05 - Water

Assessment of multiple buildings within a single BREEAM assessment - KBCN1836

Ene01, Ene02 and Wat01, which use area-weighted performance scales, must be assessed using the methodology set out below where multiple buildings are included within the scope of a single BREEAM assessment, including where: • the Similar Buildings approach is applied, in accordance with Section 4 of GN20; or • Separate buildings with a single overarching function are located on the same site, in accordance with Section 6 of GN20 (e.g. a principal building with one or more ancillary or supporting buildings). Ene01 For UK NC projects, energy models (BRUKL files) must be uploaded for each building included within the assessment. For International NC projects, the assessor must enter floor area-weighted average values for the relevant energy performance metrics for both the actual building(s) and the reference building(s), covering all buildings and applicable building uses included in the assessment. Ene02 All buildings included within the assessment must be modelled in accordance with the methodology. The energy performance score must be calculated using floor area-weighted metrics covering all buildings, and compared against a benchmark derived from a floor area weighted average of all building types included within the assessment. Wat01 For Wat01, the assessor must enter details for all water-using components across all buildings included within the assessment. The Wat01 benchmark is determined using a floor area-weighted occupancy by building type, covering all buildings within scope of the BREEAM assessment.

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Leak detection – compliance principle – alternative technologies - KBCN1566

Where it can be demonstrated that alternative water leak detection 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 alternative solutions are currently recognised:

• Smart leak detection systems that are based on 'self-learning' (machine learning) to determine normal water use patterns are an acceptable alternative to systems that require manual pre-sets or manual programming.

06-Jul-2026 - Title updated for consistency. Scheme applicability updated. Principle also applied to refrigerant leak detection.

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Leak detection – using a BMS - KBCN0439

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

07 Feb 2022 - Applicability to BIU USA Commercial V6 confirmed

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