Market Transformation Programme: BNWAT28 Water Consumption in New and Existing Homes (2008)
This Briefing Note provides details of the key findings from a recent water industry collaborative research project conducted by WRc Plc into the water consumption of microcomponents in new properties1. The Market Transformation Programme (MTP) has access to limited outputs from the research, including the summary statistics, but not the full database of information.
It is projected that there will be 3 million new homes built in the UK by 2020. Understanding water use in new dwellings is a key factor in forecasting domestic water use, quantifying the impact of water efficiency measures and estimating the impact of new policy initiatives. These initiatives include the Code for Sustainable Homes and the proposed revision to the Building Regulations to include a whole-of- house water efficiency requirement. Some concern has been expressed that predicted water efficiency savings may not be realised in practice owing to uncertainties in evidence relating to actual water use, consumer behaviour, and product performance (new and retrofit) in new homes.
The project conducted by WRc aimed to collect data on the microcomponents of water use in new dwellings to better understand how water use in new dwellings differs from that in older, unmeasured properties. Measuring the microcomponents of water use allows us to break down domestic water consumption into individual components (WC use, bathing, showering, tap use, outside use, washing machine use, dishwasher use etc) expressed in terms of ownership, volume per use and frequency of use.
2.1 The Identiflow® system
The domestic consumption of water consists of a number of ‘microcomponents’. Typically, these differentiate the use of appliances such as washing machines or dishwashers, personal washing by bath or shower, toilet use, and the use of internal or external taps. Measurement of these microcomponents provides reliable information on the way in which domestic consumers use water in the home. The Identiflow®2 technique used to collect data for this project involves measurement of household water use at the flow meter supplying the house and is a means of categorising its constituent microcomponents from these measurements.
2.2 The Identiflow® sample structure
The property sample structure for the project was designed around three key criteria:
- Ability to compare results with a dataset of microcomponent information on older, unmeasured properties
- Trends in house building
- Consideration of all major influences on demand.