Compliant Water Fittings

If a premises has any form of mains water supply, then the water fittings regulations in England, Wales and Northern Ireland, byelaws in Scotland, apply.

These legal requirements play an important role in protecting public health and safeguarding water supplies. Their purpose includes preventing the contamination and waste of water supplied by a water undertaker once it has entered a customer’s plumbing system.

Regulation/byelaw 4 sets specific requirements for water fittings, these include being:

of an appropriate quality and standard
suitable for the circumstances in which they will be used
compliant with any applicable requirements set out in schedule 2
installed in a workmanlike manner.

Please note where they apply other requirements and items of legislation must also be complied with.

Related FAQs

What is meant by an appropriate quality and standard?

<h1 id="what-is-a-water-fitting-of">What is a water fitting of an appropriate quality and standard?</h1><hr><figure class="img-responsive" style="float: right; margin-left: 20px; margin-right: 0px; width: 288px; min-width: auto; min-height: auto;"><img src="/images/topics/faqs/coverb-reg_4_1_a__compliance_guidance_april_2021_v1.1.png" class="img-responsive" style="width: 100%"></figure><p class="p1">To help prevent contamination and waste of mains water supplies the water fittings regulations in <a href="https://www.legislation.gov.uk/uksi/1999/1148/contents">England, Wales</a> and <a href="https://www.legislation.gov.uk/nisr/2009/255/contents/made">Northern Ireland</a>, <a href="https://www.scottishwater.co.uk/Help-and-Resources/Document-Hub/Business-and-Developers/Byelaws-and-Trade-Effluent">byelaws in Scotland</a>  include specific requirements for water fittings. These include the legal requirement to be of an appropriate quality and standard for installation [regulation 4 (1)(a) & 4(2)].</p><p class="p3">This regulation requires water fittings, and water using appliances, to either:</p><ul><li><p>Conform to an appropriate British Standard (or some other national specification which provides an equivalent level of protection and performance)</p></li></ul><p>Or</p><ul><li><p>Conform to a specification approved by the regulators</p></li></ul><p class="p1">If the water conveyed by these fittings needs to be wholesome – drinking water standard - any non-metallic materials or components within the fitting or appliance which comes into contact with water must also conform to the current version of <a href="https://knowledge.bsigroup.com/products/suitability-of-non-metallic-materials-and-products-for-use-in-contact-with-water-intended-for-human-consumption-with-regard-to-their-effect-on-the-quality-of-the-water-specification/standard">BS 6920</a> (or an equivalent).</p><p>Any questions please contact the local water undertaker for advice.</p><p><br></p><h1 id="topics">FAQs</h1><p><br></p>

What is meant by evidence of regulation 4(1)(a) compliance?

<h1 id="what-is-meant-by-evidence-of">What is meant by evidence of regulation 4(1)(a) compliance?</h1><hr><h4 class="p1" id="what-is-meant-by-evidence-of"> </h4><figure class="img-responsive" style="float: right; margin-left: 15px; margin-right: 10px; width: 212px; min-width: auto; min-height: auto;"><img src="/images/topics/faqs/coverb-reg_4_1_a__compliance_guidance_april_2021_v1.1.png" class="img-responsive" style="width: 100%"></figure><p class="p1">This is evidence to show a water fitting is of an appropriate quality and standard for installation. </p><p class="p1">Water undertakers will consider evidence of compliance provided on a case and site specific basis. </p><p class="p1">Whilst this evidence must satisfy another regulation [4(2)], water undertakers have no preference for, or require it to be in a specific form. Typically, they will consider declarations of performance issued against designated standards, product certification and test reports.  </p><p class="p1"><strong>Please note: </strong></p><ol><li><p>Because a water fitting must comply with all parts of the regulations being of an appropriate quality and standard does not, of itself, guarantee compliance with the regulations. </p></li><li><p>The latest available edition or version of guidance or specifications should always be used. </p></li><li><p>In respect of equivalence water undertaker retain absolute discretion in assessing whether a national specification provides an equivalent level of protection and performance to that specified in an appropriate British Standard. For information regarding the equivalence of a performance specification please contact your water undertaker.<br></p></li></ol><p class="p5">For further information please refer to <a href="/downloads/publications/booklets/reg_4__1__a__compliance_guidance_april_2025_v2.0.pdf">Regulation 4(1)(a) compliance guidance</a> and <a href="/downloads/publications/booklets/regulation_4_1__a__guidance_bs_6920_compliance_overview_april_2025_v2.0.pdf">BS 6920 Compliance Overview.</a></p><p class="p1">Any questions please contact the local water undertaker for advice.</p><p><br></p><h1 id="topics">FAQs</h1><p><br></p>

Is conformity with BS EN 61770 acceptable evidence of compliance for whitegoods ?

<h1 id="is-conformity-with-bs-en-61770">Is conformity with BS EN 61770 acceptable evidence of compliance for whitegoods ?</h1><p><br></p><hr><p>Some but not all appliances incorporate backflow protection which satisfies UK requirements, conformity with BS EN 61770 does not. If the backflow protection built in is not adequate the appliance must be supplied via an independent appropriate form of backflow protection.</p><p>Please refer to the <a href="https://www.waterregsuk.co.uk/information/publications/information-leaflets/">'Whitegoods' information leaflet</a> for further information.</p><p> </p><p> </p><p> </p><h1 id="topics">FAQs</h1><p><br></p>

How will I know if a water fitting is suitable for installation?

<h1 id="how-will-i-know-if-a">How will I know if a water fitting is suitable for installation?</h1><hr><h4 id="how-will-i-know-if-a"></h4><p>Establishing whether a water fitting is suitable for installation is dependent upon a number of factors including but not limited to:</p><ul><li><p>Water fittings must be of an appropriate quality and standard</p></li></ul><ul><li><p>System design, things considered include but are not limited to compatibility:</p><ul><li><p>with other water fittings within a plumbing system (e.g the potential for galvanic action)</p></li><li><p>system operational parameters (e.g. the maximum* and minimum pressure, temperature and flow the systems will be operating at)</p></li></ul></li></ul><ul><li><p>Location specific factors, things considered include but are not limited to:</p><ul><li><p>the environment (e.g. ground or airborne contamination, the risk of frost damage, corrosion or dezincification)</p></li><li><p>product installation requirements and/or constraints (e.g. installed where light is excluded or only above ground)</p></li><li><p>installation backflow risks (e.g. the need for backflow protection to be installed)</p></li></ul></li></ul><ul><li><p>Requirements of schedule 2 as applicable.</p></li></ul><p>If the proposed plumbing work is notifiable, the suitability of water fittings will be assessed as part of the notification process. </p><p>If the installation is not notifiable there remains a legal obligation for the installer and premises owner or occupier to ensure the plumbing work is fully compliant with the water fittings regulations in <a href="https://www.legislation.gov.uk/uksi/1999/1148/contents">England, Wales</a> and <a href="https://www.legislation.gov.uk/nisr/2009/255/contents/made">Northern Ireland</a>, <a href="https://www.scottishwater.co.uk/Help-and-Resources/Document-Hub/Business-and-Developers/Byelaws-and-Trade-Effluent">byelaws in Scotland</a>. Therefore, if in doubt, contact the local <a href="https://www.waterregsuk.co.uk/contacts/water-company-contacts/">water undertaker</a> for advice.</p><p> </p><p>*Please note all water fittings must be capable of withstanding an internal water pressure of not less than 1½ times the maximum pressure it will be subject to in operation.</p><p> </p><p> </p><h1 id="topics">FAQs</h1><p><br></p>

When does schedule 2 paragraph 2 not apply?

<h1 id="when-does-schedule-2-paragraph-2">When does schedule 2 paragraph 2 not apply?</h1><hr><h4 id="when-does-schedule-2-paragraph-2"></h4><p>Providing appropriate and adequate backflow protection against the highest level of risk downstream is installed, an installation not used to supply water for drinking, bathing, food preparation or cooking purposes is exempt from complying with schedule 2 paragraph 2(1). <br></p><p>Please note the backflow protection required needs to be assessed by the local water undertaker and other requirements of the water fittings regulations/byelaws continue to apply.</p><p> </p><p> </p><h1 id="topics">FAQs</h1><p><br></p>

What should be considered when designing a plumbing system?

<h1 id="what-should-be-considered-when-designing">What should be considered when designing a plumbing system?</h1><hr><p>When designing a compliant plumbing system a number of factors need to be considered, including but not limited to:</p><ul><li><p>Avoiding the risk of contamination or damage resulting from the environment in which the system is to be installed or due to the design itself.</p></li><li><p>The required and attainable supply pressure and other operational parameters</p></li><li><p>User expectations and whether these are achievable</p></li><li><p>Suitability of water fittings for use</p></li><li><p>Providing appropriate, adequate backflow protection.</p></li><li><p>Water efficiency</p></li><li><p>Limiting waste.</p></li></ul><p>Useful sources of information include <a href="https://knowledge.bsigroup.com/products/specifications-for-installations-inside-buildings-conveying-water-for-human-consumption-general/standard">BS EN 806 </a>and <a href="https://knowledge.bsigroup.com/products/guide-to-the-design-installation-testing-and-maintenance-of-services-supplying-water-for-domestic-use-within-buildings-and-their-curtilages-complementary-guidance-to-bs-en-807/tracked-changes">BS 8558</a></p><p> </p><p> </p><h1 id="topics">FAQs</h1><p><br></p>

What should be considered when selecting and installing pipework

<h1 id="what-should-be-considered-when-selecting">What should be considered when selecting and installing pipework</h1><hr><h4 id="what-should-be-considered-when-selecting"></h4><p>To help prevent waste and contamination all pipe and fittings systems must be of an appropriate quality and standard and suitable for the circumstances in which they will be used.</p><p>Before installing a pipe and fittings system key considerations will include but are not limited to:</p><ul><li><p>The compatibility of the pipe and fittings. For example, to ensure connections are watertight and configured to prevent galvanic action.</p></li><li><p>Whether the pipework is to be installed above or below ground</p></li><li><p>Where the pipework is to be installed. For example, in contaminated ground, in a duct and potentially exposed to construction materials and/or water vapour, somewhere exposed to sunlight or sources of heat.</p></li><li><p>What water temperatures and pressures the pipework will be exposed to. For example, hot or cold water only, heating systems, maximum operating pressure and thermal shock.</p></li><li><p>In the case of metallic water fittings, the possibility of corrosion due to galvanic action and dezincification.</p></li></ul><p>Useful sources of information include <a href="https://knowledge.bsigroup.com/products/specifications-for-installations-inside-buildings-conveying-water-for-human-consumption-general/standard">BS EN 806 </a>and <a href="https://knowledge.bsigroup.com/products/guide-to-the-design-installation-testing-and-maintenance-of-services-supplying-water-for-domestic-use-within-buildings-and-their-curtilages-complementary-guidance-to-bs-en-807/tracked-changes">BS 8558</a></p><p> </p><p><strong>Please note:</strong></p><p>All water fittings should be resistant to corrosion. In the case of mechanical backflow prevention devices and metallic fittings which are not going to be readily accessible, in addition to being corrosion resistant these should be manufactured from materials which are not susceptible to dezincification. For example, gunmetal or CR brass.</p><p>As non-metallic pipe and fittings can be affected by sunlight and/or allow ingress of light, which is known to promote the growth of algae, consideration should be given to whether protective measures to exclude light are necessary.</p><p>Adhesive joints are not acceptable below ground.</p><p> </p><h1 id="topics">FAQs</h1><p><br></p>

Regulations & Byelaws which apply include but are not limited to:

Regulation 4 England & Wales
Regulation 4 Northern Ireland
Byelaw 4 Scotland
Regulation 3 England & Wales
Regulation 3 Northern Ireland
Byelaw 3 Scotland
Regulation 5 England & Wales
Regulation 5 Northern Ireland
Byelaw 5 Scotland
Schedule 2 paragraph 2
Schedule 2 paragraph 3
Schedule 2 paragraph 4
Schedule 2 paragraph 5
Schedule 2 paragraph 6
Schedule 2 paragraph 7
Schedule 2 paragraph 8
Schedule 2 paragraph 10
Schedule 2 paragraph 11
Schedule 2 paragraph 14
Schedule 2 paragraph 15
Schedule 2 paragraph 16
Schedule 2 paragraph 25
Schedule 2 paragraph 26
Schedule 2 paragraph 27
Schedule 2 paragraph 28
Schedule 2 paragraph 29
Schedule 2 paragraph 30
Schedule 2 paragraph 31

Guidance

Regulation 5 England & Wales
Regulation 5 Northern Ireland
Byelaw 5 Scotland
Schedule 2 paragraph 2
Schedule 2 paragraph 3
Schedule 2 paragraph 4
Schedule 2 paragraph 7
Schedule 2 paragraph 8
Schedule 2 paragraph 11
Schedule 3 paragraph 14
Schedule 2 paragraph 15
Schedule 2 paragraph 26
Schedule 2 paragraph 27

Publications

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