Plumbing advice

We protect and check the water we provide at every stage, from source to treatment works and then to households and businesses so you can have complete confidence in the quality of the drinking water you receive.


But when the water leaves our pipes and enters private premises, protecting its quality and preventing it being wasted become the responsibility of the owners and occupiers of the premises.

The Water Supply (Water Fittings) Regulations 1999 play an important role in protecting public health, safeguarding water supplies and promoting the efficient use of water within customers’ premises across the UK.

What are the laws around the plumbing in my home?

The Water Supply (Water Fittings) Regulations 1999 set out the installation requirements for plumbing systems. It works the same way as building regulations set out the requirements for buildings.

They set out the legal requirements for the design, installation, operation and maintenance of plumbing systems, water fittings and water-using appliances and supersede the previous Water Supply Byelaws. They have a specific purpose to prevent misuse, waste, undue consumption or erroneous measurement of water and, most importantly, to prevent contamination of drinking water.

Water Regs UK provide national guidance on the regulations for water companies and their customers. Water Companies are responsible for the enforcement of the Regulations within their water supply areas. You can see a copy of our enforcement policy which helps us meet our legal obligations.

Where do they apply?

Since 1 July 1999 in England and Wales, all plumbing systems, water fittings and equipment supplied, or to be supplied, with water from the public water supply come under these regulations. This applies to systems in all types of premises including properties that use a private water supply and have a mains backup provided by water companies. The regulations apply from the point where water enters the property's underground service pipe to the point the water is used.

These regulations do not apply where a property uses a private water supply and doesn't have a supply of water from a water company. However, it is good plumbing practice to follow the requirements of the Regulations.

Who has to comply?

A legal duty is placed on all users, owners or occupiers and anyone who installs plumbing systems or water fittings to ensure they are installed and used in accordance with these regulations. Advanced notice must be given of proposed installations in most cases, so architects, building developers and plumbers have to follow the regulations on behalf of future owners or occupiers.

How do the plumbing laws effect me?

If the plumbing in your home doesn’t comply with the law then you could face a range of plumbing issues from leaking pipes to unpleasant tastes and smells in the water. The Water Regulations are designed to protect public health and keep your water safe. We recommend you follow these three easy steps:

  1. Always use approved fittings and materials in your household plumbing system
  2. Do a simple “plumbing health check to help prevent water quality issues
  3. If you need a plumber, hire one who is WaterSafe approved

More info on how the law affects me

Due to the potential risk posed to public health via backflow, the Government have legislated that plumbing systems must be properly designed, installed, operated, and maintained to meet the requirements of the Regulations.

Home owners and occupiers have a legal duty to comply with the Regulations.

One of the biggest contamination risks to the water supply is from backflow, which can happen when there is a sudden lowering of water pressure in the plumbing system.

This lowering of pressure causes water to flow in the opposite direction and can suck contaminated water, from appliances or industrial processes, back into the drinking water supply.

For example, if someone is using a large amount of water on the ground floor of a building, in some circumstances, water can be sucked back from the upper floors.

Another cause of low pressure can be a burst water main, or the fire brigade drawing off lots of water to fight a fire.  This is a big risk as low-pressure conditions in water mains occur somewhere in the UK about once a minute, 24 hours a day.

Doing some plumbing work in your home?

If you are employing someone to do plumbing work then hiring a WaterSafe approved plumber gives you the peace of mind that your plumbing meets high standards, complies with the law, and protects the quality of your drinking water.

It is also the best way to protect yourself legally. An approved plumber will issue a ‘work completed’ certificate which can provide property owners a legal defence if sub-standard plumbing work is found. The approved plumber would have to pay to correct any sub-standard work.

Further benefits of using an approved contractor?

Approved plumbers are fully qualified to carry out plumbing work in homes and business premises.

They have specific training in Water Fittings Regulations and Byelaws to ensure there should be no risk of poor installation or sub-standard materials that could cause contamination to your drinking water supply.

They will issue a compliance certificate for their work, which provides a defence for property owners who are challenged by a water supplier enforcing the Water Fittings Regulations and Byelaws.

Approved plumbers will be required to put their work right if it does not meet the requirements of the Water Fittings Regulations or Byelaws, enforced by the water supplier.

Should a concern arise, there is an independent complaints procedure in place to resolve any technical disputes about how the work has been carried out.

Approved plumbers are audited to check they are complying with the rules of their Approved Plumber Scheme.

Approved plumbers hold public and employee liability insurance.

Why use approved materials and fittings in plumbing?

Plumbing materials and fittings come into contact with your drinking water supply so they need to be tested, fit for purpose, and safe to use.

Plumbing products and fittings which don’t conform to the water regulations may pose a risk to health, as they can contaminate the drinking water.

Unsuitable products can affect the taste and appearance of drinking water and cause leaks and floods. Households then have to replace faulty products and pay for damage.

If you are doing the plumbing work yourself make sure you know the requirements, not only will the fittings have to be suitable and appropriately installed, in some cases you may also have to notify your local water supplier in advance before carrying out the work.

One of the best ways to ensure you use the correct type of fittings is to use one which is approved. Each component or appliance will have to demonstrate they meet stringent requirements and comply with these regulations and byelaws when correctly installed and used. But you need to be careful, not all fittings are approved for all situations. Some may be limited to specific circumstances. Each component or appliance listed will have advice about any limitations that might apply or installation requirements which need to be considered before using them.

We would suggest you find out whether your internal plumbing conforms to ‘The Water Supply (Water Fittings) Regulations 1999’, which are national requirements for the design, installation and maintenance of plumbing systems, water fittings and water-using appliances.

You can contact one of the following companies to find out whether your water fittings are approved:

Find an approved plumber

We strongly recommend that you use an approved plumber who will be able to ensure that the work complies with the regulations.

WaterSafe is the accreditation scheme for UK plumbers who are approved to work safely with drinking water.

Finding an approved plumber is easy. Just type your postcode into the search bar on the WaterSafe website.

Common plumbing problems

We’ve included a helpful link for some of the most common plumbing problems, including how to detect and fix leaks, causes of noisy pipes, low pressure and controlling water temperature, as well as avoiding dangerous burns and scalding.

Further information and how to contact us?

If you would like to contact Yorkshire Water about Water Regulations inspections, internal water fittings, Water Regulations training, or would just like some guidance on the Water Regulations you can contact the Water Regulations team.

Contact phone number: 01274 804562 (8.30am to 4.30pm Monday to Friday)

Contact email:

Contact address:

Yorkshire Water Services Ltd

Water Quality – Water Regulations

Western Way

Halifax Rd



Water Regs UK are also a great source of information and provide impartial technical support and guidance on the Water Regulations.

Contact Water Regs UK

Where can I find copies of the Regulations and further advice?

The regulations (SI 1999 No. 1148 and No. 1506) and their schedules are available online and can be purchased from HMSO. The text of these documents is included along with detailed water industry guidance and interpretation in the Water Regulations Guide which can be purchased directly from WRAS.

The Water Supply (Water Fittings) Regulations 1999

SI 1999 No1148

SI 1999 No1506 (amendment)

Water Regulations Guide and Water Fittings and Materials Directory

The water regulations guide is the successor to the popular Water Supply Byelaws Guide and includes the full text of the Water Supply (Water Fittings) Regulations and Scottish Water Byelaws, the DETR (DEFRA) guidance clauses and water industry recommendations and interpretations. The guide also includes many clearly illustrated drawings in full colour. The guide is only available as a book.

Yorkshire Water cannot provide a design service for installations but we will try to answer individual queries from customers, designers, builders and installers about the interpretation of the regulations and WRAS can also provide interpretation advice.

Our Water Regulations enforcement policy (PDF)

Advice for customer with rainwater harvesting or greywater reuse systems (PDF)