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Wat 01 Water consumption

Number of credits available Minimum standards
5 Yes

Aim

To reduce the consumption of potable water for sanitary use in new buildings from all sources through the use of water efficient components and water recycling systems.

Assessment Criteria

The following is required to demonstrate compliance for:

Up to five credits

  1. An assessment of the efficiency of the building’s domestic water consuming components is undertaken using the BREEAM Wat 01 calculator.
  2. The water consumption (litres/person/day) for the assessed building is compared against a baseline performance and BREEAM credits awarded as follows:
% improvement No. of BREEAM credits
12.5% 1
25% 2
40% 3
50% 4
55% 5
65% Exemplary performance

Note: for some building types usage data may not be available. In such cases an alternative elemental based approach to compliance should be used to award credits (refer to Compliance notes and Additional Information section).

  1. The efficiency of the following ‘domestic scale’ water consuming components must be included in the calculation (where specified):
    1. WCs
    2. Urinals
    3. Taps (wash hand basins and where specified kitchen taps and waste disposal unit)
    4. Showers
    5. Baths
    6. Dishwashers (domestic and commercial sized)
    7. Washing machine (domestic and commercial/industrial sized)

The BREEAM Wat 01 calculator defines the building types and activity areas for which the above components must be assessed.

  1. Where a greywater and/or rainwater system is specified, its yield (l/person/day) can be used to off-set non potable water demand from components that would otherwise be supplied using potable water.
  2. Any greywater systems must be specified and installed in compliance with BS8525-1:2010 Greywater Systems - Part 1 Code of Practice1BS8525-1:2010, Greywater systems – Part 1 code of practice, BSi, 2010. Any rainwater systems must be specified and installed in compliance with BS8515:2009 Rainwater Harvesting Systems - Code of practice2BS8515:2009, Rainwater harvesting systems – Code of practice, BSi, 2009.
  3. Report the total net water consumption in m3/person/yr, via the BREEAM scoring and reporting tool (where total net water consumption can be modelled by the BREEAM Wat 01 calculator for the assessed building type).
  4. Healthcare and prison buildings: refer to the relevant Compliance note for additional criteria regarding the specification of particular micro-component controls.

Compliance Notes

Ref

Terms

Description

CN1 

Scope of the BREEAM Wat 01 Methodology for New Non Domestic Buildings. See criteria 1,2 & 3

The BREEAM Wat 01 calculator determines a figure for whole building water consumption from domestic scale components. This figure is derived using the actual component specification and default component usage factors for a range of building users/types.

The methodology is applicable to the majority of new non-domestic building types assessed using this BREEAM Scheme. There may however be some instances in which data on the usage patterns for certain types of buildings/users, are not available (or those used in the methodology are not appropriate).

Where this is the case, it will not be possible to calculate the whole building water consumption and percentage improvement level. In such instances, compliance and the number of credits achieved will need to be assessed using an alternative, elemental approach i.e. comparing the buildings component specification with minimum levels of performance and awarding BREEAM credits accordingly.

Details of the alternative approach and how to apply it are provided in the Additional Information section for this issue (see below).

Please also refer to the Compliance note below where the building is a mixture of different building types covered by the Water Efficiency Methodology.

CN2 

Domestic scale water consuming components data. See criterion 1 & 3

Water consumption figures will need to be collected from manufacturers’ product information to determine the consumption of each type and specification of domestic scale water consuming component required, as follows:

WCs: actual maximum or, where dual flush, effective flush volume in litres/use

Urinals: Flush volume in litres/use for single use flush urinals. For cistern fed systems, the flushing frequency/hour and cistern capacity in litres.

Taps: Flow rate of each tap, at full flow rate in litres per minute measured at a dynamic pressure of 3±0.2 bar (0.3±0.02 MPa) for high pressure (Type 1) taps, or at a dynamic pressure of 0.1±0.02 bar (0.01±0.002 MPa) for low pressure (Type 2) taps (BS EN 200:2008, sanitary tapware, single taps and combination taps for supply systems of type 1 and 2. General technical specifications) including any reductions achieved with flow restrictions.

Showers: Flow rate of each shower at the outlet using cold water (T 30˚ C), in litres per minute measured at a dynamic pressure of 3±0.2 bar (0.3±0.02 MPa) for high pressure (Type 1) supply systems, or at a dynamic pressure of 0.1±0.05 bar (0.01±0.005 MPa) for low pressure (Type 2) supply systems (BS EN 1112:2008, Sanitary tapware. Shower outlets for sanitary tapware for water supply systems type 1 and 2. General technical specifications).

Kitchen taps: Maximum flow rate litres/min.

Baths: capacity to overflow in litres. Taps on baths should not be included in the calculation, as the water consumption from bath taps is taken account of in the use factor for baths. The calculation of water consumption for baths will assume 40% of the capacity to the overflow. This is to reflect that a) users tend not to fill the bath to overflow and b) the displacement affect the user has on the actual volume of water required for a bath.

Dishwasher: litres/cycle for domestic applications and/or appliances or litres/rack for commercial applications and/or appliances.

Washing machine: litres/use for domestic applications and/or appliances or litres/kg for commercial applications and/or appliances e.g. in hotels.

Waste disposal unit: flow rate in litres/minute.

CN3 

Greywater and rainwater system data. See criteria 4 & 5

The following information is required where a greywater and/or rainwater system is specified:

Rainwater: in accordance with BS8515 ‘intermediate approach’ :

  1. Collection area (m2)
  2. Yield co-efficient (%)
  3. Hydraulic filter efficiency (%)
  4. Rainfall (average mm/year)

Rainwater: in accordance with BS8515:2009 Rainwater Harvesting Systems - Code of Practice ‘detailed approach’ :

  1. Daily rainfall collection (litres)

Greywater: in accordance with BS8525-1:2010 Greywater Systems - Part 1 Code of Practice :

  1. Manufacturer or system designer details.
  2. The percentage volume of waste water collected (and re-used) from the following (where relevant); wash hand basins, showers, kitchen basins, dishwashers, baths, washing machines and sources of waste water from non domestic components.

CN4 

Multiple specifications for the same water consuming component . See criterion 6

Where multiple fittings of the same component are specified, with various different flow rates, the flow rates for each type of fitting will need to be collected by the assessor and entered into the 'Average flow rate calculator worksheet' (contained within the Wat01 calculator) to determine the average flow rate for the component. This figure is then entered in to the relevant section of the Wat01 calculator.

CN5 

Using greywater and rainwater systems to off-set performance efficiency of components. See criteria 4 & 5

Where greywater and/or rainwater systems are specified there is a minimum level of component efficiency that must be achieved to award 4 or 5 BREEAM credits and the exemplary level credit. This is to avoid awarding a higher number of BREEAM credits where performance from less efficient fittings is off-set by the specification of a greywater and/or rainwater collection system. The intention being to ensure demand reduction is prioritised before off-setting consumption.

Where a greywater/rainwater system is specified/installed, the component specification must achieve a percentage reduction in water consumption (over the baseline specification) equivalent to that required for 2 credits i.e. a 25% improvement.

Where this level is achieved, all of the total water demand met by greywater/rainwater sources can contribute to the overall percentage improvement required to achieve BREEAM credits. If it is not achieved, the percentage of greywater/rainwater allowable will be equivalent to the percentage improvement in water consumption achieved for the component specification (i.e. percentage improvement on baseline performance). For example, if only a 20% improvement is achieved, and therefore the building is not meeting the 25% requirement, then only 20% of the water demand met via greywater/rainwater sources can be used to off-set water consumption from the microcomponents.

This minimum requirement does not apply where only 1, 2 or 3 credits are sought or where no greywater/rainwater system is specified i.e. percentage improvement is based solely on the water efficiency of the microcomponent specification. BRE Global may allow some exemptions to this rule in instances where a particular fitting type requires a high flow rate due to specialised end-user requirements, and its specification prevents compliance with the 25% improvement level.

CN6 

Other permissible component demand for non potable water. See criteria 3,4 & 5

The focus of this BREEAM issue is the performance of the building's permanent domestic scale water consuming components. Where a greywater or rainwater system is specified, the yield from the system should be prioritised for such uses i.e. WC/Urinal flushing. However, where the building demonstrates that it has other consistent (i.e. daily) and equivalent levels of non potable water demand, and such demands are intrinsic to the building’s operation, then it is permissible for the demand from these non domestic uses to be counted i.e. the demand for rainwater/greywater yield from such systems/components can be used as well as, or instead of non potable water demand from the buildings WC/Urinal components.

Examples of consistent and intrinsic demands could include laundry use in hotels/ multi-residential developments or horticultural uses in garden centres, botanical gardens and golf courses . Demand for general landscaping and ornamental planting irrigation are not considered as equivalent/intrinsic by BREEAM.

CN7 

Other permissible source of non potable water. See criteria 3,4 & 5 The methodology allows for the collection and recycling of non potable water from the relevant components listed in the criteria i.e. taps, showers, baths and dishwashers/washing machines. In addition, where non potable water is collected from a non domestic component/source that is intrinsic to the building, then the amount collected can be accounted for in the methodology. This could include for example wastewater from active hygiene flushing, i.e. a regular hygiene flushing programme to minimize poor water quality in a potable cold or hot water system. In order for the method to account for this total, the design team will need to confirm to the assessor the yield from the component/system (in litres) and the frequency of that yield (in days) i.e. if once a week then frequency would be 7 days.

CN8 

Building is a mixture of different functional areasSee criterion 1

For the majority of buildings using the standard Wat 01, the BREEAM Wat 01 calculator defines the building type and range of different water consuming activity areas within that building; for example, a retail development with sales area and goods storage or an office that includes a canteen and gym. However, where permitted to conduct a single assessment of a building/development which consists of a diverse mix of activity areas/building types, all of which can be assessed separately within the calculator, the following applies:

Determine the building’s total water consumption performance by carrying out separate assessments for each relevant activity area/building type. On completion of each assessment, the assessor will need to determine the percentage improvement as follows:

overal improvement in percentage equals hundred times one minus a fraction between THE sum from one to n of the modelled net water consumption times the total default occupancy rate AND THE sum from one to n of the modelled baseline water consumption times the total default occupancy rate

Where:

I = Overall improvement (%)
TnAct = the modelled net water consumption (L/person/day) for each building type
TnBase = the modelled baseline water consumption for the corresponding building type
TnOcc = the total default occupancy rate for the corresponding building type.

Where greywater/rainwater systems are specified, the assessor should take care to avoid unintended double counting of the yield from such systems and using it to off-set demand for each activity area/building type.

This compliance note is likely to become more relevant as the BREEAM Wat01 calculator develops to include more building types within the standard Wat01 method.

CN9 

Fixed water use. See criterion 6 The BREEAM water efficiency calculation includes an allowance for fixed water use. This includes water consumption for vessel filling (for building user drinking water), cleaning in kitchens and food preparation in buildings with a catering facility. Fixed uses are included to provide greater accuracy in reporting of the building’s overall estimated water consumption. As these uses are fixed for both the actual and baseline building models, their totals do not influence the achievement of BREEAM credits.

CN10 

Shell only

If a water supply is provided to tenanted areas of the building, but sanitary components will be specified and fitted by future building tenants, then the following options are available to define the efficiency of flow rates for components in the shell only (tenanted) areas of the building:

  1. Option 1 – use of a tenancy lease agreement between the developer and tenant(s) which specifies a minimum acceptable level of water efficiency for specified components.
  2. Option 2 - N/A
  3. Option 3 – whereby the tenant confirms (in writing or via their fit out specification) the efficiency of fittings that will be specified/installed.

Alternatively, fittings compliant with the BREEAM baseline level can be used for the purpose of determining the level of performance for the building (see Additional Information section for further detail on the baseline level).

CN11 

Components in healthcare facilities. See criterion 7

In addition to meeting an overall percentage improvement level, the flushing control for each WC/urinal in a healthcare facility must be suitable for operation by patients with frail or infirm hands or activated by electronic sensors.

Components in clinical areas can be exempt from the calculation. For the purpose of this compliance note ‘clinical areas’ refers to all areas where a scrub-up trough, clinical sink or clinical basin is installed. This is not an exhaustive list and guidance should always be sought from the appropriate professional, such as a Health Authorities Infection control officer or a client infection control representative or equivalent, to ascertain areas of exemption specific to infection control and other considerations.

Although exempt, HTM07-04 contains guidance on water savings from medical related activities. Furthermore, in some cases, the use of water-efficient fittings and appliances may not be appropriate to the needs of the patient, and inappropriate specification may adversely affect the incidence and propagation of infections. In such instances, the assessor will need to confirm with BRE Global the exemption of components from the relevant building areas. The design team should also consult NHS guidelines concerning appropriate selection of sanitary fittings and fixtures and the control of legionella.

.

CN12 

Components in prison cells on HM Prison developments. See criterion 7

In addition to meeting an overall percentage improvement level, the following requirements apply:

Where sanitary components are specified within a prison cell, a volume controller must be specified on the individual fittings or water supply to each cell.

A volume controller is an automatic control device to turn off the water supply once the maximum preset volume is reached within a defined period.

CN13 

Multi-residential developments with CSH assessed dwellings. See criterion 1 The number of credits achieved for Wat 1 of a Code for Sustainable Homes assessment cannot be directly used for this issue due to the differences in the calculation methodology.

CN14 

No fittings present

Where a project under assessment contains none of the specified components, the performance specification for components provided in facilities in an adjacent and accessible building must be used in the calculation, i.e. those facilities most likely to be used by the occupants and visitors of the assessed building.

This rule also applies where a project under assessment consists solely of an extension to an existing building, i.e. where the extended building contains no new sanitary facilities because there are facilities present within the existing building.

Schedule of Evidence

Ref Design stage
Post-construction stage
All

Completed copy of the BREEAM Wat 01 calculator

Relevant section/clauses of the building specification/ design drawings confirming technical details of;

  1. Sanitary components
  2. Rainwater and greywater collection system

OR where detailed documentary evidence is not available at this stage;

Completed BREEAM Wat 01 calculator

A letter of instruction to a contractor/supplier or a formal letter from the developer giving a specific undertaking, providing sufficient information to allow the water calculations to be completed.

Where Post Construction Stage assessment only, provide a completed copy of the BREEAM Wat 01 calculator and detailed documentary evidence (as listed for Design Stage) representing the building as built OR

Written confirmation from the developer that the appliances/fittings have been installed as specified for the Design Stage or Assessor site inspection report and photographic evidence confirming installation of components in accordance with a compliant specification OR

Where only a letter of instruction was provided with calculations at Design Stage, provide revised calculations and detailed documentary evidence (as listed for Design Stage) representing the building as built OR

Where different from Design Stage, provide revised BREEAM Wat 01 calculator and detailed documentary evidence (as listed for Design Stage) representing the building as built.

Additional Information

Relevant definitions

BREEAM Wat 01 calculator for New Non Domestic Buildings
The BREEAM Wat 01 calculator is a method for the assessment of water efficiency in most common types of new non domestic buildings. The calculator assesses the contribution that each internal domestic scale water consuming component (as listed in the criteria) has on whole building water consumption).
The calculator and accompanying guidance on its application is available separately from this Scheme Document.
Please note; the calculator is a compliance tool and not a design tool for water demand and drainage systems. The tool uses default usage and occupancy rates to provide a benchmark of the typical consumption given the specified fittings (in litres/person/day and m3/person/year) and their impact on the buildings overall water efficiency. Due to the impacts and differences of actual user behaviour and occupancy rates the results of the method will not reflect directly the actual water use during building operation. The results from the methodology should, therefore, not be used for the purpose of comparison with or prediction of actual water consumption from a non domestic building.
Domestic scale components
Domestic scale components include water consumed (potable and non potable) by internal building components including kitchen taps, wash hand basin taps, baths, shower and dishwasher, WCs, urinals, washing machines and waste disposal units.
Effective flush volume
Effective flush volume is the volume of water needed to clear the toilet pan and transport any contents far enough to avoid blocking the drain. The effective flush volume of a single flush WC is the volume of water used for one flush.
The effective flush volume of a dual flush WC is the ratio of full flush to reduced flush. This is taken to be one full flush for every three reduced flushes for non-domestic buildings and one full flush for every two reduced flushes in domestic (residential) buildings/areas. The effective flush volume can therefore be calculated as follows, using a 6/4 litre dual flush volume WC as an example:
The differing ratio between non-domestic and domestic buildings reflects the different patterns of user behaviour between these building types.
Greywater recycling
The appropriate collection, treatment and storage of domestic wastewater (which is defined as that discharged from kitchens, baths/showers, laundry rooms and similar) to meet a non potable water demand in the building e.g. WC flushing, or other permissible non potable use on the site of the assessed building.
Potable water
Water suitable for human consumption that meets the requirements of Section 67 (Standards of Wholesomeness) of the Water Industry Act 19913Great Britain, The Water Industry Act 1991. London: The Stationery Office. Also referred to as wholesome water.
Non potable water
Any water other than potable water, also referred to as unwholesome water (BS8525, see references).
Rainwater recycling
The appropriate collection and storage of rainwater run-off from hard outdoor surfaces to meet a non potable water demand in the building e.g. WC flushing, or other permissible non potable use on the site of the assessed building.
Clinical areas
Refer to BREEAM issue Hea 01 Visual comfort.

Checklists and Tables

Table - 17 outlines the standards, by component type, used to define the performance levels set in BREEAM. These defined levels of efficiency have been steered by a range of published sources of information (see references4AECB Water Standards: Delivering buildings with excellent water and energy performance, vol 2 The water standards, technical background report (version 1), Grant, Thorton, AECB, 2009.BNWAT22: Domestic water consumption in domestic and non-domestic properties (version 1.1). Market Transformation Programme, 2007.BNWAT07: Baths - water efficiency performance tests (version 2.0). Market Transformation Programme, 2007.BNWAT23: Reliability of information on water consumption of appliances (version 1), Market Transformation Programme, 2007.BS6465-3:2006, Sanitary installations – Part 3: Code of practice for the selection, installation and maintenance of sanitary and associated appliances. BSi, 2006.CIRIA W10, Key Performance Indicators for water use in hotel, Rachel Waggett and Catherine Arotsky, CIRIA, 2006.CIRIA W11, Key Performance Indicators for water use in offices, Waggett, Arotsky, CIRIA, 2006.Conserving water in buildings, a practical guide. Environment Agency, 2007.Enhanced Capital Allowance Water Technology List criteria: www.eca-water.gov.ukReport by Entec UK Ltd for CLG: Research to Assess the Costs and Benefits of Improvements to the Water Efficiency of New Non-household Buildings, Final Report, Oct 2009.SD129: Certification and Listing of Low Flush WC appliances. BRE Global, 2008.SD174: Certification and Listing of Water Efficient Terminal Fittings. BRE Global, 2008.SD175: Certification and Listing of Water Efficient Baths. BRE Global, 2008.The Building Regulations 2000, Part G: Sanitation, hot water safety and water efficiency (2010 edition). HM Government.Waterwise: www.waterwise.org.ukWater Efficiency Calculator for New Dwellings. Communities and Local Government, 2009.Water efficient product labelling scheme: www.water-efficiencylabel.org.ukWater Supply (water fittings) Regulations 1999, DEFRA.Sustainable Products 2006: Policy Analysis and Projections, Market Transformation Programme, 2006.Water UK - Macerators, the impact on sewers: www.water.org.uk/home/policy/positions/waste-macerators-position-paperWater Efficient Buildings, water and planning, guidance for planners http://www.water-efficient-buildings.org.uk/) and therefore reflect robust levels of typical, good, best and exemplary practice.

Table - 17: Water efficient consumption levels by component type

Component Performance Levels
  Base 1 2 3 4 5 Unit
WC 6 5 4.5 4 3.75 3 Effective flush volume (litres)
Wash hand basin taps 12 9 7.50 4.50 3.75 3 litres/min
Showers 14 10 8 6 4 3.50 litres/min
Baths 200 180 160 140 120 100 litres
Urinal
(2 or more urinals)
7.50 6 3 1.50 0.75 0 litres/bowl/hour
Urinal
(1 urinal only)
10 8 4 2 1 0 litres/bowl/hour
Greywater/rainwater system 0% 0% 0% 25% 50% 75% % of WC/urinal flushing demand met using recycled non potable water
Kitchen tap:
kitchenette
12 10 7.50 5 5 5 litres/min
Kitchen taps:
restaurant (pre-rinse nozzles only)
10.30 9 8.30 7.30 6.30 6 litres/min
Domestic sized dishwashers 17 13 13 12 11 10 litres/cycle
Domestic sized washing machines 90 60 50 40 35 30 litres/use
Waste disposal unit 17 17 0 0 0 0 litres/min
Commercial sized dishwashers 8 7 6 5 4 3 litres/rack
Commercial/
Industrial sized washing machines
14 12 10 7.50 5 4.50 litres/kg

Please note that specifying components for a building in accordance with the above levels will result, in most cases, in the corresponding number of BREEAM credits being achieved. However, please bear in mind that the component specifications above are thresholds between each level. Therefore caution should be taken when defining a component specification for a BREEAM assessed building using exactly the same levels as the threshold levels. It is recommended that, where Wat 01 BREEAM credits are being targeted, the performance of a particular building’s component specification is verified using the BREEAM Wat 01 calculator before committing to a particular specification and ordering/installing components. This will provide greater assurance that the component specification achieves the targeted number of BREEAM credits.

As the methodology and BREEAM credits for water efficiency compare the buildings modelled water consumption performance against the performance of a baseline specification for the same component types, where a component type is not specified it is not accounted for in the methodology i.e. the component is excluded from both the proposed and baseline building. Therefore no benefit is gained in terms of BREEAM performance, which is the % improvement over the baseline building, by deciding not to specify a particular component. However, the methodology will reflect the reduction in overall water consumption (litres/person/day) for the building, as a result of not specifying a particular component.

Calculation procedures

A non domestic building’s water-efficient performance is determined using the BREEAM Wat 01 calculator in one of two ways, using either the standard approach (common building types) or alternative (other building type) approach. Each approach is summarised below .

Standard Wat01 method

The standard BREEAM method determines water efficiency (measured in l/person/day and m3/person/yr) for a building based on the buildings actual component specification and default usage patterns for the building type and its activity areas. This modelled output is compared with the same output for a baseline component specification and the percentage improvement used to determine the number of BREEAM credits achieved.

The baseline component specification is equivalent to the water efficiency of industry standard components (see Table - 17), steered by the minimum levels required by the Water Supply (Water Fittings) Regulations . The BREEAM percentage improvement benchmarks have then been determined based on progressively more efficient standards for water consuming components and, for the higher levels of performance, the specification of greywater and rainwater systems.

The standard approach is the default method for calculating water efficiency of a BREEAM assessed building and is that used for most of the common building types, where usage data is available. For buildings types where usage data is not available, and therefore the standard approach of determining performance cannot be used, an alternative approach to compliance must be used (described below). Refer to the BREEAM Wat 01 calculator for the current list of building types which can be assessed using the standard approach.

Alternative Wat01 method

Where it is not possible to use the standard approach to determine the buildings water consumption total (litres/person/day)the assessment can be completed on an elemental basis, as follows:

  1. Using the list of applicable domestic scale water consuming components (see criterion 3), determine those that are specified/present in the assessed building.
  2. Compare the actual specification for each component type with the table of water efficient consumption levels by component type (Table - 17) to determine the level of performance for each type. Note that the volumes quoted are maximums for that level and the % WC/urinal flushing demand is a minimum for that level.
  3. Define each component’s level of performance in the other building type calculator worksheet of the BREEAM Wat 01 calculator.
    1. For the alternative approach, the calculator applies a building type specific weighting to each component level to reflect its ‘in-use’ consumption relative to the other components present. A component with high ‘in-use’ water consumption therefore has a larger weighting than one with lower ‘in-use’ consumption and contributes relatively more or less to the building’s overall level of performance.
    2. The weightings are derived from data on actual water consumption per day from non domestic buildings, sourced from BNWAT225BNWAT22: Domestic water consumption in domestic and non-domestic properties (version 1.1). Market Transformation Programme, 2007. They can be found in the BREEAM Wat 01 calculator.
  4. Based upon the performance categorisation of each component type and the component weighting, the calculator will determine an overall component level of performance and award the relevant number of BREEAM credits as follows:
  Greywater/rainwater level achieved
Overall Component level - 4 5
Baseline 0 credits 1 credit 2 credits
Level 1 1 credit 2 credits 3 credits
Level 2 2 credits 3 credits 4 credits
Level 3 or 4 3 credits 4 credits 5 credits
Level 5 4 credits 5 credits

Note:

  1. An innovation credit for exemplary level performance can be awarded where the component specification achieves level 5 and >95% of WC/urinal flushing demand is met using recycled non potable water.
  2. Due to the use of the weightings, the overall component level achieved will not necessarily be a whole number e.g component level 4. Where this is the case the methodology will always round down to the nearest component level and therefore BREEAM credit(s) level, e.g. if the component specification achieved is 3.6 credits, the actual number of credits awarded is 3 credits (the methodology will not round up to 4 credits because the performance specification for 4 credits has not been achieved).
  3. Where the assessed building development has multiple specifications for the same water consuming component type, the number of fittings and component level achieved for each specification can be entered in the Other Building Type calculator. Using this information, the calculator will determine the building’s aggregated performance level for that component type.

Please note: Whilst attempts have been made to align the benchmarking of both methodologies described above, they do determine performance in different ways. The number of BREEAM credits awarded by each method may therefore differ for the same water component specification. It is important to be aware of this difference when applying BREEAM New Construction to a number of different building types that form a part of the same overall development.

Other information

Certification of Water Efficient Products

Product certification schemes provide specifiers and clients with greater assurance of manufacturers’ claims regarding the water efficiency performance of their products and therefore the potential water savings of different products. Specifying water efficient fittings certified by accredited bodies are encouraged by BREEAM, but at present the scheme does not require components to meet an approved standard to gain BREEAM credits.

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