Britain is gradually waking up to how wasteful it has been as a nation with its precious water resources. Some parts of the country have already experienced alarming shortages and a hosepipe ban is never far away particularly in the over-populated South East. - Regulators have tiled to address this issue through the new version of Building Regulations Part G (sanitation, hot water safety and water efficiency) and have set about trying to enshrine a whole new water saving and safety culture in law.
At the recent World Plumbing Conference in Edinburgh, an experienced plumber from Australia expressed amazement at what we have been allowed to get away with over there. Earl Setches, from the Australian Plumbing Trades Employees’ Union, told the conference that nothing gets built over there without rainwater harvesting as standard—and the water used in their buildings is recycled twice or three times at least.
Australia is a hot, dry place and their water culture is very different to ours. However, things are changing here too and legislators have been moved to bring in measures consistent with a country that can no longer guarantee plentiful supplies of clean water.
In the frontline
Saving and recycling water is as much about education and the behaviour of consumers, but our industry cannot afford to duck the engineering challenge. A family of four can use 220,000 litres of hot water a year, which takes l2OkWh to heat — easily the biggest energy usage in the home — which is why that aspect has been addressed in Part L. Each of us also uses between 150 and 200 litres of ‘potable’ water a day,’ and the new Part C sets about bringing that down to 125 litres. As time moves on plumbing and heating engineers are likely to find themselves, more and more, in the frontline on water conservation
Part G requires plumbing and heating engineers to apply the ‘Water Efficiency Calculator’ to all new water’ trying installations. This includes target flow rates for appliances, including gushing toilets, showers arid baths, and is designed to increase the number of ‘low flow’ units installed.
Average flow rates from standard showers is estimated to be around 12 litres per minute - so it doesn’t make a math’s genius to work out that ‘average’ stilt no longer be good enough. Low flow or aerated shower heads will be the order of the day. The Water Efficiency Calculator can be viewed online by visiting: www.planningportal.gov.uk/uploads/br/water_efficiency_calculator.pdf
It explains how to ensure the system you install will keep water consumption under 125 litres per person per day — and it is not easy. The new limit applies to both new-builds and extensions with the requirement that the person carrying out the work must give the local Building Control Officer (BCO) a notice ‘specifying the potential consumption of wholesome water per person per day’ within five days of completion. The BCO will not certify the work until they have received this report.
Reduced Flow
The biggest problem will be consumer reaction. British homeowners have started to expect ‘monsoon’ type showers as their right — particularly as we were deprived of such things for decades. Just as soon as they started to be widely available, the UK legislates them out of existence! Time will tell on that one.
An anomaly, which was also pointed out at the World Plumbing Conference, was that the popular environmental assessment method BREEAM does not give proportionate weight to water conservation. Only 2.5% of the rating points available are awarded for that aspect of a building’s design compared with 33% for energy efficiency. That balance will, surely, change.
Safety steps
Apart from the water conservation aspects, legislators have also beefed up safety requirements The 03 section tackles the serious problem of scalding by requiring the fitting of thermostatic taps that limit the water temperature to 48°C for all baths. Strong representation was made to legislators for extending this requirement - to basins, but because these account for far fewer accidents— 93% of scaldings take place in the bath this wasn’t deemed necessary
More safety measures are also being applied to water storage systems, including domestic hot water cylinders and the thermal stores used in renewable systems. The rules that previously only applied to unvented systems, such as the use of pressure valves and temperature control, are being extended despite opposition front some manufacturers.
The regulations state: ‘Any hot Water system, including associated storage or expansion vessel, shall resist the effects of any temperature or pressure that may occur in normal rise or as a consequence of a reasonably anticipated malfunction.
‘Any pair of a hot water system that incorporates a hot water storage vessel shall incorporate precautions to ensure that the temperature of the stored water does not exceed 100°C and that any discharge from safety devices is safely conveyed to a point where it is both visible and will not cause a danger to persons in or about the building’.
Hygiene issues
Water hygiene standards have also been stepped up is Port 01, which covers cold water supplies, particularly in relation to areas where food is prepared.
G1 is a new requirement stating that a supply of wholesome water must be provided for the purposes of drinking, washing or food preparation,’ the legislation says. ‘Thus wholesome water must be provided where drinking water is drawn off, to any washbasin, bidet, fixed bath and shower in a bathroom and to any sink in any area where food is prepared’. It also calls for ‘water of a suitable quality to arty sanitary convenience fitted with a flushing device’.
It is the use of the word ‘wholesome’ that is the key. This is defined as water complying with requirements of the ‘standards of wholesomeness’ established in the Water
industry Act 1991. It separates the use of wholesome water from greywater and harvested rainwater that does not meet the definition of wholesome, but can be used for certain applications, such as watering plants.
There were transitional provisions in place to allow time to adapt to these new rules. Projects that had started prior to the date the new provisions came into force —6 April 2010 were exempt, but we are now a good year on from when those provisions lapsed. We must all now comply with the new requirements and, in truth, there is not too much to argue with.
Good legislation tends to support common sense and there is much in Part C that simply backs up good, sensible engineering and behaviour. Surely anything that reduces water waste and scalding incidents must be a good thing? Or is life ever that simple?
