Inappropriate clothes will cost UK firms millions of pounds a year in higher energy bills this winter, as staff refuse to put away their summer wardrobes, instead turning up the heating so they can continue to sit at their desks in t-shirts and vest tops.

That is the conclusion of new research from energy giant E.ON which found that almost a fifth of UK workers have control over their office thermostat, meaning that not only are arguments over office temperatures commonplace, but also that businesses often face higher energy bills as t-shirt clad staff turn up the heating during the winter.

Jane Lomas, workplace improvement manager at E.ON, said that while most offices aimed for an ideal office temperature of around 19°C to 20°C, "growing personal choice in office dress can lead to people making seasonally inappropriate choices".

A spokesman for the company added that the aim of the research was to try and encourage people to "dress more appropriately in the office", adding that dressing in line with the seasonal climate "can make a big difference to energy use in the office".

Research from The Carbon Trust has shown that turning down the thermostat by just one degree centigrade can cut heating bills by eight per cent, while also delivering significant carbon savings.

However, the survey of 2,000 people found that regardless of how people are dressed, arguments over how warm the office should be means many offices are often hotter than they need to be.

The research found that disputes over office temperature frequently opened up another front in the battle of the sexes with majority of women, unhappy about the temperature in their workplace, feeling cold, while men were twice as likely to ask for the heating to be turned down.

E.ON said that the best way to address differing degrees of tolerance to temperature while helping to ensure heating bills and energy use are kept at a reasonable level is to make a dedicated individual responsible for office heating and cooling.

The company is running a campaign to recruit 10,000 so-called energy marshalls nationwide to fill such a position and also help promote energy efficiency measures in the workplace.

"If there is a problem solving the different request for temperature change, then having an energy marshall in place can help you reach a happy medium," said the company spokesman.