04 - Water - BREEAM Knowledge Base

Automatic control for basin taps – Multi-residential long-term stay assets - KBCN1587

Only taps that are specifically used in staff, communal or public hand washing basins are required to meet the automatic control requirements set out in Criterion 1. These requirements do not apply to residents’ private sanitary facilities in residential long-term stay assets.

Erratum – up to V6.0.0 – blackwater in assessment scope - KBCN1567

Scope The scope of this issue includes blackwater. Criterion 4 should include d) blackwater harvesting. Definitions The definition for 'blackwater' is missing from this issue, and the definition for 'greywater' is inconsistent with other issues in the manual. The following text will be updated in the next revision of the manual: Blackwater - Wastewater that has been discharged from kitchen and utility sinks, urinals and toilets within the asset. Greywater - Water that has been discharged from all sources other than kitchen and sewage within the asset.

Fire hydrants and sprinklers – Leak detection - KBCN0680

Where it is confirmed by an appropriate project team member that it is not possible to fully meet the leak detection criteria for fire hydrants or sprinklers, an alternative approach can be implemented for these systems. This must demonstrably meet the aim of the issue by detecting and alerting the building management to major water leaks. Previous guidance - superseded on 30 May 2024 To meet BREEAM compliance, emergency systems such as fire hydrants and sprinklers need also to be covered by a leak detection system. The leak detection system must cover all mains water supply between and within the building and the ‘site boundary'.

11 Sep 2024 - Applicability to BIU V6 confirmed - QN-75509-C8H8V1
30 May 2024 - New guidance introduced to clarify that BREEAM compliance should not compromise the operation of building safety-critical systems. Applicability to NC V6 standards confirmed.

Flow control devices – residential accommodation - KBCN0415

The credit for the specification of flow control devices in WC areas or facilities does not apply to ensuite facilities in residential areas, e.g. ensuite facilities in individual private bedrooms and a single bathroom for a collection of individual private bedrooms in halls of residence, key worker accommodation or sheltered accommodation. The credit and criteria are however applicable to buildings which have guest bedrooms with ensuite facilities, e.g. hotel rooms, and communal WC areas or facilities, e.g. communal WC facilities in hotels or hostels and care homes. In accommodation where occupancy is long-term and there is a sense of ownership of the space, flow control does not need to be assessed as the occupants are likely to detect and report leaks.

26 Oct 2023 - Applicability to BIU V6 Commercial confirmed

Flow control devices – Use of devices on individual sanitary fittings - KBCN1550

The intent of the requirement for flow control devices is to minimise the impact of undetected wastage and leaks from sanitary fittings and supply pipework. The use of flow control devices on individual sanitary fittings alone does not, therefore, fully meet this aim.

Flow control devices for multiple blocks - KBCN1186

The criteria are set to encourage isolation of the water supply to each WC block when it is not being used. If a single flow control device, for example one programmed time controller, is adequate to switch the water on at predetermined times that suit the usage patterns of more than one WC blocks or facilities, this can be used to demonstrate compliance. Please note that if only one timed controller is used for a large area/number of facilities, the assessor must justify that this is appropriate to the usage patterns within the building and confirm that multiple timers would be redundant (i.e. they would all be set to the same time). Consideration should be given of any facilities that may be open longer than others, requiring these timers to be programmed differently in different areas. As long as the aim of the credit (‘to reduce the impact of water leaks that may otherwise go undetected’) can be achieved through the specification of an appropriate number of flow control devices, the credit may still be achieved if timers cover more than one WC area/facility to prevent minor water leaks.

14 Apr 2023 - Applicability to BIU V6 Commercial confirmed.

Leak detection – using a BMS - KBCN0439

A BMS can be used for leak detection purposes if it can be demonstrated that its integrated or add-on features meet all the requirements for a leak detection system.

07 Feb 2022 - Applicability to BIU V6C confirmed

Process water to offset potable water demand - KBCN0586

Where it is demonstrated that it is safe to do so, process water resulting from the building under assessment, can be considered for off-setting potable water demand from components that would otherwise be supplied using potable water, when in line with the criteria requirements for greywater systems. Process water resulting from the building under assessment can be considered as a form of greywater for the purposes of off-setting potable water demand.

21 Dec 2021 Additional wording added, requiring it to be demonstrated that process water is safe to use and KBCN applied to BIU standards.

Shower with multiple shower heads - KBCN0855

To calculate the water use of a shower with more than one shower head, one of the following should be done:

If all of the shower heads can be turned on at once, the flow rates should be added up.
If the shower heads can only be used one at a time, the highest flow rate should be used

22 Feb 2024 - Applied to BIU, BREEAM NC and RFO standards

Sub-metering – Requirements for water-consuming plant/building areas or no additional monitoring benefit - KBCN1637

Significant water demand: The following water uses are deemed to be significant:

Swimming pools and their associated changing facilities (toilets, showers etc.)
On sites with multiple units or buildings, e.g. shopping centres, apartment blocks, industrial units, retail parks etc. separate sub-meters are fitted on the water supply to the following areas (where present): a. For Residential buildings with multiple dwellings and Residential Institutions with multiple with self-contained dwellings, each dwelling counts as a significant water use. b. Common areas (e.g., covering the supply to toilet blocks). c. Service areas (covering the supply to outlets within storage, delivery, waste disposal areas etc.). d. Ancillary or separate buildings to the main development with a water supply.
Laboratories: in any building with a laboratory (or containing laboratories), a separate water meter is fitted on the water supply to any process or cooling loop for plumbed-in laboratory process equipment.

All water consuming systems or building areas that are expected to account for more than 10% of the buildings total water demand must be considered when determining significant water uses. No additional monitoring benefit: Sub metering is not required where the project team confirms there will be no additional monitoring benefit resulting from their installation. Examples include:

Where a building has only one or two small sources of water demand (e.g. an office with only sanitary fittings and a small kitchen facilities).
Where the building has two sources of water demand, one significantly larger than the other, and the water consumption for the larger demand is likely to mask the smaller demand (e.g. where there is a larger water demand from a changing area complete with showers and toilets, and the only other water demand is for toilet facilities).

Where the asset is targeting answer E (sub-metering) and:

Can show that there is no additional monitoring benefit from installing sub-meters in line with criterion 5 and,
Has met the requirements for answers C (site metering) and D (building metering),

then the 6 credits for answer E are awarded by default.

16 October 2024: Updated to include examples of water-consuming plant/building areas and also where no additional monitoring benefit.

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.

Using water from natural underground sources to offset water consumption - KBCN00094

Water from natural underground sources (for instance aquifer water accessed via boreholes) cannot be used to offset:

NC / RFO: potable water consumption.
IU: utility supplied water consumption.

A significant amount of water used for public consumption is already drawn from aquifers. Private boreholes may be drawing water from the same sources as public utility companies.

27-Mar-2024 - Title and text updated to broaden definition. Scheme applicability updated.

Washer dryers - KBCN0699

Where a washer dryer is specified, the water consumption figure for the wash and dry cycle should be used. The drying cycle of a washer dryer is taken into account because it usually uses water during this drying process (e.g. for cooling during the drying cycle) and in some cases, this water usage can be significant.

18-Nov-2022 - Updated to apply to BREEAM In-Use Version 6

Washing machines and dishwashers – Water consumption data - KBCN1571

The water consumption data used to demonstrate compliance may be based on the lowest full wash cycle (i.e. not a pre-wash cycle, for example).

In-Use / BIU International Commercial V6 / Part 1 /

04 - Water