Showers are the biggest consumers of water in the home, using a quarter of the total.

The average shower lasts seven-and-a half minutes – with one in eight taking more than ten minutes.

On average, Britons shower 4.4 times a week, and take 1.3 baths. Those in larger households with more people take fewer showers each week, but stay in longer when the opportunity arises, the study found.

The EST report is the largest and most comprehensive study of water use ever presenting findings from a study of 86,000 British households.

Away from the bathroom, the report, revealed that just over a fifth (22 per cent) of household water is used in the kitchen, with washing machines, dishwashers, kettles and taps all taking their share.

More than nine in ten people (95 per cent) boil the kettle every day, with 40 per cent doing so five times a day or more.

However, three quarters of households still boil more water than they need – with overfilling costing Brits £68m a year.

Despite the increasing use of new technology in UK homes, dishwashers are still second-best to handwashing in many cases.

The average British household washes dishes by hand ten times a week, but only uses the dishwasher three times a week. Energy Saving Trust said that larger households could actually make greater energy and water savings by using an efficient, modern dishwasher rather than washing by hand.

Andrew Tucker, water strategy manager at Energy Saving Trust, said: “When people think of energy use they think of heating and lighting, running electrical appliances or filling the car with petrol. It’s all too easy to turn on the tap and not think about the consequences.

“But there is an environmental and energy cost attached to water which many people do not consider. On average, hot water use contributes £228 to the average annual combined energy bill.

“It’s clear that we are all using more water-consuming appliances regularly, especially showers, but that doesn’t mean we’re powerless to control our water use.

“By reducing the amount of water – especially hot water – that we use, we can cut down on the energy demands of our lifestyles, which have changed radically over the last 50 years.”

Three easy ways to cut your energy bills by £22 a year:

• Showering smarter – installing an eco-shower head to a mixer or power shower – Water Energy Calculator results suggest could that 49 per cent of households may be eligible to do this;

• Turning it down – washing clothes at 30C – saving 40 per cent on a wash at 50-60C;

• Budgeting your brews – boil only the water you need when you fill the kettle – overfilling costs Brits £68 million a year.