…but consumer approach to water usage needs to change
Homes built to modern sustainability standards are having a positive effect on household water consumption, according to a new study by the NHBC Foundation.
The report, Water consumption in sustainable new homes, monitored seven homes built to Code for Sustainable Homes or EcoHomes standards to measure actual water use for a period of between 6 and 12 months. The report reveals that average water consumption in these homes was 12% under the water use targets of 125 litres per person / day now set out in Part G of the building regulations.
The report also identifies that occupant behaviour has a significant impact on the amount of water used in the home, but the installation of water efficient fittings and appliances has only a limited effect and suggests attitudes to water consumption need to be addressed.
Key findings from the report highlighted:
- Average water consumption measured in the homes was less than the current average in existing UK homes (150 litres per person/day) and less than the target set in the building regulations Part G (125 litres per person/day)
- The water calculator used by the Code and Part G does not accurately predict water consumption, generally significantly under-estimating consumption
- In at least one case, occupants were found to be avoiding the use of low-flow kitchen sink taps by filling kettles and other kitchen utensils from bath taps
- On average, hot water accounted for 32% of the total water consumption
- Generally for every pound spent on water use, including water bill and energy bill for hot water, approximately 2kg of CO2 was emitted
- The greatest potential water savings is likely to be achieved by reducing the amount of water used in WCs, baths and showers.
Neil Smith, Research Manager at NHBC Foundation explains: “This report provides useful data on the actual use of water in homes and shows that, although consumption is being reduced, the calculator used by the Code and Part G is not able to predict domestic water use accurately.
“Reducing water consumption is not just about installing water efficient fittings; it requires changes to consumer behaviour. If the technology is inconvenient, consumers will find ways of getting around it, for example, using the bath taps to fill up a kettle rather than using the low-flow tap in the kitchen.”
Neil Smith added: “Water metering encourages households to reduce their consumption, and is standard for new homes. Wide scale implementation of water metering in the existing housing stock would help to both reduce national consumption substantially and create a financial incentive for all households to use less water.”
The Government is currently understood to be considering the options for making water metering mandatory for all homes, which has the potential to have a far greater effect on reducing national water consumption.
The report is available for download at www.nhbcfoundation.org