This was originally published in CAT's Membership magazine, Clean Slate.
Saving water helps protect aquatic environments, reduces greenhouse gas emissions and can save you money. Common sense suggests that taking a shower uses less water than a bath, but this is not always so. Although most electric showers will use less than a bath, a modern 'power shower' can use quite a bit more. To help reduce flows on pumped and mains-pressure shower systems, a number of manufacturers are producing 'water saving' shower heads. This seems like a good idea in theory, but how do they shape up in practice, how much water do they actually save, and do they offer value for money?
We tested five shower heads with a five-minute shower at mains pressure (at approximately 2 bar) from a combi boiler, measuring water flow and assessing user comfort. The shower with the highest flow rate of 9.9 litres per minute was the supposedly water-saving 'Flowpoint HH336', followed closely by the standard shower head (9.5 litres per minute) and the other Flowpoint unit (9.4 litres per minute). All three gave a vigorous and very comfortable shower, but none could really be termed water-saving.
The other two arrangements did offer significant water savings. The Oxygenics shower head came next in the league table with an average flow of 6.1 litres per minute. Now that is a saving. A leisurely seven-minute shower would use less than half the water of even a modest bath. As to comfort, this aerating shower head was less forceful than the three above but nonetheless gave a pleasant shower with a mildly vigorous feel. On the downside, it was noticeably noisy and a little reminiscent of a distant jet engine...
The most water-efficient option tested was the standard shower fitted with an 'Aquaflow' regulator (http://www.aquaflowregulators.co.uk/index.html), giving a flow of 5 litres per minute. This gave a similar level of showering comfort to the oxygenics head, with good water coverage, but was a slightly softer experience with no feeling of vigour to the jets. It was less noisy and considerably cheaper.
So, which showerhead to choose? Given that there is very little difference between the standard and 'Flowpoint' shower heads on mains-pressure systems (like a combi boiler) you might as well stick with what you already have and save yourself the £20.
Only the Oxygenics head or the Aquaflow insert offered any real water savings. At £40 the Oxygenics is relatively expensive, bearing in mind you can get similar results at a fraction of the cost using a flow regulator. Nonetheless, if you want a water-efficient 'luxury' bathroom you will have to spend if you wish to be 'invigorated' by your shower. If you're not after eco-chic but just saving water then it needn't be expensive. Try a 6 litre per minute regulator for substantial water savings, and if you find this not to give enough flow for your taste then you could upgrade to 7 litres or more, as desired.
Oxygenics - £40 - 6.1 litres/minute
Flowpoint HH336 - £20 - 9.9 litres/minute
Flowpoint HH412 - £20 - 9.4 litres/minute
Conventional thermostatic mixer - £0 (came with shower) - 9.5 litres/minute
Conventional plus Aquaflow regulator - £2.50 - 5.0 litres/minute
The Aquaflow range of flow regulators should be available (perhaps only to order) through many plumbers' merchants (e.g. Wolseley, Graham, Plumb Center).