Tradespeople who have been working for more than ten years in their industry are the most likely to complete projects without getting paid for them, according to new research.

A Direct Line for Business survey has revealed that almost three quarters of tradespeople work unpaid overtime every week, totalling 5.29 hours in seven days and 275 hours a year.

Whether it is installing an electrical consumer unit in a customer's home or repairing a broken down boiler, the report found one in ten of Britain's 2.8 million tradespeople work an extra ten hours or more a week without pay, adding up to 520 hours a year. This means they could be losing thousands of pounds in income.

Jazz Gakhal, head of Direct Line for Business, commented: "Tradespeople are the unsung heroes leading the way in nursing our economy back to health.

"The research shows that, despite the sometimes negative publicity that surrounds the work ethic of tradespeople, they are doing more than their fair share and setting the right example for the rest of the UK's workforce."

She added that the next time householders see their builder or plumber take a tea break, they should be conscious that they are probably getting free hours spent working on their home improvements.

However, help may be at hand for tradespeople looking to cut down on their unpaid hours with the recently launched Meteor Electrical iPhone app, which can speed up the time taken to browse and order various products.

Plumbers who download the app will be able to scroll through more than 7,000 parts, price them up and order them at the touch of a button while they are on the job. Tradespeople can also store products to buy later after calculating a quote for the homeowner.

The app is compatible with iPhone, iPod Touch and iPad devices and requires iOS 3.0 or a later version to run.