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This Code of Practice, S.R. 50-3, sets out the requirements for the design, installation and commissioning of domestic cold-water and domestic hot-water supply systems in domestic dwellings.

This Code of Practice is complementary to the I.S EN 806 series of European Standards which have been adopted as Irish Standards:

This Code of Practice supports the Building Regulations Technical Guidance Document G – Hygiene.

The main objectives of this Code of Practice are to ensure that:

— deterioration in water quality within the water supply system is avoided;

— the required flow of water and pressure is available at the draw-off points and at the connection points of water using appliances;

— the potable water meets the standards for the physical, chemical and microbiological quality at the draw-off points;

— all parts of the water supply system do not cause danger to health and do not damage property within calculated lifetimes;

— the maintenance of the water supply system meets the functional requirements at all times during its lifetime;

— sound levels are kept to a practicable minimum; and

— contamination of the public water supply, undue water consumption leakage and misuse is avoided.



This Code of Practice specifies the requirements for and gives recommendations on the design, installation, alteration, testing, maintenance and operation of potable water supply systems within dwellings and for pipework outside of dwellings but within the curtilages.

It covers the system of pipes, fittings and connected appliances installed for supplying potable water, cold water and hot water in a dwelling.

Where there is a private potable water supply within the property boundary, the scope of this document also covers the pipe system from the point of entry from that private water supply.

The sphere of application ends at the downstream end of the potable water supply system at the draw off and connection points.

The piping of the waste water drainage system within the dwelling is not within the scope of this document. Greywater recovery systems are included in the scope of this Code of Practice.

The heating system to provide heat to domestic hot water is not within the scope of this document. Water based heating systems are covered by S.R. 50-1 and solar thermal heating is covered by S.R. 50-2.

Have your say at:

Public enquiry closes: 18-09-2019

Readers are warned that this draft is subject to ongoing development and change. Any comments or proposed changes submitted will be considered by the relevant technical panel.