WAT 02 - Water Monitoring

Areas consuming less than 10% of the building’s total water demand - KBCN0662

Where water-consuming plants or building areas are required to be sub-metered as a minimum, the requirements apply even if those plant/elements consume less than 10% of the building's total water demand.

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Domestic hot water supplied by a circulation loop - KBCN1017

Where a circulation loop is used on the domestic hot water supply, it is acceptable to only sub-meter the cold water supply. Sub-metering such systems may be impractical and the occupant can use the cold water meter readings as a proxy for overall water usage in relevant areas.

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Majority of water demand from rainwater harvesting - KBCN0860

If the majority of water use is supplied by sources other than mains or private water, for example rainwater harvesting, and this use will be monitored, additional metering of the smaller water demand that is masked by the larger demand is not necessary.

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Metering recycled water - KBCN0658

Water-consuming plant or building areas consuming 10% or more of the building’s total water demand need to be sub-metered. This applies to recycled water, such as rainwater, grey water or process water as well as mains water. The aim of the Issue is to encourage reductions in water consumption, which is beneficial, regardless of its source. Monitoring the use of recycled water, may also help to reinforce the benefits of doing so and encourage further reductions.

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Self-contained dwellings or units with individual utility meters - KBCN0199

Where self-contained dwellings or units covered by the assessment have their own individual energy supply and utility meter (e.g. water, gas or electricity), this supply can be excluded from the scope of the issue. All shared energy supplies and common areas under the responsibility of building management are still included in the assessment. For example, if self-contained flats in an assisted living development have individual gas supplies with their own utility meter, this supply will be excluded from the assessment. However, the lighting and small power comes from a shared distribution board on each floor, in which case this shared supply will need to be sub-metered in accordance with the criteria. This same principle applies to scenarios involving speculative industrial or retail units with capped services, where these units have their own utility meter.

12/09/2018 Applicable to Water Monitoring Issue where appropriate
27/09/2017 The word 'units' added to include a wider range of scenarios falling under this principle.
17/06/2022 Added other industrial / retail situations for further clarity on the applicability of this KBCN.

 

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Sub-metering technologies – Compliance Principle - KBCN1561

Where it can be demonstrated that alternative sub-metering technologies can meet or exceed the capabilities of systems set out in the BREEAM guidance, subject to approval, these can also be considered compliant. It is the role of the Assessor and the project team to provide evidence and justification in a compliance principle query (see KBCN1555). The following metering standards or technologies are currently recognised as alternatives to pulsed output meters:

• M-bus. I.e. systems that comply with the EN 13757 series of standards. Also includes systems complying with the OMS (Open Metering System) standards.

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Water monitoring when only part of a building is under assessment - KBCN0548

When only part of the building is under assessment, there are two cases for achieving compliance with the requirement to specify a water meter on the mains water supply of the building: If the whole building is under the same tenancy or ownership and management, then a meter monitoring the entire building is acceptable. However, if the floors subject to assessment are separately tenanted, then a meter at the point of entry to the assessed areas is required. Assessed areas have to be monitored separately for water consumption when only part of the building falls within the scope of assessment and where the assessed areas are separately tenanted.

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