other parts of the system, especially drinking water. The regulations define fluid risk categories according to the type of contaminants present and specify the type of prevention device which must be fitted to guard against backflow.

    Details to be notified

    For installations connected to our supplies, the following information must be provided on our water supply mains and service application form - see related downloads.

    • The name and address of the person giving notice and, if different, of the person to whom the consent should be sent.
    • A description of the proposed work and any related changes to use of premises.
    • The location of the premises and their use or intended use.
    • A plan of that part of the premises relating to the proposed work and a diagram showing the pipework and fittings to be installed (except for the items marked * above).
    • The plumbing contractor’s name and address if an approved plumber is to do the work.

    Granting consent

    We don’t charge for notifications or for granting consent but work on installations can’t start until consent has been given.

    As the consent letter could contain conditions regarding the plumbing arrangements, it’s important to keep a copy for the installer. Failure to comply with the regulations regarding new installations could mean the water supply is withdrawn. 

    Consent will not be withheld unreasonably and may be granted subject to conditions which must be followed.

    Under the regulations, if consent is not given within 10 working days it is assumed to have been granted. This does not alter the installer, owner or occupier’s obligation to see that the regulations are fully met.

    Enforcing the regulations

    As a water supply company we are responsible for enforcing the regulations and inspect new and existing installations to check they are being met. Our code of practice on enforcement has more information and a copy is available on request. Where breaches are found, they must be remedied as soon as practicable. Where they pose a risk to health, the water supply may be disconnected immediately to protect the health of occupants or others using the same public supply.       

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