(Building Research Establishment Environmental Assessment Methodology)

This is the leading and most widely used environmental assessment method for buildings.

It is the set standard for best practice in sustainable design and has become the ‘DeFacto’ measure used to describe a buildings environmental performance.
BREEAM assesses buildings against a set criteria and provides an overall score which will fall within a band providing either a Pass, Good , Very Good, Excellent or Outstanding rating.

Water usage is a part of the assessment and water efficiency levels are achieved by improving water usage from a set baseline.
The attached sheet shows table 8-1 which shows the baseline for water usage dependant on the component type as set by BREEAM, and the reductions required in order to meet the various levels.

In the continued work by VOLA on sustainability and environmental concerns.
Part of this process has been to produce a range of flow restricting aerators and flow restrictors.
The many different valve and restrictor options offered by VOLA enable the specifier to select the combination most suitable for the purpose, and making it far easier to meet the requirements for the desired BREEAM level.


Checklists and Tables
Table - 18 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 and therefore reflect robust levels of typical, good, best and exemplary practice.

Table - 18: 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
(2 or more urinals)
7.50 6 3 1.50 0.75 0 litres/bowl/hour
(1 urinal only)
10 8 4 2 1 0 litres/bowl/hour
rainwater system
0 0 0 0,25 0,5 0,75 % 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
dish washers
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
8 7 6 5 4 3 litres/rack
Industrial sized wash- ing machines
14 12 10 750 5 450 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.