As the Government’s plan to ‘remove red tape and get more houses built’ brings us ever closer to a return of the appalling build quality of housing in the 1970s, at least one positive thing may come out of the recent Housing Standards Review. The UK may be about to have a water fittings standard that housebuilders can use to show compliance with the requirement for water efficiency. If it does happen it will be a major coup for those who have been arguing for such a standard for many years – the AECB and the EST being the prime movers in this respect.

A fittings standard brings clarity to the flow rates and fill volumes of the appliances installed compared to the water calculator (the current way to show compliance with the Building Regulations), which is based on a random set of use factors to give a notional litres/person/day usage. Up to March 2013, over 90,000 dwellings have been built to Code Level 3 and almost 18,000 to Code Level 41. But it is impossible from the headline figures to know what appliances have been fitted into those dwellings. We can make educated guesses (for example, 4/2.6 dual flush WCs in homes for private sale to allow for the highest possible flow rate at showers, and 6/4 litre dual flush WCs and correspondingly lower shower flow rates in social housing) but guesses are not facts2. If the same dwellings had been built to meet a fittings standard (whether national base level or additional local level), maximum flow rates and flush/fill volumes could be stated with absolute confidence.

The AECB Water Standards were used as the blueprint for the proposed water fittings standard. However, to be acceptable to the many voices around the table at the Water Efficiency Review Board who consider any shower less than 12 litres/minute equates to a dribble of water and a denial of a basic human right, shower flow rates were set higher than the AECB standard. Two levels were set – a “national base level” and an “additional local level”.

National Base Level – proposed
Water Fitting Flow rate or Volume Water Label Rating
WC 6/4 litres dual flush or
4.5 litres single flush
Light green
Shower 10 litres/minute Light green
Bath 185 litres Yellow
Basin Taps 6 litres/minute Dark green
Sink taps 8 litres/minute Light green


Additional Local Level – proposed
Water Fitting Flow rate or Volume Water Label Rating
WC 4/2.6 litres dual flush Dark green
Shower 8 litres/minute Light green
Bath 170 litres Light green
Basin Taps 5 litres/minute Dark green
Sink taps 6 litres/minute Dark green

The performance specification, especially for the additional local level of the fittings standard, was chosen with careful attention to what is currently being installed in new homes (i.e. appliances that developers are already fitting with confidence), what is available on the UK market and how efficient the appliance is (as rated by the Water Label). One of the arguments that has always been wheeled out against a water fittings standard is the lack of choice for consumers. As if we are living in the Soviet Union in the 1960’s and there is only one 6/4 litre dual flush WC out there, or just one choice of bath at 185 litres. In reality there are myriads of options up to and including the maximum flow rate or flush/fill volume. The standard also ensures that the performance of the fitting will satisfy the householder. Going too low risks dissatisfaction from users about flow rates or bath volumes and is counterproductive.

Large developers are commonly installing 4/2.6 dual flush WCs to meet Level 3 of the Code for Sustainable Homes, (because if they do the water calculator allows them to install showers with a flow rate of 12 litres/minute.) A shower with a flow rate of 8 litres/minute is twice as high as the best performing electric shower, and is as high as the flow rate in many hotels now (even 4 star hotels). A bath with a volume of 170 litres is the standard both length of 1700 mm, (allowing users to lie comfortably for relaxation purposes) and is the standard depth of 400mm from the top to base of bath (ensuring that baths are easy to get out of and to lower oneself into, meeting the required standard for lifetime homes). A flow rate of six litres a minute from kitchen sinks will ensure fast fill of kettles and saucepans, (5 to 10 seconds) fast fill of bowls (20-30 seconds) and relatively fast fill of buckets (45-60 seconds).

So, a robust set of standards to go out to public consultation, with the expectation that whilst the national base level was relatively lax, the higher standard was likely to be required by local councils in both moderately and severely water stressed areas. So far so good until, eight months after the review process, when the proposal for public consultation came out with two key changes. First the statement that: “The requirement for a higher water efficiency standard within a local plan will only be able to be made after consultation with the local water supplier, developers and the Environment Agency and is consistent with a wider approach to water efficiency as set out in the local water undertaker’s water resources management plan”. And secondly, a question about whether flow rates and volumes had been set too low.

The results of the consultation are not in as I write but my concern is that even if a fittings standard is agreed it will have been watered down so much it will not have a meaningful effect on water efficiency. And any additional local level is unlikely to be implemented due to the cost of the consultation required, the fact that water suppliers make money by selling water and that developers are currently installing showers at 12 litres/minute and argue they cannot sell homes if the flow rate is lower. In the rush to get more homes built, it seems the developers are still calling the shots and water efficient new homes will still be far from the norm.



  1. Code for Sustainable Homes and SAP ratings statistical release May 2013. Issued by the DCLG
  2. And if a RWH system has been installed, then all educated guesses about flow rates, bath/WC cistern volumes are off.


Published in Green Building Magazine, Winter 2013

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Finally – a water fittings standard for the UK?