Regulations

The Water Supply (Water Fittings) Regulations 1999 protect public health by setting out requirements for plumbing systems, safeguarding our drinking water.

They prevent water contamination, misuse, waste and excessive consumption and safeguard against wrong usage readings.

The Water Regs UK provides regulatory guidance for water companies and their customers across the UK, and we’re responsible for enforcing them across our region.

Water Supply (Water Fittings) Regulations 1999

Where do they apply?

To all properties - businesses and homes - with a private water supply and a mains backup (provided by a water company). They cover all plumbing systems, water fittings and equipment (in place or to be delivered) using the public water supply, beginning from the point where water enters the underground service pipe to where it’s used.

They do not apply if you have a private water supply not provided by a water company*. It is, however, good plumbing practice to follow the Regulations’ requirements.

*Under Private Water Supply Regulation 8 where a supply is redistributed by a customer to another party the fittings Regulations would apply.

Who has to comply?

Users, owners, occupiers, architects, building developers or anyone installing plumbing systems or water fittings. In most cases, you must notify us of any proposed installations. You can do this here:

If your plumbing system or water fitting was installed before the Regulations came into force, it’s likely it complies with the Water Supply Byelaws. It would only fail if it’s impacting water quality.

What are approved plumbers?

Plumbers who are trained to work safely with drinking water and so meet the regulatory requirements. They issue certificates confirming their installation or maintenance work complies with the Regulations. If any Regulation breaches are then found in their certified work, the legal responsibility falls upon them and not the owner or occupier.

The UK body WaterSafe aims to raise plumbing standards by listing qualified plumbing and heating professionals in your area. Find one here.

How do I comply with the Regulations?

If you’re carrying out any plumbing work, we strongly recommend you find out more about the Regulations or employ a suitably-qualified plumber. This protects your water quality and could prevent costly alterations if we carry out an inspection.

If you’re having work carried out on your behalf, ensure the person or company you employ is aware of and meets the Regulations’ requirements. Find approved plumbing businesses here.

How are the regulations enforced?

The Government requires water suppliers to enforce the regulations within their area of supply and as a result, we inspect new and existing installations. If:

Regulation breaches are found, we'll ask for them to be remedied as soon as is practicable
The breaches pose a risk to health, we may disconnect the premises’ water supply, protecting the health of the occupants or others using the same supply. It is a criminal offence to breach the Regulations and offenders may face prosecution.
Find out more about our enforcement policy here.

Where can I find the Regulations and further advice?

You can find the Regulations and further advice here.

Plumbing fittings

It’s not illegal to sell unsuitable fittings and appliances, but it is illegal to install one, so check suitability before you buy. The Water Regs UK can tell you what’s been tested and complies with the Regulations.

Water Supply (Water Fittings) Regulations 1999 document

Water Supply (Water Fittings) (Amendment) Regulations 1999 document

Government's Guidance to the Water Fittings Regulations

Regulatory changes

Double check valves (DCVs) on household appliances

In April 2017, the Water Regs UK changed the installation requirements of the Water Supply (Water Fittings) Regulations 1999. At the point where an appliance, such as a dishwasher or washing machine, is connected to the water supply, it will need an additional DCV installed. The revised wording’s below:

IRN 160
“A compliant double check valve or some other no less effective device providing backflow prevention protection to at least fluid category three shall be fitted at the point of connection(s) between the water supply and the fitting or appliance. Where the double check valve is for use with products that incorporate water injected with CO2 gas all metal parts in contact with the water passing through it must be constructed from chrome nickel stainless steel.”

IRN 360
“Domestic unvented primary circuits may be filled or replenished by means of a temporary connection between the primary circuit and the supply pipe. An ‘Approved’ double check valve shall be installed at the point of connection to the supply pipe. A permanent connection between the primary circuit and the supply pipe may be made via a CA backflow prevention device or some other no less effective backflow prevention device.”

Historically, it was assumed all domestic appliances were fitted with DCVs so internal inspections would have passed. Our Customer Services Representatives will now fail all domestic internal inspections if appliances do not have the fitting.

Our Guide ‘Water Regulations for Domestic Properties’ should be able to answer any questions you have on this.

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